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Industrial reference

Singer 321C-134M-04

43 cited answers2 documentsCoverage limits

Needles, bobbins, feet and other details for this model. Check the requirements before choosing parts.

Before choosing a part

Compatibility essentials

Start with these documented details. Read the requirements with each answer before choosing a needle, bobbin or foot.

Needle system / designation

Use Singer needle6120-06; exact model size is separately shown in specification/gauge rows.

Requirements and sources →
Needle sizes by fabric and use

Not yet confirmed here: Manufacturer accessory group, Presser-foot shank type, Foot attachment, Foot holder / mount, Foot interface / generation, Bobbin type / class, Bobbin material, Bobbin diameter, Bobbin height, Hook type, Maximum stitch / zigzag width, Feed system, Bobbin loading direction. What is still to confirm →

Model & names

Model
Singer 321C-134M-04

Other names, regional versions and related models have not been confirmed here. A shared manual, product line or accessory group does not identify the machine's family.

What do you need help with?

Full-manual access: this profile supplies document references and page locators, not the complete manual or its diagrams. No matching publisher file is linked here. Obtain the exact manual and read the full procedure, figures and safety precautions before following an operating or service answer. Check document access and scope →

What must be isolated, guarded or handled by trained personnel?

Before you use this answer

Read the exact model/table-column conditions, full source diagram and safety prerequisites before any procedure. Trained-service limits remain attached. Literal parts and sizes do not establish substitutes, adapters, retail fitment or installed electrical configuration. The Portuguese edition establishes document presence only.

Documents and page references →

Which exact model-column stitch, thread, needle, width and speed specifications are documented?

Before you use this answer

Read the exact model/table-column conditions, full source diagram and safety prerequisites before any procedure. Trained-service limits remain attached. Literal parts and sizes do not establish substitutes, adapters, retail fitment or installed electrical configuration. The Portuguese edition establishes document presence only.

Documents and page references →

Which clutch-drive and frequency-dependent pulley references are documented?

Before you use this answer

Read the exact model/table-column conditions, full source diagram and safety prerequisites before any procedure. Trained-service limits remain attached. Literal parts and sizes do not establish substitutes, adapters, retail fitment or installed electrical configuration. The Portuguese edition establishes document presence only.

Documents and page references →

Where are the head-support, belt, rotation and pedal setup references?

Before you use this answer

Read the exact model/table-column conditions, full source diagram and safety prerequisites before any procedure. Trained-service limits remain attached. Literal parts and sizes do not establish substitutes, adapters, retail fitment or installed electrical configuration. The Portuguese edition establishes document presence only.

Documents and page references →

How does the source document needle insertion and its safety prerequisites?

Before you use this answer

Read the exact model/table-column conditions, full source diagram and safety prerequisites before any procedure. Trained-service limits remain attached. Literal parts and sizes do not establish substitutes, adapters, retail fitment or installed electrical configuration. The Portuguese edition establishes document presence only.

Documents and page references →

Which original threading diagram and route should I consult?

Before you use this answer

Read the exact model/table-column conditions, full source diagram and safety prerequisites before any procedure. Trained-service limits remain attached. Literal parts and sizes do not establish substitutes, adapters, retail fitment or installed electrical configuration. The Portuguese edition establishes document presence only.

Documents and page references →
More questions (16)

What precautions and oiling references apply before first use or return after disuse?

Before you use this answer

Read the exact model/table-column conditions, full source diagram and safety prerequisites before any procedure. Trained-service limits remain attached. Literal parts and sizes do not establish substitutes, adapters, retail fitment or installed electrical configuration. The Portuguese edition establishes document presence only.

Documents and page references →

Which literal needle catalog number, model size and gauge occurrences are printed?

Before you use this answer

Read the exact model/table-column conditions, full source diagram and safety prerequisites before any procedure. Trained-service limits remain attached. Literal parts and sizes do not establish substitutes, adapters, retail fitment or installed electrical configuration. The Portuguese edition establishes document presence only.

Documents and page references →

Which thread-tension controls and operating qualifications are documented?

Before you use this answer

Read the exact model/table-column conditions, full source diagram and safety prerequisites before any procedure. Trained-service limits remain attached. Literal parts and sizes do not establish substitutes, adapters, retail fitment or installed electrical configuration. The Portuguese edition establishes document presence only.

Documents and page references →

Which stitch-type and looper-guide conditions must remain together?

Before you use this answer

Read the exact model/table-column conditions, full source diagram and safety prerequisites before any procedure. Trained-service limits remain attached. Literal parts and sizes do not establish substitutes, adapters, retail fitment or installed electrical configuration. The Portuguese edition establishes document presence only.

Documents and page references →

What differential-feed adjustment reference and effects are documented?

Before you use this answer

Read the exact model/table-column conditions, full source diagram and safety prerequisites before any procedure. Trained-service limits remain attached. Literal parts and sizes do not establish substitutes, adapters, retail fitment or installed electrical configuration. The Portuguese edition establishes document presence only.

Documents and page references →

Where is the source stitch-length control reference?

Before you use this answer

Read the exact model/table-column conditions, full source diagram and safety prerequisites before any procedure. Trained-service limits remain attached. Literal parts and sizes do not establish substitutes, adapters, retail fitment or installed electrical configuration. The Portuguese edition establishes document presence only.

Documents and page references →

Which foot assembly identifiers, service limits and lift are documented?

Before you use this answer

Read the exact model/table-column conditions, full source diagram and safety prerequisites before any procedure. Trained-service limits remain attached. Literal parts and sizes do not establish substitutes, adapters, retail fitment or installed electrical configuration. The Portuguese edition establishes document presence only.

Documents and page references →

Which original knife, filter, gauge, needle-clamp and looper-row items are listed?

Before you use this answer

Read the exact model/table-column conditions, full source diagram and safety prerequisites before any procedure. Trained-service limits remain attached. Literal parts and sizes do not establish substitutes, adapters, retail fitment or installed electrical configuration. The Portuguese edition establishes document presence only.

Documents and page references →

What reservoir, oil-change and filter-care references are documented?

Before you use this answer

Read the exact model/table-column conditions, full source diagram and safety prerequisites before any procedure. Trained-service limits remain attached. Literal parts and sizes do not establish substitutes, adapters, retail fitment or installed electrical configuration. The Portuguese edition establishes document presence only.

Documents and page references →

What cleaning reference and solvent restriction are documented?

Before you use this answer

Read the exact model/table-column conditions, full source diagram and safety prerequisites before any procedure. Trained-service limits remain attached. Literal parts and sizes do not establish substitutes, adapters, retail fitment or installed electrical configuration. The Portuguese edition establishes document presence only.

Documents and page references →

Which safety-device, fixing, belt and electrical-condition checks are documented?

Before you use this answer

Read the exact model/table-column conditions, full source diagram and safety prerequisites before any procedure. Trained-service limits remain attached. Literal parts and sizes do not establish substitutes, adapters, retail fitment or installed electrical configuration. The Portuguese edition establishes document presence only.

Documents and page references →

Which initial running-in speed and oil-change conditions apply to a new machine?

Before you use this answer

Read the exact model/table-column conditions, full source diagram and safety prerequisites before any procedure. Trained-service limits remain attached. Literal parts and sizes do not establish substitutes, adapters, retail fitment or installed electrical configuration. The Portuguese edition establishes document presence only.

Documents and page references →

Where are the original possible causes of needle breakage?

Before you use this answer

Read the exact model/table-column conditions, full source diagram and safety prerequisites before any procedure. Trained-service limits remain attached. Literal parts and sizes do not establish substitutes, adapters, retail fitment or installed electrical configuration. The Portuguese edition establishes document presence only.

Documents and page references →

Where are the original possible causes of thread breakage and skipped stitches?

Before you use this answer

Read the exact model/table-column conditions, full source diagram and safety prerequisites before any procedure. Trained-service limits remain attached. Literal parts and sizes do not establish substitutes, adapters, retail fitment or installed electrical configuration. The Portuguese edition establishes document presence only.

Documents and page references →

Where are the original possible causes of uneven stitches and puckering?

Before you use this answer

Read the exact model/table-column conditions, full source diagram and safety prerequisites before any procedure. Trained-service limits remain attached. Literal parts and sizes do not establish substitutes, adapters, retail fitment or installed electrical configuration. The Portuguese edition establishes document presence only.

Documents and page references →

Which English instruction/parts original is retained, and which Portuguese edition is presence-only?

Before you use this answer

Read the exact model/table-column conditions, full source diagram and safety prerequisites before any procedure. Trained-service limits remain attached. Literal parts and sizes do not establish substitutes, adapters, retail fitment or installed electrical configuration. The Portuguese edition establishes document presence only.

Documents and page references →

Manuals, parts books & more

Manuals & manufacturer documents

Available documents & sources

Operating manual
Singer321C High Speed Overlock Machine — Instruction Manual and Parts List · P/N364336-001 Rev3 May2012
Singer321C Máquina Overloque de Alta Velocidade — Manual de Instruções e Lista de Peças · P/N364336-003 Rev1 September2011
Parts references cited within operating manuals
Singer321C High Speed Overlock Machine — Instruction Manual and Parts List · P/N364336-001 Rev3 May2012

Cited parts content in an already-listed manual; this is not an additional standalone document.

Publisher links below distinguish a matched file from a listing.

Choose the document for your task: an instruction manual, service manual, parts list and accessory guide answer different questions.

About this document & page references →

Instruction manual

Singer321C High Speed Overlock Machine — Instruction Manual and Parts List

Singer59 pagesEnglish
Edition and models

Edition: P/N364336-001 Rev3 May2012

Models referenced here: Singer 321C-134M-04

Cited retained OEM manual and parts list: Page references identify this exact retained English edition. A matching current public download has not been established for these references. The original is retained privately and is not hosted by SewIndex.

About this document & page references →

Instruction manual

Singer321C Máquina Overloque de Alta Velocidade — Manual de Instruções e Lista de Peças

Singer58 pagesPortuguese
Edition and models

Edition: P/N364336-003 Rev1 September2011

Models referenced here: Singer 321C-134M-04

Retained OEM edition: Recorded for document presence and literal edition only. Technical answers use the English instruction manual; these editions are not interchangeable translations. Direct model association for translated technical use has not been established. A matching public download has not been established. The original is retained privately and is not hosted by SewIndex.

Needle, bobbin & presser-foot details

Read the model-specific requirements with each answer before choosing parts.

Needle

Required catalog

  • Exact 321C-134M-04, plain clutch-motor column, English May 2012 original only; no E/direct-drive, 321D/K, sibling/region or 2011 inheritance.; Literal OEM needle catalogue, not inferred DB/DC/system equivalence or other brand permission.

Use Singer needle6120-06; exact model size is separately shown in specification/gauge rows.

Sources and pages

Needle insertion

  • Exact 321C-134M-04, plain clutch-motor column, English May 2012 original only; no E/direct-drive, 321D/K, sibling/region or 2011 inheritance.; Power isolated; complete figure 7 required. Do not substitute another model groove/scarf description.

Insert the needle fully with slot toward the back and tighten screw1.

Sources and pages

Exact source size

  • Exact 321C-134M-04, plain clutch-motor column, English May 2012 original only; no E/direct-drive, 321D/K, sibling/region or 2011 inheritance.; Exact original row/group geometry; specification/reference only, no alternate attachment clearance, substitute needle or unrestricted material inference.

6120-06 75/11

Sources and pages

Alternate systems and special needles

Not yet verified
  • Not yet verified: Alternate standardized systems/products/points/materials/twin/special-use conditions are not established beyond literal6120-06 and exact source size.

Source gauge occurrences

  • Exact 321C-134M-04, plain clutch-motor column in English May 2012; independent needle/bobbin/foot axes and unknown fit ceilings preserved.; Preserve separate source occurrences; single-needle dash and 0 are not normalized into a universal geometry or attachment-compatibility rule.

Specification gauge prints dash; gauge-parts row prints0.

Sources and pages

Bobbin

System case dimensions substitutions

Not yet verified
  • Not yet verified: No accepted exact bobbin system/case/dimensions/material/substitutions evidence. Generic safety mentions of bobbin/shuttle do not establish this overlock model has that mechanism; unknown is not incompatible.

Presser foot

Source assembly and service boundary

  • Exact 321C-134M-04, plain clutch-motor column, English May 2012 original only; no E/direct-drive, 321D/K, sibling/region or 2011 inheritance.; Use exact gauge-row complete foot separately; no standard mount/shank/holder/adapter or retail fit inferred.

Source parts distinguish foot arm20101027 and shaft20102020; generic complete foot is placeholderxxxxxxxx, not a purchasable part.

Sources and pages

Source lift mm

  • Exact 321C-134M-04, plain clutch-motor column, English May 2012 original only; no E/direct-drive, 321D/K, sibling/region or 2011 inheritance.; Exact original row/group geometry; specification/reference only, no alternate attachment clearance, substitute needle or unrestricted material inference.

5.5

Sources and pages

Mount shank adapters retail fit

Not yet verified
  • Not yet verified: Standardized mount/shank/presser-bar interface, holder/adapters and retail product fit are not established by lift or original complete-foot numbers.

Specifications & documented facts

Specifications apply to the named model and document edition. Read any setup, fabric or safety requirements with the answer.

Documented overlock specifications

Open each full answer for its exact model, table-column conditions and page references. Overlock stitch width does not establish maximum zigzag width or attachment compatibility.

Performance & stitch capabilities

Machine type

  • Exact 321C-134M-04, plain clutch-motor column, English May 2012 original only; no E/direct-drive, 321D/K, sibling/region or 2011 inheritance.; Exact model table controls thread count, application and limits; no unrestricted material capability.

High-speed industrial overlock machine.

Sources and pages

Source stitch length mm

  • Exact 321C-134M-04, plain clutch-motor column, English May 2012 original only; no E/direct-drive, 321D/K, sibling/region or 2011 inheritance.; Merged model-group specification verified in original geometry; not every differential-table wheel setting or alternate variant maximum.

3.6

Sources and pages

Source differential ratio

  • Exact 321C-134M-04, plain clutch-motor column, English May 2012 original only; no E/direct-drive, 321D/K, sibling/region or 2011 inheritance.; Exact selected model-group specification; other adjustment-table machine types or 1:3/1:4 settings do not expand this model range.

0.7–2.0

Sources and pages

Source needle count

  • Exact 321C-134M-04, plain clutch-motor column, English May 2012 original only; no E/direct-drive, 321D/K, sibling/region or 2011 inheritance.; Exact original row/group geometry; specification/reference only, no alternate attachment clearance, substitute needle or unrestricted material inference.

1

Sources and pages

Source thread count

  • Exact 321C-134M-04, plain clutch-motor column, English May 2012 original only; no E/direct-drive, 321D/K, sibling/region or 2011 inheritance.; Exact original row/group geometry; specification/reference only, no alternate attachment clearance, substitute needle or unrestricted material inference.

3

Sources and pages

Stitch width mm

  • Exact 321C-134M-04, plain clutch-motor column, English May 2012 original only; no E/direct-drive, 321D/K, sibling/region or 2011 inheritance.; Exact original row/group geometry; specification/reference only, no alternate attachment clearance, substitute needle or unrestricted material inference.

4.0

Sources and pages

Maximum speed spm

  • Exact 321C-134M-04, plain clutch-motor column, English May 2012 original only; no E/direct-drive, 321D/K, sibling/region or 2011 inheritance.; Exact original row/group geometry; specification/reference only, no alternate attachment clearance, substitute needle or unrestricted material inference.; New machine runs at 80 percent maximum speed during the first four weeks; after that initial cycle change oil before full specified speed. Guards/lubrication/trained operator and material/thread conditions also govern.

6000

Sources and pages

Source application

  • Exact 321C-134M-04, plain clutch-motor column, English May 2012 original only; no E/direct-drive, 321D/K, sibling/region or 2011 inheritance.; Exact original row/group geometry; specification/reference only, no alternate attachment clearance, substitute needle or unrestricted material inference.

Three-thread back latch overlock

Sources and pages

Parts

Oil filter and lower knife

  • Exact 321C-134M-04, plain clutch-motor column, English May 2012 original only; no E/direct-drive, 321D/K, sibling/region or 2011 inheritance.; Native source inventory only; heavy-duty 251H-56 knife 20119006 is distinct and not transferred. Included/accessory status and retail substitutions require exact scope.

Source accessories list oil filter20136001 and lower knife20119002; needle6120-06quantity3.

Sources and pages

Exact gauge row

  • Exact 321C-134M-04, plain clutch-motor column, English May 2012 original only; no E/direct-drive, 321D/K, sibling/region or 2011 inheritance.; Exact plain clutch-model gauge row only, preserving full assembly context; not commerce-fitment approval or interchangeability between variants.

Needle plate20115001; feed dog complete2011401700; presser foot complete20116004; upper looper20117007.

Sources and pages

Needle and looper row occurrences

  • Exact 321C-134M-04, plain clutch-motor column in English May 2012; independent needle/bobbin/foot axes and unknown fit ceilings preserved.; Exact original gauge-row occurrences, not generic assembly compatibility, standardized mount, alternate SKU or retail-fit inference.

Needle clamp20134002; washer20128006; crank20104003; lower-looper crank20104009.

Sources and pages

Care

Reservoir level

  • Exact 321C-134M-04, plain clutch-motor column, English May 2012 original only; no E/direct-drive, 321D/K, sibling/region or 2011 inheritance.; Power-isolated access using full figure 5; oil grade/viscosity substitutions unknown.

Fill Singer Oil until indicator is between two oil-level sight-window lines, then replace the filling window.

Sources and pages

Oil change and filter

  • Exact 321C-134M-04, plain clutch-motor column, English May 2012 original only; no E/direct-drive, 321D/K, sibling/region or 2011 inheritance.; Power-isolated trained maintenance and complete section 3.3 drain/refill figures; no universal weekly oil change or invented oil quantity.

Change oil after initial four weeks and subsequently every four months; clean filter monthly or replace when needed.

Sources and pages

Cleaning

  • Exact 321C-134M-04, plain clutch-motor column, English May 2012 original only; no E/direct-drive, 321D/K, sibling/region or 2011 inheritance.; Power-isolated maintenance; source lubrication instructions apply after long disuse.

Clean head periodically with dry soft cloth and no solvent.

Sources and pages

Safety inspection

  • Exact 321C-134M-04, plain clutch-motor column, English May 2012 original only; no E/direct-drive, 321D/K, sibling/region or 2011 inheritance.; Trained inspection; electrical faults stop operation and go to qualified service.

Check safety-device adjustment, head fixing screws, belt wear/tension, overheating and cable/connector damage.

Sources and pages

New machine initial cycle

  • Exact 321C-134M-04, plain clutch-motor model, English May 2012 original only; no E/direct-drive, 321D/K, sibling, regional or 2011 technical inheritance.; Guarded running is separate from power-isolated lubrication and oil changes. The 6000 spm specification is the ceiling after the initial cycle, not a universal safe operating speed.

Run a new machine at 80 percent of maximum speed for the first four weeks. After this initial cycle, change the oil before using maximum speed.

Sources and pages

Documents

Retained original

  • Exact 321C-134M-04, plain clutch-motor column, English May 2012 original only; no E/direct-drive, 321D/K, sibling/region or 2011 inheritance.; One combined PDF counted once. Additional Portuguese 2011 edition remains separately qualified; absent 2011 English not inherited. Unknown rights private.

59-page English OEM instruction manual and parts list,P/N364336-001 Rev3May2012.

Sources and pages

Additional roles and editions

Not yet verified
  • Not yet verified: Beyond these two combined instruction/parts originals, separate accessory guide/service/schematic/brochure not accepted. Absent English2011held; no exhaustive search or publicPDFpermission.

Additional portuguese original

  • Exact 321C-134M-04, plain clutch-motor column in English May 2012; independent needle/bobbin/foot axes and unknown fit ceilings preserved.; Document presence/edition only, no Portuguese technical inheritance, supersession or cross-edition equivalence. Combined original counted once; rights private.

58-page Portuguese instruction/parts original,P/N364336-003 Rev1September2011, names this exact model.

Sources and pages

Motor

Clutch drive reference

  • Exact 321C-134M-04, plain clutch-motor column, English May 2012 original only; no E/direct-drive, 321D/K, sibling/region or 2011 inheritance.; Plain exact model clutch-column source reference; installed voltage/frequency/motor modifications are unknown. No E/direct-drive control installation or electronic troubleshooting transfer.

Clutch motor1/2HP(400W), high-speed two poles; M-type belt.

Sources and pages

Pulley frequency condition

  • Exact 321C-134M-04, plain clutch-motor column, English May 2012 original only; no E/direct-drive, 321D/K, sibling/region or 2011 inheritance.; At 6000 spm it lists 115 mm at 50 Hz and 95 mm at 60 Hz; setup reference only, never a universal pulley fit or installed electrical assertion.

The source pulley table separates50Hz and60Hz diameters at specified machine speeds.

Sources and pages

Actual installed electrical configuration

Not yet verified
  • Not yet verified: Actual installed voltage/frequency, modifications and motor configuration remain unknown.

Safety

Power isolation

  • Exact 321C-134M-04, plain clutch-motor column, English May 2012 original only; no E/direct-drive, 321D/K, sibling/region or 2011 inheritance.; Switch off before unplugging; distinguish power-isolated setup/service from guarded test sewing. Generic bobbin/shuttle safety wording is not proof of a bobbin mechanism on this overlock model.

Turn off or unplug before threading the needle or replacing needle, presser foot, throat plate, feed dog, during maintenance and when not operating.

Sources and pages

Training guards and electrical

  • Exact 321C-134M-04, plain clutch-motor column, English May 2012 original only; no E/direct-drive, 321D/K, sibling/region or 2011 inheritance.; Keep belt cover and guards installed, hands/clothes clear of rotating parts/loopers. Stop electrical damage, retain adequate cable/connectors/grounding; no wiring-box access or guard bypass.

Use properly trained operators, safety devices and goggles; fitting, repair and maintenance require trained personnel and electrical work qualified personnel.

Sources and pages

Head handling and quiet motor warning

  • Exact 321C-134M-04, plain clutch-motor column, English May 2012 original only; no E/direct-drive, 321D/K, sibling/region or 2011 inheritance.; The conditional servomotor warning does not identify the installed motor; selected plain models are the clutch-motor table column.

Isolate power for lifting or lowering the head; the manual warns that a fitted servomotor can be quiet.

Sources and pages

Service & repair boundaries

Owner numeric timing

Not yet verified
  • Not yet verified: Full needle/guard/looper service sections include standard/specific/high-lift conditions; simplified owner timing repair and universal dimensions are not accepted.

Setup & controls

Head support

  • Exact 321C-134M-04, plain clutch-motor column, English May 2012 original only; no E/direct-drive, 321D/K, sibling/region or 2011 inheritance.; Trained power-isolated installation using full figure 2; figure 3 control box/speed controller is explicitly ES DD only and not transferred.

Use the illustrated support components and residues cam; source distinguishes semi-inserted100mm and inserted about5mm needle-bed/table distances.

Sources and pages

Clutch belt and rotation

  • Exact 321C-134M-04, plain clutch-motor column, English May 2012 original only; no E/direct-drive, 321D/K, sibling/region or 2011 inheritance.; Exact illustrated viewpoint, trained power-isolated installation. Keep belt cover fitted; do not import other machine rotation conventions.

Set the head on its support, connect wheel and motor with belt and adjust roughly20mm center deflection; motor rotates clockwise as figure4.

Sources and pages

Clutch pedals

  • Exact 321C-134M-04, plain clutch-motor column, English May 2012 original only; no E/direct-drive, 321D/K, sibling/region or 2011 inheritance.; Source installation arrangement only; actual modified table/control configuration is unknown.

Friction-motor pedal is on the right and presser-lifter pedal on the left.

Sources and pages

First or disused oiling

  • Exact 321C-134M-04, plain clutch-motor column, English May 2012 original only; no E/direct-drive, 321D/K, sibling/region or 2011 inheritance.; Power-isolated lubrication/handling; subsequent observation/test running is separate and guarded. Full diagrams required, no inferred modern lubricant grade.

Do not run before oiling and confirming motor rotation; lubricate upper needle bar, guides and loopers on first use or return after disuse.

Sources and pages

Troubleshooting

Needle breakage

  • Exact 321C-134M-04, plain clutch-motor column, English May 2012 original only; no E/direct-drive, 321D/K, sibling/region or 2011 inheritance.; Possible causes, not diagnosis; timing/alignment repairs require trained service. No unrestricted thicker needle recommendation.

Table possible causes include insertion, type/condition, guards, looper relation and alignment with plate/foot holes.

Sources and pages

Thread breakage and skips

  • Exact 321C-134M-04, plain clutch-motor column, English May 2012 original only; no E/direct-drive, 321D/K, sibling/region or 2011 inheritance.; Possible causes only; silicone-lubrication advice is source-conditioned, not broad lubricant substitution or owner timing repair.

Tables distinguish threading/tension, thread-eye match, needle condition, overheating/burrs and looper timing.

Sources and pages

Uneven stitches and puckering

  • Exact 321C-134M-04, plain clutch-motor column, English May 2012 original only; no E/direct-drive, 321D/K, sibling/region or 2011 inheritance.; Trained service for knives/feed-height/timing; guarded test sewing after safe adjustments. No single-cause diagnosis.

Tables list threading, knives, feed height, tension, foot pressure, differential feed and needle/fabric match.

Sources and pages

Use

Threading route

  • Exact 321C-134M-04, plain clutch-motor column, English May 2012 original only; no E/direct-drive, 321D/K, sibling/region or 2011 inheritance.; Power-isolated threading, full figure 9 required; five-thread diagram is a separate source branch.

Follow the three/four-thread diagram for these selected models; incorrect threading can cause breakage, uneven or skipped stitches.

Sources and pages

Individual thread tension

  • Exact 321C-134M-04, plain clutch-motor column, English May 2012 original only; no E/direct-drive, 321D/K, sibling/region or 2011 inheritance.; No universal tension number or unrestricted material/needle recommendation. Test sewing remains guarded with trained operator.

Adjust each tension control for fabric thickness, thread, sewing width and stitch length.

Sources and pages

Tension control mapping

  • Exact 321C-134M-04, plain clutch-motor column, English May 2012 original only; no E/direct-drive, 321D/K, sibling/region or 2011 inheritance.; Nut 2 applies to two-needle models; nut 5 safety-stitch control is a separate five-thread branch, not assumed present here.

Nut1controls needle or left needle thread, nut2right needle thread, nut3right looper and nut4left looper.

Sources and pages

Stitch type guide conditions

  • Exact 321C-134M-04, plain clutch-motor column, English May 2012 original only; no E/direct-drive, 321D/K, sibling/region or 2011 inheritance.; Conditional source stitch-type instructions only; no unproved exact model stitch-number assignment or universal guide setting.

Needle guides1/2move down for stitch504/512/514 and up for503/505.

Sources and pages

Looper guide conditions

  • Exact 321C-134M-04, plain clutch-motor column, English May 2012 original only; no E/direct-drive, 321D/K, sibling/region or 2011 inheritance.; Full figure 12 and source conditions required; no flattened setting or exact model stitch capability inferred. Chain-looper cam is separate from selected three/four-thread configurations.

Looper guides and positions vary by stretch thread, seaming/blindhemming and stitch512.

Sources and pages

Differential adjustment effect

  • Exact 321C-134M-04, plain clutch-motor column, English May 2012 original only; no E/direct-drive, 321D/K, sibling/region or 2011 inheritance.; Trained power-isolated adjustment; selected 0.7–2.0 specification governs. Retain complete figure 14, no higher-range machine table transfer.

Relative main/differential feed movement can frill or stretch fabric; source nut1/screw2adjustment then retightens.

Sources and pages

Stitch length control

  • Exact 321C-134M-04, plain clutch-motor column, English May 2012 original only; no E/direct-drive, 321D/K, sibling/region or 2011 inheritance.; Power isolated; exact 3.6 mm specification retained. Wheel tables for other machine types do not expand model limits.

Press and hold the adjustment button, turn the wheel to desired indicated stitch length.

Sources and pages

Part numbers & accessories

These are manufacturer part references. A drawing or matching number alone does not confirm that a replacement from a seller fits. Check the model-specific listing and restrictions.

Replacement compatibility has not been checked. The original source listings below retain their exact scope.

Original parts listed in the cited source

These are source-local original references. They do not establish a replacement, supersession, adapter or retail product fit.

Source assembly and service boundary

  • Exact 321C-134M-04, plain clutch-motor column, English May 2012 original only; no E/direct-drive, 321D/K, sibling/region or 2011 inheritance.; Use exact gauge-row complete foot separately; no standard mount/shank/holder/adapter or retail fit inferred.

Source parts distinguish foot arm20101027 and shaft20102020; generic complete foot is placeholderxxxxxxxx, not a purchasable part.

Full answer and all conditions →

Singer321C High Speed Overlock Machine — Instruction Manual and Parts List · P/N364336-001 Rev3 May2012 · PDF page 58 · printed page 55 · Singer321C High Speed Overlock Machine — Instruction Manual and Parts List · P/N364336-001 Rev3 May2012 · PDF page 48 · printed page 45 · Singer321C High Speed Overlock Machine — Instruction Manual and Parts List · P/N364336-001 Rev3 May2012 · PDF page 49 · printed page 46

Oil filter and lower knife

  • Exact 321C-134M-04, plain clutch-motor column, English May 2012 original only; no E/direct-drive, 321D/K, sibling/region or 2011 inheritance.; Native source inventory only; heavy-duty 251H-56 knife 20119006 is distinct and not transferred. Included/accessory status and retail substitutions require exact scope.

Source accessories list oil filter20136001 and lower knife20119002; needle6120-06quantity3.

Full answer and all conditions →

Singer321C High Speed Overlock Machine — Instruction Manual and Parts List · P/N364336-001 Rev3 May2012 · PDF page 58 · printed page 55 · Singer321C High Speed Overlock Machine — Instruction Manual and Parts List · P/N364336-001 Rev3 May2012 · PDF page 57 · printed page 54

Exact gauge row

  • Exact 321C-134M-04, plain clutch-motor column, English May 2012 original only; no E/direct-drive, 321D/K, sibling/region or 2011 inheritance.; Exact plain clutch-model gauge row only, preserving full assembly context; not commerce-fitment approval or interchangeability between variants.

Needle plate20115001; feed dog complete2011401700; presser foot complete20116004; upper looper20117007.

Full answer and all conditions →

Singer321C High Speed Overlock Machine — Instruction Manual and Parts List · P/N364336-001 Rev3 May2012 · PDF page 58 · printed page 55

Needle and looper row occurrences

  • Exact 321C-134M-04, plain clutch-motor column in English May 2012; independent needle/bobbin/foot axes and unknown fit ceilings preserved.; Exact original gauge-row occurrences, not generic assembly compatibility, standardized mount, alternate SKU or retail-fit inference.

Needle clamp20134002; washer20128006; crank20104003; lower-looper crank20104009.

Full answer and all conditions →

Singer321C High Speed Overlock Machine — Instruction Manual and Parts List · P/N364336-001 Rev3 May2012 · PDF page 58 · printed page 55

Check the exact model and part before ordering. Missing information does not mean a part is incompatible.

Care, setup & service references

Full-manual access: this profile supplies document references and page locators, not the complete manual or its diagrams. No matching publisher file is linked here. Obtain the exact manual and read the full procedure, figures and safety precautions before following an operating or service answer. Check document access and scope →

Use the full source procedure and its safety precautions. A short referenced answer is not a substitute for service documentation or qualified electrical/mechanical repair.

Service-manual availability and service-only procedures remain unestablished unless separately cataloged and reviewed.

Coverage and source-review limits

Operating limits and original part references use the exact English model column. The Portuguese edition is listed as a document, not used as translated technical evidence. Standard interfaces and replacement compatibility remain unconfirmed.

Coverage and remaining questions

Operating manual
Listed below; check the edition and available link.
Exact OEM part application
No model-specific part application is listed here.

Still to confirm

An unanswered question does not mean a part is incompatible. We have not confirmed enough information to recommend it.

Motor — Actual installed electrical configuration: Not established Full recorded limit & conditions →

Needle — Alternate systems and special needles: Not established Full recorded limit & conditions →

Presser foot — Mount shank adapters retail fit: Not established Full recorded limit & conditions →

Documents — Additional roles and editions: Not established Full recorded limit & conditions →

Bobbin — System case dimensions substitutions: Not established Full recorded limit & conditions →

Service — Owner numeric timing: Not established Full recorded limit & conditions →

Other names, regional versions, production history, further specifications and documents are not fully covered here. Their absence is not a “none exist” finding.

Next evidence targets

  • Find additional exact-model OEM parts/service, quick-reference and accessory documents; retain inaccessible and not-found outcomes.
  • Resolve standardized needle equivalence and conditioned alternatives without deriving them from the supplied number or size.
  • Establish the exact foot/holder/adapter application and original-item substitutions; placeholders and assembly numbers do not establish retail fit.

These are research questions, not claims that the missing relationship exists.

Sources and page references

Each answer links to its exact evidence passage below. Open a reference to see the document and page. These links identify the source; they do not include the full manual or its diagrams. Document access is consolidated in the OEM library above.

Document and page references (26)

Singer321C High Speed Overlock Machine — Instruction Manual and Parts List

Published by Singer · P/N364336-001 Rev3 May2012 · English

Exact plain clutch-motor 321C models named on physical page 58; shared instructions apply only within this English May 2012 original. E/direct-drive variants and three-, four- and five-thread branches remain separate. No 321D/K or 2011 technical inheritance.

Checked against the document text.

Document and available links →About this document →

Singer321C Máquina Overloque de Alta Velocidade — Manual de Instruções e Lista de Peças

Published by Singer · P/N364336-003 Rev1 September2011 · Portuguese

Exact 321C model named in the Portuguese September 2011 combined original: document presence and edition only. No translated technical instructions, supersession, hardware, regional or English 2012 equivalence is inferred.

Checked against the document text.

Document and available links →About this document →

Editorial responsibility & corrections

Alex Shick · Founder and editor. Corrections managed by Alex Shick.

This Singer 321C-134M-04 guide is based on documents, with AI assistance to organize the information. We have not tested or repaired the machine.

Check the document edition with each answer. A source review date is not a machine inspection date or a promise that the manual is the latest edition.

Contact the SewIndex team or report a correction ↗

The correction address has been tested and its monitoring confirmed. We cannot promise a response or accept every suggested change.

Report an error with the model, document and page · About SewIndex and our method

About this information

Answers come from the documents named on this page. They describe those editions, and may not cover later changes to the machine or manual.

What the original source review covered

Source review: Reuses retained exact-model source acceptance. The independent technical review sampled 30 of 258 positive claims across six profiles; it did not independently verify every claim. A separate reader-wording review checked 48 field/model cases. Exact model columns, industrial operating limits, editions and original conditions remain attached. English supports technical answers; the Portuguese edition establishes document presence and literal edition only. Translated technical use and matching current public downloads have not been established.