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Recap guide

Recap the Commodore 1541 and 1541-II drive

The 1541's power supply and big filter caps are the usual suspects, and one repair turned up a shorted filter cap. A shop page lists capacitors by board type, from Type 1 through the 1541-II.

Open the interactive checklist Tick off each capacitor as you replace it. It saves in your browser.

Worth a recap. Reports say it is a common and useful fix on this machine.

Which board do I have?

Boards changed during production. These notes come from the linked sources, and many are only partly documented, so check the board in front of you.

  • 1541 original long board, assembly 1540001 (Medium confidence). How to tell: Check the assembly number printed on the board; the C64 Wiki describes the original 1541 as the larger board with internal power supply. Capacitors: Retailer list: C1 and C4 1uF radial, C2 and C5 47uF radial, C56 100uF radial, C65 220uF radial, C51 6800uF axial, C52 10000uF axial; motor board has 3x 10uF, 2x 4.7uF, 1x 2.2uF, 1x 1uF, 2x 0.47uF radial. Capacitor list differs from other revisions: yes. Source
  • 1541 boards 1540048, 1540050 and 250442/46 (Medium confidence). How to tell: Assembly number on the board, per the retailer. Capacitors: C1 and C4 1uF, C2 and C5 47uF, C13 220uF radial, C16 4700uF axial, C17 6800uF axial, C46 100uF radial; motor board set as above. Capacitor list differs from other revisions: yes. Source
  • 1541C boards 250448 and 251854 (Medium confidence). How to tell: Assembly number on the board; the 1541C is the shorter board with extra case vents. Capacitors: C1 and C2 1uF, C4, C6, C13 and C22 47uF radial, C7 4700uF axial, C8 6800uF axial; motor board set as above. Capacitor list differs from other revisions: yes. Source
  • 1541-II, assembly 340503 (Medium confidence). How to tell: Redesigned board with an external 5V and 12V supply instead of an internal one. Capacitors: Mainboard 3x 10uF 25V radial; motor board 3x 10uF 35V, 2x 4.7uF 50V, 1x 2.2uF 50V, 1x 1uF 50V, 2x 0.47uF radial. The external supply is a separate recap job. Capacitor list differs from other revisions: yes. Source

Where to start

Clues from write-ups and forum threads, not a diagnosis. Low confidence means one thread or one repair; high means several write-ups agree.

  • Power supply filter caps (Medium confidence). One write-up on a power-side repair found a shorted filter capacitor, and also shows swapping the transformer and regulators for a modern SMPS. Source
  • Caps by board type (Medium confidence). One shop page shows which capacitor pack fits each 1541 board (Type 1, 2, 3 and 1541-II), including the motor control board, so check your board type first. Source

Tips, tales and maybes

Found in write-ups and forum threads. These are other people's reports, not tested by us. Check part references and values against your own board.

  • Story: ?DEVICE NOT PRESENT from a cut jumper trace (Medium confidence). A 1541 returned ?DEVICE NOT PRESENT because a drive select jumper trace had been cut, setting the address to 9. Resoldering fixed it. The same job replaced large smoothing caps with 4700uF 16V (C16) and 6800uF 25V (C17) and warns silkscreen polarity is not always trustworthy. Source
  • Tip: Blinking error LED at power-up (Low confidence). A repair guide says an error LED blinking at start points to the power supply side and suggests checking the supply voltage and parts CR3, VR2, VR1 and CR1. It says little about capacitor values. Source
  • Story: Burned head coils cannot be recapped away (Low confidence). A batch repair of Commodore drives found two of six 1541s and two Mitsumi drives had burned read/write head coils, which the author says are impractical to rewind. Four 1541-II drives only needed motor and alignment adjustment. Source
  • Tip: Recheck speed after a new belt (Low confidence). A pair of 1541 repairs reports a rusted power switch stopping a drive spinning and a hardened belt slipping, and notes a new belt often shifts timing so motor speed and head alignment should be rechecked afterwards. Source

Before you start

  • Boards changed during production. Check your board number against the guides before you order parts.
  • A mains power supply can hold a dangerous charge. If you are not trained to work on one, have a professional do it.

Guides we used

This page and the interactive bench are built from these. They have the photos and the full detail, so please read them and support their authors.

The capacitor list

We have not checked a capacitor list for this machine yet, so none is shown. Follow the guide above for your board, then add the capacitors in the interactive checklist and it builds a shopping list for you.

Skip the sourcing

While you are in there

Affiliate links. As an Amazon Associate I earn from qualifying purchases. These links only search by name. Disclosure

Steps, tools and safety

The steps, the tools in top, middle and budget picks, and the safety list are the same for every machine, so they live on one page: How to recap, step by step.

Values are shown as published in the guides above, and boards changed during production. Check the board in front of you. A recap involves hot tools and, on some machines, dangerous voltages. You do it at your own risk.

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