Recapping an 8060A:
You will remove and replace 10 Caps: C1, C23, C24, C32, and C33 (100uF). C12, C21, and C28 (10uF). C36 (22uF). C19 (47uF). Suitable replacement parts were specified in post #423.
Most importantly - Clean, clean, and clean again. Do not leave flux residue. If you do not blot or blow off the IPA to actually remove the flux residue, then you are potentially making a leakage path elsewhere. (I sure miss the spray freon tanks...boy those made a clean board. I probably damaged my liver holding boards with no protection gear). I know many will think I go overboard on the cleaning, but if you want your 8060 to function in high humidity without going wonky, you will clean buddy, and you will be thorough! A lesson learned from countless hours hovering beside a humidity chamber.
On a side note, one advantage the 4 layer board gave to the 8060 that older models didn't have, is that I buried as many high impedance traces as I could in the inner layers. But they still have to come out somewhere. A practice learned at Fluke that I still follow with all my designs.
Here is the recapping process that I use. By no means the only way to do this.
(I apologize for the long length of this post and perhaps too much detail here. But not everyone doing this has your years of experience. Use good ESD practices.)
1- Once the case is open, remove the shield (don't lose the spring). Remove the LCD/SM4 assembly. Although not strictly necessary, I also remove the switch end caps, the green power switch slider, and the fuses.
2- Remove all the old capacitors. There are a total of 10 to replace. Try to not damage the pads. I always add a drop of rosin flux before attempting to remove the part. I used a Pace rework station, but the usual combo of a good solder station, solder sucker and solder wick braid will work fine too. I'm a firm believer in using a fairly large tip on the iron for desoldering. With some stubborn corroded pads, I had to use several techniques including adding new solder. You can usually tell if the cap spewed because those are the ones that are difficult to remove due to pad corrosion.
3- Using a sawed off acid brush, scrub the top and bottom of the pads with IPA (99%). Where electrolyte has spilled, the pads will be off-color and potentially heavily corroded. It is important to clean off all the electrolyte thoroughly. If the pad is heavily corroded, you might have to jumper the connection. If it appears the electrolyte has gone under other components, you might have to remove them too.
4- I use a glass cooking pan with a lid. I place the 8060 in the pan and pour IPA (not directly on the 8060) until it just covers the top of the PCA. Do not use so much that it gets into the gang switch.
5- Soak in the IPA for 30 minutes.
6- Remove the board and blow dry it with an air gun at low heat. (Clean compressed air is how I'd do it I had a compressor). At all times, hold the PCB by the edges. Avoid fingerprints!
7- Install the new caps using fine rosin flux solder (I used 27mil diameter). The standard for polarity with Electrolytics is that the long lead (before you trim it off) is positive. Most (but not all) caps have the negative lead identified with a color band. This is the case with the parts in the attached list.
8- Use a sawed off acid brush dipped in clean IPA to remove all flux residue. Use a lint free swab or q-tip to soak up the IPA before it dries. Clean each cap's pads individually so that the IPA does not dry up before you wipe it dry. Again, this is to help remove the IPA diluted flux.
9- After all your new caps are in and clean, place the PCB in the glass pan, and, using new, clean IPA, fill up the pan to just cover the top of the PCB. Leave for 30 minutes.
10- Remove the PCB and use a clean Acid brush to clean every surface you can reach (not just the new cap areas). Re-wet the board in the pan, and then blow it dry.
11- Now the wait... do not apply power until the whole assembly has had at least a few hours to dry. Use this time to disassemble the LCD and clean all the surfaces and elastomerics with a wooden Q-Tip dipped in IPA. Be gentle with the elastomerics, be vigorous with the PCB surfaces. Use lint free wipes to remove any residue while the IPA is still wet. You can also clean the LCD, Lens, and Polarizer with IPA. This should fix any ghosting or non-functional segments. Be careful not to get fingerprints on anything.
12- Reassemble the SM4/LCD assembly, screw it into the board, and now cross your fingers. Apply power and hope you got all of that nasty corrosion out. I suggest trying the ratio test first (Hold down the continuity key while turning on the unit. Hold until just 8s are showing, then release). If the ratio test is 9992 to 10008, your A/D is probably functioning properly. The other test I recommend is a turnover test. This will reveal leakage. Use any stable voltage source and see if the 8060 reads the same regardless of polarity. e.g. Put in around +1.9V with the meter in the 2V range. Note the reading to the lsd. Turn the leads around, and see if the negative reading is the same. Turn over error of 1 digit or less indicates a healthy A/D and input components. Try it again in the 200mV range with ~190mV. If this all looks hunky-dory, turn on the 200nS range. It should immediately go to 0.00. If it takes a while to get there, that's an indication of board or component leakage (or you didn't let the board dry long enough).
Since this post is getting quite lengthy, I'll save troubleshooting tips for a future post if enough people need help. The 8060 User guide has lots of info on testing.