Re-cap questions: Dokorder 8140

[somethingcleveridunno]

I freed up two of the big caps just so I could read the markings. So, in this machine, how do I know which of those monster caps are motor start and which are motor run?

 

[par4ken]

Check the service manual. None listed on hifiengine Dokorder . But available here

https://www.servicemanuals.net/en/DOKORDER-8140-Service-Manual

 

[quadsearcher]

Yes, simple and correct answer is use the service manual.

It looks like the silver can cap has two caps in the package, have to look at a manual to see how they are wired (separately, parallel, one for 50hz or the other for 60hz, etc.) but the values are motor cap values and 250 is probably followed by WVAC. Motor caps are AC caps. So that is one or maybe both of them, maybe for the capstan. The other silver can cap back and to the right of the supply reel motor is a start and/or run cap for that motor most likely, the other reel motor appears to have one also (if these are ~250vAC caps), partially obscured by the harness and that blue cap hanging down.

Does the unit have a speed problem? I'd leave them there if they are functioning, but I don't know Dokoders.

The blue 50v2200 is a DC cap, likely main filter for the electronics.

 

[somethingcleveridunno]

Just to follow up, the big metal caps are film caps according to the service manual, so shouldn't need replacing. I'm gradually going thru the electrolytics and replacing them with new. Then I guess I'll have to go thru everything with DeOxit.

 

[quadsearcher]

FWIW I got my air conditioner running last week, replaced a motor run capacitor, 3.5uF at 450VAC in this case. It was a big metal cap. The fan motor was sometimes stuck on slow when it started. I wouldn't have bothered to do it if it was running OK.