I have an MS8-26SU with vertical collapse that I was planning to send to the legend that is Grant to service.
I had some time on my hands today so started thinking I'd make some sort of start on this. Then i thought I'd post here in case it's useful for someone else, or more likely me in a few days time when I've completely forgotten what I did
I found this forum post suggesting common reasons for vertical collapse on this chassis:
http://forum.arcadecontrols.com/index.p ... msg1321569
My thinking was to check these out and leave it there if this didn't resolve the issue. I know just enough to be dangerous, so don't want to make a bad situation worse.
Now that my Sunday afternoon had a mission I disconnected the chassis and brought it over to the bench. In brighter light a visual check of the board reveals a number of failed components in one area of the main board that will need addressing first:
R422 is roadkill - I have another MS8 with this resistor intact and I believe this is a 1/4w 0.41K
R451 is scorchio - service manual says it's a 1/4w 4.7K
C454 is kaboom
C913 is bulging at the top
Other than these the only thing that seems wrong from a visual inspection is the rectangular cap C901 (above main fuse F101) has a fair amount of play that suggests it needs resoldering. I'll do a visual and crack out my multimeter for any obvious bad solder joints at this point too.
I don't have any 1/4w resistors so have ordered some of these today. I can double check my identification of R422 is correct when they arrive as I've picked up a bigger kit with various value resistors, which always seems the cheapest way to buy these as a hobbyist. I found myself wishing for a nice list of component values in the service manual but was grateful for the work from the community on cap values and maps for this chassis. I have a cap kit to hand for this chassis so all covered here.
Will post my progress, or lack of
, on the thread as I swap these components out, hopefully next week when the resistors arrive 
https://drive.google.com/file/d/1GzPGAU ... drive_link
https://drive.google.com/file/d/1AIX-rH ... drive_link
Have a great evening everyone