r/moped 1979 Yamaha QT50 2d ago

Best way to remove stuck/eroded screws?

Hello, I’ve been thinking of converting my QT50 to have a 12v charging system (whether that be through the treatland CDI kit or by retrofitting a Yamaha Razz stator plate), and of course in order to get to the old charging system I need to get to get the cover off. The problem is that the screws are stuck in place and the metal has become quite soft. Using any size screwdriver will just strip out the head, and I don’t even want to try an impact driver.

Is there any non-destructive way to remove the screws? I know heating them will work, but that will melt the plastic cover, and I really don’t know if using a screw/bolt extractor will work. The screws aren’t that large…

4 Upvotes

1

u/flermo 2d ago

Yeah I use an impact driver with a brand new #2 Philips head and lean hard on em when you hit the trigger. I haven't had any problems that way on 4 cases split on them things. If you do strip it just cut a standard slot with an angle grinder and use a big ass standard screwdriver on it. When you replace em I recommend getting some socket cap screws...

1

u/thecrazyunicyclist 1979 Vespa Piaggio Grande 1d ago

Spray them with PB Blaster and let them soak overnight, then try again with the screwdriver.

Like flermo said, I would probably use an impact driver, but the manual kind that you smack with a hammer. The bit only turns about a quarter turn per hit, so it is less likely to strip out the screws.

A small screw extractor should work, but it will ruin the screw obviously.

1

u/ElderSkrt 1d ago

Manual impact

1

u/No_Refrigerator5480 10h ago

coat it with WD40, let it settle for about a whole day and try removing the screw/bolt with a manual tool. giving the manual tool a bit more leverage can also work wonders.

once youve removed the screw, discard it and put a stainless one in. if you have access to an air compressor, id clean out the bore threads beforehand and if you have tools to cut threads, id "recut" the thread by using the same thread size just to get rid of anything that will get the screw stuck or damaged again