Stuck Piston

30aadoodlebug

30aadoodlebug

Senior Member
Hey All,

So I'm almost done tearing down my 8ba for my 50 Country Squire. I have all the pistons out except for the one up front. The others came out easily, but this one wont budge. I'm wary of using the heat wrench on it because of the block. Any advice would be welcomed.
 
You want to save the piston ??
Otherwise a holesaw with a size just a tad bigger then the bottom of the ring grooves.
I added a plastic sleeve on the outside to center it and keep the teeth from hitting the cylinder walls.
Banging on pistons with the rings stuck is a recipe for breaking cylinderwalls...
 
I took a piston out with a small cold chisel on a 90cc Honda dirt bike, the bike was left in a garage that had a hole in the roof and water leaked into to carb for years. When I got the piston out the rings looked like someone had arc welded them to the cylinder wall, luckily it all cleaned up with an over bore.
 
Thanks Guys! No, I don't want to keep the pistons. I want them out. Im planning on bringing the block to J&M Machine next week and having them bore the block.
 
>>>bringing the block to J&M Machine next week and having them bore the block.>>>

If the acetone/atf doesn't do it in a day or two, let the machine shop handle it. Jack E/NJ
 
Apply heat.
 

Attachments

  • fire in thed hole 016.jpg
    fire in thed hole 016.jpg
    98.3 KB · Views: 108
Heat to cast iron is ok when you have it under control.
If you heat above a certain level and cool uncontroled the grain structure of the castiron change...a slow fire shouldn´t be and issue but something to keep in mind when bringing the big torch out.
 
i have used brake fluid and a pine stick as a wick.its a nice soft flame,heats real slow and even.works like a charm.just keep toppinf off brake fluid.
 
I have always just pounded them out with a BFH after soaking for a while. Have never damaged a cylinder wall yet.

The valves are the real ******* on these things to get out.
 
Get a drill and drill a series of holes through the top of the piston,then it will just fall out,no damage or drama.
Lawrie
 
Lawrie said:
Get a drill and drill a series of holes through the top of the piston,then it will just fall out,no damage or drama.
Lawrie
Click to expand...

This works if a guy is fearful of the maple block and hammer method. I prefer the block and hammer - quick and easy.
If the block is that weak that'll crack from pounding out a piston, I say better find out now than later...
 
If the one stuck piston doesn't show a lot of water/rust in the cylinder, then consider that the other 7 came out easily, so it will probably just take a LITTLE persuasion - not a lot of beating to get it out. Now - if the cylinder is the only one with obvious water damage, then things can be a bit tougher. I've always soaked mine with the ATF mixture and really never had much drama getting the pistons out - even with blocks that have had some water in a bore (not all rusted up - as I don't buy those!).
 
Last edited:
You must log in or register to reply here.
Back
Top