Reassembly Woes: Stuck pistons

[reddirtrider]

Number 2 is in cockeyed. Try tapping the bottom of the skirt and see if you can straighten it out. Try using a small ball peen hammer if you have one.

Ah, I wouldn't strike the piston skirt with a ball peen hammer.

Those pistons are in pretty far to be cockeyed. If they are, I'd try using the handle of a ball peen hammer on the crown of the piston on the opposite side of way it's in cockeyed.

My guess is you have a oil ring that's not in it's groove and is wedging between the piston and the bore. That would give the appearance it's in cockeyed. If that's the case you'll need to bang it out as mentioned earlier. There is no being kind to animals. It's gotta' come out and you can access the damage from there. It will come out harder than going in. It's kinda' like the Chinese handcuffs you had as a kid.

[chef1366]

Look at the crank rod and the piston in post #24.
I'd say it's cockeyed.
I would "tap" not rap.

[reddirtrider]

Look at the crank rod and the piston in post #24.
I'd say it's cockeyed.
I would "tap" not rap.

Yea, but even tapping a hard metal object against a softer, possibly immovable thin metal skirt is a dangerous proposition. If it's merely in cockeyed it won't be hard to budge and tappin the piston crown is far safer.

Hey, just my opinion.

[chef1366]

How about a block of wood and a rubber mallet. I think I like that ideal better.
You're right about the hammer on the skirt.

[49er]

How about a block of wood and a rubber mallet. I think I like that ideal better.
You're right about the hammer on the skirt.

Use a piece of wood with a steel hammer to bang on top of #2 & #3 pistons. A rubber mallet onto the wood won't apply enough energy to the piston crowns.

Before you do that, pack some timber pieces between the cases and the bottom of the cylinders. You need to support the cylinders so that the impact is transfered through the piston crowns without any energy being lost by the cylinders moving. Don't be too brutal, just good firm blows to the crown areas.
You should have the pistons free in no time. You'll probably only need to re-hone the bore and fit new rings. Pay careful attention to any ring land damage that may have occurred. You can fix this by careful filing of the damaged groove.

[67fire]

I think what Chef is referring to is to hit the piston skirt with a rubber mallet and hit the piston crown with a block of wood by a steel hammer.

Eric

[49er]

I think what Chef is referring to is to hit the piston skirt with a rubber mallet and hit the piston crown with a block of wood by a steel hammer.

Eric

Maybe?

[sparki]

block the cylinder with blocks and cloth to prevent further damage.... wooden hammer handle to knock.tap/hit the crown to get it out... hit ali with wood and nothing harder as the softer material will deform to a degree.... hit it progrssively harder til it comes out as ultimately.... it HAS to come out or it'll be a paperweight.

i'll bet the pistons looks wonky as an oil ring is bent over and has create a nice solid wedge in there... only way out is to hit.... then hit harder until it pops out.

good luck

[Don-lo]

Yeah, it has to come out, but he's already been hitting it a lot. The problem is it's seesawing back and forth. I would cut a piece of 2x4 to fit tight on one side, then hit on the other. Repeat for the other side. I would also consider using jacks, blocked so they are not directly on the head or cases. A ram system for pulling dents would work well, but so would a screw type car jack, like old VWs had. 2 jacks would work best, but 1 will do if you block one side with a 2x4 like above. IMPORTANT! If you jack on one side, do not go more than 3/8" before switching to the other side. Take your time and bring it up evenly.

[ameen]

using this (the rock)

and this (yeah that deformation came from the piston)

i ended up with this




i have two new pistons in the mail, but the cylinders are fine : )

[tkent02]

So I'm guessing that big Wiseco kit is starting to look like a good idea?

[rapidray]

I read through all the pages of this & I think I may know why you had this problem. Anytime you put new rings on used pistons, you HAVE to clean the ring grooves in the pistons before you put the new rings on them. Carbon builds up in the ring grooves, behind the old rings, & if you don't remove this carbon before installing the new rings, the new rings won't be allowed to compress far enough in the cylinder to fit the bore correctly. I believe this could be why your pistons were stuck so tightly. You also should stick the new rings into each cylinder to make sure the ring end gaps are large enough. Also, never hit parts inside your motor with anything but WOOD or a plastic like nylon. One last thing, NEVER hit the skirts of a piston if they look cockeyed. If you colapse the skirt even a couple of THOUSANDTHS of an inch it will be junk. Ray.

[propflux01]

How about an update?

[ameen]

I got them out. Beat the hell out of the piston

Surprisingly, the cylinders are still fine. Turns out that it was the one oil ring on piston 2.

Rapidray, i think you are right about cleaning the grooves, i don't think i did a very good job. Any recommendations of a good method?


on a side note does anyone know what this part is? I found it on the floor by my bike while i was rebuilding the engine. Honestly i am not sure if it even from the bike or not. If nobody knows, ill put it in its own thread.



Thanks again, you guys are great!

[hampshirehog]

Looks like the contact for the gear indicator - part no. 45 here:

http://www.alpha-sports.com/suzuki_parts.htm?fpg=/spst/1982%20GS550M/26.htm