Piston won't slide into cylinder... B6 DOHC

[pauleatstoomuch]

Hi, I'm currently rebuilding my 95 B6. I've got the crankshaft installed, and I'm trying to install the pistons.
I put the rings on in the correct order, and lined up correctly. I put one in the piston ring compressor, and tried to get it in the cylinder, and it gets stuck at the first ring. Any ideas would be very helpful. I have heard some things about honing the cylinders, and other things about sanding the ends of the rings ever so slightly.

Thanks,
Paul

[94mx3precidia]

Sanding the rings on the end is call ring end gap and should not be over looked. You need to check the manual for the correct ring end gap and set them to specifications. While your there check for piston to cylinder cylearance. That plays a special part in preventing seziures(sp?)

[se7en]

hmm, sounds like you have one of those cheap ring compressors....

buy a better one, and also, you definatly have to check ring end gap...as 94mx3precidia said

um, was the engine rebored? it helps if the machine shopwas nice enough to chamfer the top of the cylinder when they rebored the block...

If it wasn't rebored, then it could just be being stubborn man, it happens, just work at it, and they will go in eventually.

Just make sure you don't bend one of those fragile oil rings(skinny ones) as the engine will burn lots of oil and still have good compression after.(A real pain in the a-- to diagnos btw)

cheers

7

[pauleatstoomuch]

What about if i compress the piston rings again, then tap the piston into the cylinder with a rubber mallet. Is it still neccesarry to check the ring end gap? I bouth the rebuild kit from importperformanceparts.net. It's the kit for my exact engine. Wouldn't the ring end gap be the right size. Also, I did not have the cylinders re-bored.

Thanks

[94mx3precidia]

you should be checking ring end gap with the ring off of the piston. put the ring into the cylinder and push it in about half way using the piston to make sure its in the cylinder square. then measure the ring end gap.

You should at least get your cylinders honed, the rings wont be able to seat properly because most likely the cylinder is glazed.

honing or boring is a good idea because on most high miliage engines they create what i think is called a carbon lip. this is where the piston tavels to TDC but the rings stop a ew mm's away from the very top of the cylinder, after a while this lip can build up and installing the pistons gets very difficult.

to get some info i suggest going on youtube. There are some very good movies on there made by professionals that explain alot about rebuilding engines.