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Sat Jan 16, 2010 11:54 pm

ok so ive been ...learning/doing a topend rebuild of my 1989 2.1 wbx.
things were going swimmingly...was trying to get the bottom cylinder seal off and pulled it to far off the piston..any tricks to getting it back on...ugh..piston rings in the way..

Sat Jan 16, 2010 11:55 pm

engine is out of the van

Sun Jan 17, 2010 1:04 am

Ring compressor? Remove the rings and then put them back on?

Sun Jan 17, 2010 9:05 am

I hear with a long wobble extension you can get the rod bolts off, remove the rod and piston as a unit, re-ring, perhaps new rod bearings, and reconnect the rod/piston/cylinder assembly with non-stretch rod bolts. I haven't done this but I know it can be done. It takes some ingenuity to hold things in place to get the rod back on the crank.

Sun Jan 17, 2010 9:18 am

Wait for 10c to chime in or send him a PM. He should have your best solution. In an Air cooled, I would have rotated the crank so that this piston is at TDC. then used a ring compressor to work the cylinder back over the piston. But then, I have never been inside a WBXer and there might be a better way. Good Luck

Sun Jan 17, 2010 9:52 am

No real room to put a piston ring compressor, even if you could/can, you won't see what your doing. I did once for fun using a home made adjustable big water hose style clamp, but you better know your stuff.

This is what your facing now:

Ben

Sun Jan 17, 2010 11:52 am

I have heard that Terry Kay found a type of ring compressor that fits within the tight confines of the water jacket. I'm not sure if this is true, I just remember reading it on here. Couldn't hurt to send him a PM to ask.

When these engines are assembled, the piston is intalled in the cylinder first. Then the piston is dropped down in the cylinder until it protrudes out the bottom to the point where the wrist pin hole is exposed. Finally, the whole assembly is slid onto the rod end and the pin is fitted through the access hole in the side of the water jacket. This is a difficult process, that takes dexterity, experience, and even a little luck - you're basically working blind trying to center up the pin with the small end of the rod.

The conventional fix for this would involve removing the piston from the rod, installing it in the cylinder again, and then reinstalling it on the rod. This is what I would recommend if you aren't able to find a magic ring compressor. Unfortunately, removing the wrist pins can be a real bear on an engine with some miles on it. Usually it won't slide out of the piston easily because some distortion occurs around the groove for the retaining ring. With some work, though, you can get the pin out, and then go about the rest of the operation. Patience is a virtue here, and you have to be careful not to damage the piston pin bore or rod end bushing.

As far as removing the entire rod goes, it's true that with a wobbler and a long extension you can remove the rod bolts through the cylinder base openings. However, you would have to be very careful not to drop the rod cap into the case during removal, and I'm not sure you can get enough clearance with the cylinder on the piston to get the rod back on. Because of this, I would recommend removing the piston from the rod instead of the rod from the crank.

Hope this helps.

David

Sun Jan 17, 2010 6:24 pm

The rod wobbly trick is only for tear down.
Pop the rod,pull the pin,put the rod back and go from there.

Sun Jan 17, 2010 9:14 pm

IMO, after doing this job twice its really no big deal to remove the piston from the cylinder. Make sure you have a nice set of snap ring pliers and you are good to go. The pins can be difficult to remove, but that is easily remedied by making a removal tool out of a washer, nut, and long bolt. Just make sure the washer and nut are covered in electrical tape of something soft of the like so that the piston wrist pin bore is not scored from the tool during removal. Quadruple check that the snap rings are fully seated in their grooves by rotating them in their grooves before sliding the cylinders back down.

Sun Jan 17, 2010 9:36 pm

It would be a shame to get this far into the engine without addressing the 2.1 rod bolt problem anyway. Spring for the rebuilt rods.

Mon Jan 18, 2010 6:23 am

After doing this job more than twice I don't waste time with homemade pin extractors, risking damage to the piston is not acceptable and it just takes too long.
POP THE RODS,REPLACE THE ROD BEARINGS,REPLACE THE 2.1 ROD BOLTS.
If you don't understand how to do this then you have no buissness this deep in the engine.

OilNBolts wrote: It would be a shame to get this far into the engine without addressing the 2.1 rod bolt problem anyway. Spring for the rebuilt rods.

Do what the man sez.

Mon Jan 18, 2010 9:30 am

Kaiser Soze wrote: After doing this job more than twice I don't waste time with homemade pin extractors, risking damage to the piston is not acceptable and it just takes too long.
POP THE RODS,REPLACE THE ROD BEARINGS,REPLACE THE 2.1 ROD BOLTS.
If you don't understand how to do this then you have no buissness this deep in the engine.

OilNBolts wrote: It would be a shame to get this far into the engine without addressing the 2.1 rod bolt problem anyway. Spring for the rebuilt rods.

Do what the man sez.

Echo that

echo that

echo that

echo that

echo that

Mon Jan 18, 2010 9:56 am

minsk wrote: ok so ive been ...learning/doing a topend rebuild of my 1989 2.1 wbx.
things were going swimmingly...was trying to get the bottom cylinder seal off and pulled it to far off the piston..any tricks to getting it back on...ugh..piston rings in the way..

I know the feeling, I went thru the same thing; doing just a top end to fix a weeping head gasket and pulled a cylinder off the piston.

After reading/hearing about it here, I was afraid this was going to be a showstopper. But, actually, it wasn't hard at all.

I just reached in and compressed each ring by hand as I gently slid the cylinder back on. It is tight and I may have used something other than my fingertips, like a small block of plastic, to push the ring inward. But, I didn't use hose clamps or any special tools.

It was dead simple and I didn't have problems with the two that I did. If I was to do it again (i.e just a top end w/o cracking the case), I'll pull all the cylinders and put in new rings while I was there.

Lawrence

Mon Jan 18, 2010 10:19 am

minsk wrote: engine is out of the van
This is the good part - you're half way there. A new rod set from Frank Stamos and some bearings from Van Cafe won't set you back that much and you'll be in good shape for a long time to come. Also, as long as you have the engine out, this is a good time to check the end-play and replace the mainseal.

You're actually in good shape.

For the record, I found the wrap-around ring compressor confounding. It works but I had a hell of a time with it.

Mon Jan 18, 2010 10:38 am

[quote="deprivation"] minsk wrote: ... Also, as long as you have the engine out, this is a good time to check the end-play and replace the mainseal.

So right. If you haven't watched this video at least 5 times, it is time to do so....

http://www.bostig.com/files/bostonbob&bostig-proper_wbxflywheel_install.wmv

Each time you will probably learn something new....

L

Mon Jan 18, 2010 11:37 am

Kaiser Soze wrote: If you don't understand how to do this then you have no buissness this deep in the engine.

Or, if you don't understand how to do this then this is a perfect time to slow down, study up, search the samba, buy some tools, learn, and do.

Mon Jan 18, 2010 12:07 pm

funagon wrote: Kaiser Soze wrote: If you don't understand how to do this then you have no buissness this deep in the engine.

Or, if you don't understand how to do this then this is a perfect time to slow down, study up, search the samba, buy some tools, learn, and do.
>>>>>>>>>>>>>>>rant alert<<<<<<<<<<<<<<<<<<<<<
There is a first time for everything but a halfassed job will usually result with a hole in the block.

Whenever the heads need to come off on a 2.1 it is prudent to R/R the rod bolts,rod bearings,piston rings/ hone the barrels and all the gaskets/seals that can be reached not to mention the properly reworked heads. If the engine is out do the ENTIRE clutch assembly, pilot bearing AND the trans input seal.
Nice time to do the CVs with all the extra room to move around and why not the rear brakes while it's up in the air.
Take your Bentley to the can when you go and absorb some Vanagon instructions.

Mon Jan 18, 2010 12:24 pm

Quote: There is a first time for everything but a halfassed job will usually result with a hole in the block.

Strange, i did over 40 top end, of what i know, most of them not to say all are still on the raod.

Quote: properly reworked heads.

Rework those head is a waste of time and money.

Quote: If the engine is out do the ENTIRE clutch assembly, pilot bearing AND the trans input seal.

I agree but many are on a tight budget.

Quote: Nice time to do the CVs with all the extra room to move around and why not the rear brakes while it's up in the air.

Unrelated and i'm sure his van is not in the air.

Quote: Take your Bentley to the can when you go and absorb some Vanagon instructions.

I wouldn't do that :-)

Mon Jan 18, 2010 1:30 pm

Ben,
By the heads I mean AMC with replaced valves but you knew that.
The rest is your opinion.I'm done here.

Tue Jan 19, 2010 8:35 pm

wow...lots of good info...thnax guys..
the van is in the air...im luckcy enuff to have a freind with a lift in his garage..i have free run of the place.
i will be checking cvs and all that fun stuff..
im oging to attmept to do the rings by hand...we shall see what happens..
i may jsut slpa new heads on the engine thats still in the van..
the enigine out of the van is one i bought with 70k on it..
but now i may save this for my 85 camper..