TheSamba.com :: View topic - broken main bearing -> 1.9L bottom end blues

Sun Mar 30, 2014 5:47 pm

oh dears. it was a beautiful sunny day, and i was optimistically putting my engine back together. then i looked behind the shims.

i suspect this is the main bearing - or was.

there was no thurst washer - just the oil seal (leaking - no surprise!) and three shims and the horror shown above.

i guess i need to split the case now? and order all the bottom end bearings.

or is this the kind of thing that should make me start shopping for a new engine.

Sun Mar 30, 2014 6:02 pm

Picked out some shards

Sun Mar 30, 2014 6:04 pm

Sorry, that's toast. Bummer

Sun Mar 30, 2014 6:12 pm

It does look to me like it will need a rebuild. Those shards you pulled out look like the old thrust washer. It looked like this at one time
http://www.van-cafe.com/home/van/page_1586

Sun Mar 30, 2014 6:14 pm

So how did it run other than leaking oil?

Sun Mar 30, 2014 6:43 pm

I believe that is a 1.9 we are looking at. That would have looked like this...
http://www.van-cafe.com/home/van/smartlist_259/main-bearings

The thrust is built into the rear main bearing like the air cooleds.

Still, it is shot and will need the case pulled apart and examined closely.

Never seen this happen before.

Sun Mar 30, 2014 6:47 pm

Just curious...

What would cause that to happen? I have never seen that one before.

Sun Mar 30, 2014 7:04 pm

From the OP, it sounds like the flywheel might've been installed (after the last clutch swap?) without any thrust washers and/or with the endplay improperly set.

Sun Mar 30, 2014 7:11 pm

Maybe prying hard on the crank pulley to get it off?

Maybe engine fell of a jack onto the flywheel?

Maybe thirty years of clutch pressure on the thrust bearing?

Maybe aliens?

Sun Mar 30, 2014 7:19 pm

Be curious to see what the face of the flywheel snout looks like

Sun Mar 30, 2014 7:30 pm

ha. those aliens.

before i took it apart, the van was running ok - not using any significant amount of oil. some oil leaks but not pissing out. the main issue was coolant backing up into the overflow - suspected compression leak. the teardown started with a hopeful (naive?) 'just do the head gaskets in the van' with the hope to fix the compression leak (no typical wasser leak, heads not pitted) - but with one cylinder stuck (cyl #1 - compression leak cullprit?) and subsequent rings popping out, the engine came out.

at the same time, there was something up - both the main seal and the trans input seal were leaking. the engine would shudder like mad if you didn't rev the engine before engaging the clutch - but that could just be the oily clutch plate or the busted mounts - which i have now seen to.

i wonder if i did this. i did use a wobble bar to jam the pulley wheel when i loosened the flywheel nuts. i did try to be gentle, but perhaps i crushed it doing that.

the shards show above are what i picked out of the first image (a few of the outer parts of what i guess is the main bearing). i'm not sure it is the thurst washer (or where that went) because the busted thing has those triangle marks on it (those are on the main bearing right?)

found someone else who had similar pics: http://www.thesamba.com/vw/forum/viewtopic.php?p=6723502

i've already replaced the rod bearings, i guess it is now for a few more feet down the rabbit hole.

so, i order a main bearing set, split the case, pop them in, then i can start putting it back together? this is my first crack at going inside the engine.

Sun Mar 30, 2014 7:45 pm

also, yes, 1.9 - and thanks x00x - good to know the thrust washer was built in and not just something missing.

here is the snout shot - no 'fingernail' catching groove, but some wear.

flash

noflash

and here was my first sign of trouble - saw this just after i pulled the main seal a few weeks ago. this 'crumb' was hanging out behind the seal - i only looked behind the shims today.

Sun Mar 30, 2014 8:13 pm

Randy in Maine wrote: Just curious...

What would cause that to happen? I have never seen that one before.

pretty good answer here: http://www.thesamba.com/vw/forum/viewtopic.php?p=5035902#5035902

Sun Mar 30, 2014 10:49 pm

Wowee! That sucks!

Mon Mar 31, 2014 7:36 am

Looking at the shards, they look like they were there when the engine was still running. So, it is unlikely you broke it.

You will really want to examine the case where the thrust bearing seats. It is likely the case is damaged, since that is what supports the thrust lip. At one time you could buy bearings that had a thicker thrust face to work with the case that has had that surface refaced, not to be confused with alignbore. I don't know if those are available for the WBX case.

The face of the flywheel snoot, needs to be baby butt smooth to not tear up the shims and to get an accurate end play adjustment. I don't suppose you measured the endplay before you took it apart? Normally you'd want to know that prior to removing the flywheel on a used engine.

Mon Mar 31, 2014 9:43 am

thanks rsxr. so if unlikely i broke it, i wonder how likely i can fix it.

of course, no, did not measure the end-play. didn't have the equipment and only spent time thinking about how to rig something up to use my vernier calliper to do it. boo. i did much around pushing it in and out before pulling the flywheel off. it moved a fair bit. i'll go measure .005" and see if that equals 'a bit' according to my memory. (precision!)

i'm pretty dismayed at the moment. there are not many posts on here of the non-pros doing the bottom end. i found a good series of posts from deprivation http://www.thesamba.com/vw/forum/viewtopic.php?t=350303 with lots of useful info in it.

part of me says go for it. split the case, replace the cam and main bearings, and stick it back together again. HOW HARD CAN IT BE (hahaha). i had been very careful to not disturb the distributor during my top end rebuild because i didn't want to mess with timing, but sounds like i'm in for the full meal deal now.

i'm trying hard to see the practical/realistic way through this. (other than new engine - which might just be the best option).

before i go order any parts, i guess the next sensible thing to do would be split the case and see how bad the case supports around the bearings are damaged. i have a bench mountable stand adaptor - the kind not on an engine stand. i guess i will look at rigging that up, mounting the engine and
seeing what is in this kinder surprise.

Mon Mar 31, 2014 10:18 am

I would think if you have some aircooled bug experience under your belt, a WBX bottom end would not be that much more complicated. Like everything, stay clean, organized, and take lots of photos.

I have done some amazing repairs with JB Weld. If the case is beat, most likely only one half is beat. The other half should support the bearing. If you were inclined and machining the seat and an oversized bearing is NLA, you could clean the case well, smear some JB weld into the case area apply a thin film of mold release to the bearing shell, assemble the halves with the bearing in place torque the case up and let it cure 24 hours. Disassemble and if all goes well, you have saved the case, but I would never admit to trying this.

Mon Mar 31, 2014 10:31 am

I have wondered what it would take to convert a 1.9L case to either use a 2.1L thrust bearing or a similar custom made one? Seems like it would be simple enough to do. I have wondered why none of the Type 1 aircooled guys have given this a try (maybe they have???) as the thrust bearing is one of the biggest Type 1 weaknesses.

Mon Mar 31, 2014 11:03 am

I guess we know why VW soon changed the wbx to the main bearing design with separate thrust washers?

As an aside, while we in north america tend to think about differences in clear terms of 1.9 vs 2.1 the fact is VW continued making 1.9 wbx engines all the way to the last 1992 models and used the same parts for both when possible. So what we call 1.9 stuff is often really only early 1.9 and many 1.9 engine T3 vehicles share things with what we think of as only 2.1 parts, like the later case, main bearings, stretch rod bolts, all cooling system stuff.........

Mark

Mon Mar 31, 2014 11:19 am

rsxr haha... i guess i'll open it up and see what i'm looking at first.

i have a bench engine mount - i need to affix it to something, then i'll crack it open. i am working makeshift in a gravel driveway w/ tarps. :/

i haven't done any aircooled or other bottom end work, but i am interested to have a go.