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Wed Jan 05, 2011 1:32 pm

Yes, the early style bolts are only threaded part way down the shank. The stretch bolts have threads nearly all the way down to the inner surface of the cap. You should have the correct bolts. Even if they used 2.1 rod cores, they would have replaced the bolts during rebuild.

David

Thu Jan 06, 2011 6:08 am

orig VW rod bolts/WBX=1.9 thread length=13MM, 2.1 thread length=22MM.

Thu Jan 06, 2011 6:09 am

orig VW rod bolts/WBX=1.9 thread length=13MM, 2.1 thread length=22MM.

Thu Jan 06, 2011 8:52 am

Interesting thing about the 1.9 vs 2.1 rod bolts. (The difference in the threaded length.) Is that the only reason that the 2.1 rod bolts are prone to fail because they have more thread length?

Thu Jan 06, 2011 11:33 am

the 2.1 rod bolts, if I understand correctly, stretch when they are torqued into place. They require to be torqued to a specific number and then another 1/4 to 1/2 turn or so.

I don't know what exactly makes them "stretch" though

Thu Jan 06, 2011 8:41 pm

vanagonjetta wrote: I don't know what exactly makes them "stretch" though

Pretty much any material has elastic properties, even steel. So, as you tighten the nut it bottoms out against a flat surface and can't go any more. Keep turning and somethings gotta give. In this case it's the rod bolt, which will stretch. I'm not sure how much it'll stretch before it finally breaks.

Here's one of my rod caps. Based on what you all have told me I've got the 1.9 rod bolts.

Whilst I've been waiting on parts I got most of the prep work done. In an earlier post I asked some questions about removing the timing gear from the crank. I ended up using my 2-jaw puller and made up a little steel plate from some 1/8" plate using a hole saw and a hack saw. I slid the plate behind the gear just to give the jaws something to grab on besides the timing gear teeth.

First, a little heat from my trusty, old heat gun:

Then the plate and puller:

It took a bit of torque on the puller and there was a little bit of a pop! At first I thought the puller popped off the plate but I realized that it hadn't and I saw the gear moving off the shaft. Yippeee!

I've since gotten all the little parts cleaned and now I'm just waiting for my bearings and gaskets to show up so I can start reassembly.

Here's my parts cleaning set-up. Just a tupperware sort of bin with some kerosene in it.

I use this one for the initial, get-the-thick-gunk-off step. Then I've got a plastic paint bucket with clean kerosene in it for the final clean.

I've gotten shipping confirmation on everything so I expect it all within the next day or two.

Thu Jan 06, 2011 9:11 pm

Do you have someone who can align bore the case for you?

Thu Jan 06, 2011 10:21 pm

I have no helpful input whatsoever, but this thread is a great read. I enjoy your writing and hope you continue to relate your Van experiences, both mechanical and road trips.

DougM

Fri Jan 07, 2011 6:47 am

The gear puller for type-1 does same on WBX's, inexpensive also.

Fri Jan 07, 2011 11:07 am

morymob wrote: The gear puller for type-1 does same on WBX's, inexpensive also.

I looked at those online. They are pretty cheap. Only problem is, so am I. :lol:

Fri Jan 07, 2011 11:10 am

JunkYarDog wrote: Do you have someone who can align bore the case for you?

My understanding on this, based on all the internet wisdom out there, is that these cases are pretty bomb proof and almost never need to be align bored. I've also heard that there are only a couple of people in the country who are set up to do this job reliably. Just for fun I do plan to put the case halves together and mike the bores just to be sure but I don't expect to see anything out of whack.

Fri Jan 07, 2011 11:34 am

Looks like I've come late to the party. Let me know if you need any assistance with any of it.

Fri Jan 07, 2011 10:15 pm

psych-illogical wrote: JunkYarDog wrote: Do you have someone who can align bore the case for you?

My understanding on this, based on all the internet wisdom out there, is that these cases are pretty bomb proof and almost never need to be align bored. I've also heard that there are only a couple of people in the country who are set up to do this job reliably. Just for fun I do plan to put the case halves together and mike the bores just to be sure but I don't expect to see anything out of whack.

Please post the results of those findings. I skipped a case split because I couldn't find someone to align bore for me here. But I'd loved to have replaced all the bearings, thats all I had short of a complete rebuild.

Fri Jan 07, 2011 11:28 pm

There's a diagram and info showing the differences between stretch and rigid connecting rod bolts in Bentley 13.30, but it's in the diesel section. It lists thread lengths as:
stretch: 25mm (1.0 in.)
rigid: 15mm (9/16 in.)

Thread length of my 1.9 rigid bolts is exactly 9/16". I noticed that the lengths morymob listed above are slightly shorter. I don't want to jack this thread but this has me wondering if the diesel and wbx used the same rod bolts? Or if my measurement is wrong.

Neat rebuild thread btw, psych-illogical. I'm actually curious if your 2.2 has an original 1.9 case, and if so, if you can tell how it was modified to accept the 2.1 (76mm?) crank. I've heard that there are some minor clearance issues when doing this.

Mon Jan 10, 2011 7:55 pm

Good question Klucz. Not being intimately familiar with the differences between the 1.9 and 2.1 I'm not real sure. I'll scrutinize the case and see if there has been any obvious grinding/clearancing.

I'm posting right now because I'm a little confused about my crank and bearings. I've been under the assumption these past few years that the GW 2.2 was based on a 1.9 engine but Ive since read that it may have a 2.1 crank in it? I'm not sure how to tell which crank I've got and subsequently which bearings to use. I ordered a standard 1.9 bearing set but in trial fitting the bearings on the crank, I'm not feeling like they're tight enough. The #1 and #4 feel a little loose but #3 feels fine. I've had dreams of having a .001" clearance engine but I'm guessing these are more like .003".

The table in Bentley on 13.53 is pretty confusing to me and I don't see discernible paint dots at the locations shown in the diagram. The diagram talks about green, blue or red dots and the table only mentions blue or red. Can anybody tell me what bearings I should be putting in this thing?

Mon Jan 10, 2011 8:20 pm

OK. It's late and I wasn't thinking too clearly (common for me :oops: ). I thought, 'hey, why don't I just go measure that?'

One of these days I'm gonna take the time to learn how to take decent photos. I measured the crank journal for #4. There's too much glare on the dial of my caliper here but it measures 1.576"

Then I measured the bearing:

This one's got a red hue to it :?
Anyway, it measure 1.579" My guess of .003" was right on the money. Seems too loose to me. It's been a few years since I've built up an engine but that seems like about the 'wear limit' tolerance one should accept.

Anybody have any guidance for me?

Mon Jan 10, 2011 8:40 pm

You need to use Plastigauge to measure the clearance. To measure the diameter of a journal on a crankshaft, you need a micrometer, a caliper will not do. I can tell your reading of 1.576 in is wrong. According to Bentley, the stock crank #4 journal has a diameter of 39.984 to 40.0 mm. That is 1.5741 in to 1.5748 in.

Mon Jan 10, 2011 9:59 pm

You can measure the crank. 1.9 has 69mm stroke, 2.1 has 76mm.

Stroke = distance between center of main journal and center of rod journal multiplied by 2

You'll also need to check the bearing saddle sizes. And a bunch of other stuff. Read this thread for starters.
http://www.thesamba.com/vw/forum/viewtopic.php?t=226771&highlight=vanagon+rebuild+book

Tue Jan 11, 2011 12:35 am

stevey88 wrote: You need to use Plastigauge to measure the clearance.

It's not a split bearing. You can't use Plastigage on it. I agree that calipers won't give particularly accurate total distance readings, but they are usually decent for comparative measurements like what he's doing.

Tue Jan 11, 2011 8:37 am

Good points all in the last few posts.

I knew that I couldn't use Plastigage on the fully round bearings hence the comparitive measurement. This morning I woke up fresh and clear minded and grabbed my micrometer, which I do trust more. The journal measures 1.5748 right at the upper spec limit. I wish I had an inside micrometer to check the bearing but I don't. I do have telescoping gages but I'm hesitant to use them because on the soft bearing surface they would likely leave a little mark which could make it difficult to return the bearings if I need to. I do trust the comparitive measurement that I did with the calipers and I do know that I'm not comfortable putting together a .003" clearance engine. I'd sure like it to be half that or better.

I've got other commitments tonight so tomorrow night I'll torque down the case and check the bearing bores and I'll measure that crank throw to determine the stroke.

Thanks again for the info.