Author Topic: Ahh crap, more troubles (11MM head but 12MM Block) (Read 2307 times)

patracy · « **on:** October 16, 2007, 05:11:58 pm »

So I had a day off and I spent it working on my truck and working on the bottom end of my engine today. I got a few more things done. But I began working on the head and found out something bad. The head they sent me was a 11mm head. My block is a 12mm. I've been researching here and I see the 11mm head bolt holes can be bored out larger to fit without issue. However, I seem to have a different problem. The oil return passage in the middle of the head (the single one, not the two outer ones) seems to be much smaller than the return passage on my block.

I played around with mocking it up. I took some of the old head bolts and made dowels out of them to center everything up. But I can see light through the oil return.

Anyone else dealt with this? I'm thinking I'll run the head to the machine shop. Have them bore the holes out larger and surface the washer lands out larger to accept my bolts. But the only "fix" I can think of for the oil return passage is to have it welded up to build it out. I took some pics, but the camera isn't charged at the moment. I'll post them up soon.

patracy · « **Reply #1 on:** October 16, 2007, 06:50:54 pm »

Ok researching this further, I believe I've got a 1.5 head!

I saw a comment in a thread about a 11mm head on a 12mm block that 1.5's had a small oil return. So it appears that if I'm going to make this work I'll have to build up the head with weld. I've also been checking a few other things. The precups are slightly smaller on this head. So I guess that means it'll raise my compression. So I've thought of another less invasive fix for this. Machining a sleeve to silicone and press into the block. This would take care of the outer ridge that's "open". I since it's not a pressure seal, I don't see it being a problem.

If I'm right about the precups raising the compression. I see there's a 5 notch head gasket for it. That should bring it back down to a normal level. BTW, I live in the south, it rarely drops below 20F. So cold starts won't be a problem.

patracy · « **Reply #2 on:** October 16, 2007, 07:05:28 pm »

Ahh! A $10 fix to be had!

http://www.vwdieselparts.com/1.5-1.6.htm

Can anyone confirm the precup issue for me? Will the smaller precups increase my CR? I guess I'll order a 1.5 head gasket too while I'm at it.

patracy · « **Reply #3 on:** October 17, 2007, 04:22:42 pm »

50 views? No comments?

blkboostedtruck · « **Reply #4 on:** October 17, 2007, 05:55:14 pm »

well you did a good job figuring out your own fix! to me it did sound like you had a 1.5 head but was not sure because you had no pics. of your project in question!
thanks Duane