Starting my top end rebuild, But now I am concerned because of this Options

[LukeD]

This thread has made me nervous
http://www.914world.com/bbs2/index.php?act=...=ST&f=2&t=33950

I have my engine ready to pull in the morning to do top end rebuild and after reading this thread about lapping the cyl to the heads I am getting worried.

I am having my heads re-built and buying new P&C's. What is the proper method when bolting the heads back on? Use seals or lap them. I have no idea how to lap somthing properly except my wife (IMG:http://www.914world.com/bbs2/html/emoticons/grouphug.gif) so what do I do? I watched Jake's type IV teardown and assembly and he made mention of not using the seals because of the buliten but didn't say anything about lapping either.

I am tempted to take my pulled engine down to my local VW shop and having them do all the work because I am scared LOL

Luke D

[John]

QUOTE

I am completely lost as to what to do with this head.

Luke,

Here is my free advice:

You were planning on sending off the heads to be rebuilt. Send them off.

They should clean them up for you and will probably fly cut the sealing surfaces (where the cylinders seal to the head).

It looks like #2 cylinder was leaking at the cylinder/head interface (carbon buildup). I would inspect the top portion of that cylinder to make sure it isn't burned or otherwise eroded or damaged.

From doing my own research on this topic, you may want to take all 4 of your cylinders to the machine shop and have all four trued (sealing surfaces squared off with respect to each other) and have them all matched in length (sealing surface to sealing surface). This will allow the newly fly-cut single head to seal up properly to two individual cylinders when the head is torqued down. I would also suggest that the cylinder base gaskets be matched in thickness to insure that the head seals properly on the two individual cylinders.

What I understand is to use the cylinder base gaskets, but omit the cylinder head gaskets.

As far as the lapping goes, I'm unsure.

On one hand, I can understand the concept of making sure that the mating surfaces will be a much better match with each other. On the other hand, can you be sure that you are holding the cylinder perfectly perpendicular to the head as you rotate and lap it into the head.

I agree that the lapping process should not remove much material and to stop the lapping process as soon as the entire sealing surface is a consistant ring.

I would think that just as important would be the cylinder base to case mating surface. While this would not create a compression leak, it could cause an oil leak.



Again, just my 0.02