Cylinder Head Disassembly/Reassembly Questions

[Guest]

Not strictly GS related, but more generic in nature. For a future project I am thinking of buying a spare head and trying my hand at some light porting work. I have never pulled a cylinder head down to bare parts and then reassembled it and have some questions.

1) If I end up with a spare head that has no cam in it can I swap in the cam from the original head with no issues? I am thinking about wear pattern/break in issues here.
2) Do I need to mark all the valves and make sure they go back into the same spot they came out of? Assuming they are all within spec and OK, that is.
3) Are there any issues with replacing valve guides and then using the original valves again?
4) I know that cam caps cannot be swapped or moved, are there any other parts that must go back in their original position/orientation?


Thanks,
Mark

 

[Nessism]

1) The cams do wear in together with the other parts in the head but you can swap things as needed.
2) Yes, it's best to keep all the valve train parts in their original location when working on the head.
3) If the valves measure correctly they can be reused
4) See 2) above.

Since you are obviously inexperienced, I'd greatly caution against doing serious head work like replacing guides and doing porting beyond just cleaning up casting flash. Any time the guides are touched the valve seats must be cut, and that's not for doing in your garage for most guys.

 

[Guest]

Since you are obviously inexperienced, I'd greatly caution against doing serious head work like replacing guides and doing porting beyond just cleaning up casting flash. Any time the guides are touched the valve seats must be cut, and that's not for doing in your garage for most guys.

The porting would be light work, not a massive change. I wouldn't change the guides myself, that would be a job for a specialty shop. Didn't realize about the seats needing to be re-cut if the guides are changed out, that would also be specialist work. It is more of an experiment/educational experience than anything. That's why I would buy a spare head, leaving the original untouched if it did turn out less than great. I've done more than enough mechanical work to not be worried about pulling the head down and reassembling it, but I have never done a full rebuild on a multi-cylinder engine, which is why the questions.

Thanks for the help, Ed.


Mark

 

[GregT]

I keep each valve assembly together - spring seats, springs, retainers and collets with their valve. Buckets too if it's an 8V.

It's actually pretty rare that you'd have to replace guides in my experience. The OHC fours have a lot more oil around the top end than singles - ancient or modern.

 

[sharpy]

Grab a few egg cartons for keeping each set together. Cheapest option. Speaking of tools, you can become one if you make a valve holder like in pic to keep them sorted Or anything between those two options.