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fraggle00
OK, first lesson, if you get frustrated - STOP and get back to work later.

Now that I've learned that, what I can I do about this:

I drilled my hole a little off-center for my intake valve guide removal ('75 2.0). Now I've got two problems

1) When I tapped the guide hole for my bolt, the threads bit into the sidewall of the head a little
2) Due to this, threads in the guide were weak and tore out
3) Got a little furstrated and tried an alternative method of banging out the guide headbang.gif
4) Bad idea as it expanded a little and cracked the head down near the intake port. I quit right away at that point and found a better alternative method. I also scarred the valve guide hole a little.

IPB Image
IPB Image

Question is: Is this repairable? I can't be the first one to have done something this dumb. Of course, the guide I knocked out went great, as well as the both exhaust guides.

The '75 2.0 heads (for a very short time) used smaller diameter intake valve guides, so I probably could have it machined up to the next size, but I'm not sure what would happen down in the intake port.

Experts??? What's the opinion out there?
Dave_Darling
I'd say weld it up and drill a new hole. Probably best to let a pro do it, though--welding aluminum and machining valve guide holes is not for the average DIY'er.

--DD
Mark Henry
Weld then ream for a oversize guide.

You did not core the guides properly. I bet you will have to ream all the bores for oversize guides. If you drifted the guides out through the VC side you went the wrong way.

If you did core, then tapped for a bolt, you defeated the purpose of coring. Coring is done to relieve the press fit of the guide for removal.
fraggle00
I figure anything at this point it beyond me on this head. I haven't started on the second yet so I'm sure that will go better with all I learned with this one...

I drifted out the guides so they exited on the rocker arm side, I think the other bores (the ones I didn't bugger up) should be OK. I tapped them from the rocker side as well.

Looks like I read too many different methods and got some of them a little mixed up.

I'll have to chat with my local VW shop and find out where I can get this welded up and re-drilled. thanks for the fast advice.
914zim
Dude, that sucks!
Good luck!!
Andy... (bought your muffler)
Brett W
you should have heated the head and bought the proper valve giude driver. You may be able to modify an air hammer to do the job better. AS fas as the cracks you can weld them it shouldn't hurt anything.
fraggle00
Brought the head to my local VW shop and they weren't willing to recommend the weld work to anyone local (Boise, ID).

Anyone here up for it or have any suggestions? I of course will pay to have the work done, I'm not looking for handouts...
Dave_Darling
FAT Performance in Orange CA. Otto's in Venice. Headflow Masters in San Diego. They should all be able to cope with it. (I'm sure Steve from Otto's will chime in any minute now... <_< ) Don't know anyone in or near Boise.

Some of the OR/WA crowd may have suggestions that are closer.

--DD
fraggle00
I've heard a lot of good things about Otto's -

Steve? You out there? PM me or someone drop me a link.

thanks
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