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Posted by: mattillac Dec 2 2004, 01:15 AM

as posted in other threads i have a possible bad valve seat. i talked to my old man about the situation and he said it should be an "easy" fix. he said assuming the damage to the head wasn't too bad, he could machine the head and install an oversized valve seat. he works at a shop that makes alot of high tech stuff, so he has all the equipment. anyone know if an oversized valve seat is available, or even replacement valve seats available period. thanks!

Posted by: Dr Evil Dec 2 2004, 01:56 AM

Yes, they are available. Maybe Engine Builder Supply would have them. You can not just put them in, you need to set the correct crush. The crush is the difference between the hole in the head and the outer diameter of the new seat (roughly). Someone with more knowledge than me will likely bail us out now.

Posted by: mattillac Dec 2 2004, 04:40 PM

Posted by: mattillac Dec 2 2004, 09:38 PM

please, 914club engine pros, where can i get the valve seats. my old man said he can do the work if i can get him some new valve seats. please tell me where to get them:worship: i promise to post something helpful once i get this out of the way
thanks!

Posted by: Dr Evil Dec 2 2004, 09:40 PM

Call a machine shop. THey either get them or make them. Also, look up Bug patch (sp). TIV head parts should not be hard to find.

Posted by: Mueller Dec 2 2004, 10:32 PM

hmmm....i could be wrong here, but you "could" try to call the same shops that sell the replacement valves that you had been looking for

also, try Bugformance....

please bookmark the links I (and others) have provided to you

http://www.cbperformance.com/catalog.asp?ProductID=84

Not too sure if the Haynes manual describes doing this procedure or not (you do have a manual correct???)

also, here is a decent write up on doing this repair to a corvair engine

http://home.hiwaay.net/~langford/corvair/valvejob.html

Posted by: mattillac Dec 2 2004, 10:55 PM

thanks guys! i'm going

Posted by: Mueller Dec 2 2004, 11:05 PM

when it comes to certain repairs such as heads, most people go to the "professionals".....I have a set of 1.8 heads that need a little work....i have a tough time paying someone else to do the job, but by the time I make the special tooling that is required it is just not worth it for me...besides, I'd hate to launch a motor due to me screwing something up and having a valve getting "intimate" with a piston....

Posted by: brp914 Dec 2 2004, 11:07 PM

My car dropped a seat and I had a new seat installed at Ollies in Santa Ana, CA. That was 15K mi ago. So far, so good.

Posted by: mattillac Dec 3 2004, 11:02 PM

thanks again for the links everyone. but, after looking at a couple sites that sell the seats, i've not found 36mm seats, only 35.5 or 37.5 seats. whats up with that? my 75 2.0 has 36mm seats. is this just another case of me not looking hard enough

i'm really starting to consider handing this job over to a pro and just coughing up the cash, but i'll have to wait till next year before i can afford it but my old man says he can do it so i'll give him a chance first if he doesn't change his mind once he sees the heads.
and i just can't say no to free stuff.

Posted by: mattillac Dec 3 2004, 11:03 PM

specify: 36mm EXHAUST seats.

Posted by: Dr Evil Dec 3 2004, 11:31 PM

um, is 36mm your valve outer/seat inner diameter? That would mean that you need to measure the outer diameter and go slightly up from there. Just a thought.

Posted by: mattillac Dec 3 2004, 11:38 PM

good idea.

Posted by: mattillac Dec 4 2004, 12:28 AM

so i guess 37.5mm valve seat.

Posted by: Dr Evil Dec 4 2004, 01:05 AM

Now just figure out the crush tollerance. Call a VW machine shop, they should know.

Posted by: Mark Henry Dec 4 2004, 10:58 AM

I wouldn't even try this without a proper head and seat machine (about $25K). Saving a couple of bucks isn't much of a savings if it wipes out your whole engine.
I charge $40 per stock seat (Canadian)...more if I have to custom make the seat.

Also all seat material is not equal, most cheap seats are cast and total crap. How do you tell??? Take one and hammer it hard on the side...if it shatters it's cast, if it bends at least it’s steel.
BTW these cheap seats are what most parts pushers sell.

FYI using scrap heads my head guy and I ruined about a half dozen heads, before we found the proper way to install a seat in the T4 head. To much press and you will split the head...not enough and well, you know....

Posted by: vsg914 Dec 4 2004, 11:47 AM

with Mark. Doing this yourself is a disastor that WILL happen. Stop being so cheap and fix them right. it'll be alot cheaper than replacing pistons, cylinders, and god knows what else later on.

Posted by: mattillac Dec 4 2004, 12:42 PM

i'm not cheap i'm poor :finger2: and i have bills to pay. when i have the extra money it goes to my wife first , then the 914. i'd love to have a pro do the work, but it'll take me time to save up the money. i want to drive the car soon, but i dont want to do more damage either. aaaaaaarrrrrrrggggggghhhhh!!!

Posted by: Mark Henry Dec 4 2004, 01:04 PM

I know what poor is like, but if it's one seat take it to Rimco, they'll most likely do one seat for around $30US.

Then get daddy-O to do the valve job.

Posted by: Jake Raby Dec 4 2004, 01:26 PM

Its all in experience with the type 4 head..

People wonder why the work is expensive- When they screw up a 500 buck head in 10 seconds they soon figure it out.

Good heads are gonna be easier to buy soon- very soon.

Posted by: mattillac Dec 4 2004, 01:50 PM

i feel like this when i fix so much on my own (thanks 914 club) then run into a problem like this. vw valve seat engineers

Posted by: Jake Raby Dec 4 2004, 02:27 PM

Doing this work yourself will cost you money....

It takes hundreds of hours to make the profilers and other special tools to do this head work- They can't be bought.

Look at Lens site to see just a few of the ones he has made.

I have severely overheated his heads on purpose TRYING to drop a seat and had no luck...

Not a dropped seat since 1996- Not one!