Check out my #6 intake valve.

[whiz05403]

1987 Carrera 3.2, 110K.

I had no compression in number 6. What do think may have caused this?





Obviously I will be sending off the heads, but really didn't want to split the case.

Looking for advice on what may have happened.

Thanks.

Mike

[fred cook]

Looks to me to be the exhaust valve that is damaged. Usually, when an exhaust valve has edge damage like that, it is due to a lean running condition. Of course, it could have been caused by a defect in the valve. If you were lucky, the broken piece may have gone on out the exhaust without hurting anything. Are there any damaged places on the top of the piston? If not, just send out the heads for a refresh. Looks like the valve seat will have to be replaced.

[Steve@Rennsport]

Many things can cause that that include, worn guides, bent valve, detonation (other things will be damaged as well).

Looks like your guides are shot too, as there is a LOT of oil in the port. Don't be surprised to find broken rings, as well.

[whiz05403]

Oops, you're right, that is my exhaust valve. My bad.

That does make me feel a little better that it's not an intake valve.

Hopefully the piece just blew out the exhaust.

I will be sending off the injectors and cleaning out the fuel rails.

I plan to send off the heads, pistons and cylinders for a full reconditioning, but looking for further opinions.

Thanks guys.

[Tippy]

Send them to "cgarr". Cheapest around.

[whiz05403]

Originally Posted by Tippy

Send them to "cgarr". Cheapest around.

What is his company? Thanks

[thumbdoctor]

Starts with worn valve guides then oil deposits build up on the outer edges of the valve until it starts to hold the valve open. The flame front from combustion cuts through the valve edge like a torch. Less damage is done to the valve seat because of its cooling mass of the cylinder head. There doesn't appear to be any tell tale signs of detonation.

[Tippy]

Quote de Tippy

Send them to "cgarr". Cheapest around.

What is his company? Thanks

Just PM him.

[whiz05403]

Hello again, so finally had some time to get back in the garage.

With a trip to the hardware store I came up with a nice little weapon tool to loosen the rocker shaft 5mm nuts. I used a 5mm standard socket with a craftsman 1/4 wrench and a breaker bar. Worked like butter!!






After loosening all the nuts I preformed the surgery of taking out each rocker and putting it into its proper bag. It was fun actually.

I separated heads 1-3 and the cam looks real nice. No signs of wear at all.







I will do 4-6 today and maybe even take off off my pistons and cylinders.

Speaking of pistons and cylinders. Where do I send those to be honed and replated/measured.

Ideally I would love to have a shop re-ring them for me. Breaking a ring with a ring compresser sounds too easy to do and not realized I did it!!

Any advice would be great.

Mike

[Matt Romanowski]

Check with Mark at Exotech in Plaistow, NH (www.exotechpower.com). He can do the heads, measure everything, and take care of the cylinders as well. Prices are very reasonable and he knows what he is doing. Tell him Matt sent you.