Engine help info needed

[912UK]

Hi Can I pick some brains please I am very concerned about a 912 engine that I am helping out with and want to know what you guys think.

The engine I think over heated and it was alowed to cool down before driving back it drove back fine . It was a very very hot day and I think this contibuted to the problem . The car was parked up and alowed to cool.

When I checked it out I made sure the timing was correct and ran the car to do a quick test it poped and banged but ran. So I switched off and alowwed to col (next day) I then checked the valves they were all tight so I backed them off. reset them. Now 1 and 2 reset fine. But 3 and 4 inlets where fine once adjusted but 3 and 4 Exhaust I have backed right off and I can't get the feeler gauage in to check a gap .This is because there is no gap. now ,what would be the problem I think I knew and and have a few ideas but I would like you guys to comment.

One idea from a guy I spoke to was to take off the rocker gear and shim it out then adjust the tappets but I am fightend that there is a more serious problem .

Do let me know

Cheers

M

[Morrie]

Hi Mark,

Does it turn over easily with a wrench? If so, its not siezed. I am pretty concerned that you better consider pulling the heads and having a look, the valve thing doesn't sound good.....But remember, I am a novice too....

[James in SA]

Mark, do you know the history of the engine? The valve issue sounds worrying, but unless you can confirm that the valve adjustments were fine before the overheating episode, it's difficult to pinpoint the cause.

I agree with Morrie, though, it does sound like the head's going to have to come off. Thoughts of stretching valve stems, followed by messy and expensive dropped valves, spring to mind ...

James

[912UK]

Hi Guys well the engine truns and runs put pops and bangs. So that is why I went to adjust the valves again. They were out. So I adjusted them again, but the Exhaust on 3 & $ would not adjust out. So I was concerned. Speaking to Andy Prill the 356 912 engine guru. She says the value seats are hardened so unlikely to have valve reseation and the Valve would not strech just snap.

So hmmm the heads I think will have to come off the oil that came out was OK so that's a good sign. They only way I can think of that the valves are aftermarket valves and they have stretched as they are not made in the same way as the Porsche ones.

Let you know. Either way it's not the end of the world more Bl*&dy anoying. As I am under pressure to get it fixed. I want it right not just OK well you get on with it.

Mark