Hi, hope someone can help . Is this normal colouring or is there a detonation problem going on? cheers

 

Anyone help out?

 

Looks ok to me. What is the mileage?

JohnD

 

Thanks for replying, not sure on mileage as the engine was off ebay with no details.

Just wanted to check as the cam belt had shed six teeth and when a new belt was tested it sounded like it was running on three cylinders . When the heads were taking off for damage inspection the other bank have all black carbon build up yet the exhaust ports on this side are as you can see....

cheers Brett

 

I did think the exhaust valves were very light in colour (as in the days of leaded petrol!)
Makes you think that the valves were stuck open and have overheated although strangely, on two cylinders. The remaining plug looks cooked as well!
An engine builder such as APi needs to give an opinion.

JohnD

 

If its jumped the best it will have bent valves. You need to take them out and sppin them in a drill chuck to check for straightness. Making a judgment on the colour of the burn pattern in the chamber is not easy, as it depends really, on what the engine was doing at the time. It looks a bit on the lean side to me. but if it has been running down the road on cruise at certain revs, it will be lean, Equally if it was just after start up it ought to be rich as anything for cold start enrichment [ choke ]

So not really able to say, except check the valves, don't ignore that fact, as if a valve head falls off you'll be in very deep.

David APi