Sticking Exhaust Valve

[Noblebenn]

Car stored for many years and only recently back on the road, fluids changed and engine running nicely but mechanic thinks it has a sticking exhaust valve diagnosed from the right hand exhaust occasionally sucking. It can be heard also.

Car has only tootled around on slow but lengthy runs since emerging from the dark and is due a check over as well as the timing and clearances checked in two weeks.

Now he has said a good thrashing sometimes releases them but i;m not overly keen on doing this until I have changed the HT leads and spoken to you guys in the know.

It is booked in to one of the respectable speed six garages for the timing etc to be checked but I like to get my hands dirty so any anything I can do in the meantime to help investigate I am happy to do.

Any thought other then new plugs, HT leads, coil pack?

[m4tti]

How did he diagnose the stuck valve, compression test, thermal gun on exhaust manifolds, removal of can cover? None of the items you suggest on the HT side will make any difference if a valve is genuinely stuck.

[Noblebenn]

He could hear that something wasn't quite correct when listening closely and then when he put his hand over the exhaust he could feel it sucking now and again instead of just blowing. He said it is sticking and not stuck.

[m4tti]

You need to do a compression test. They run a fair amount of overlap, and you do get an amount of vacuum in the exhaust tract.

[Noblebenn]

Great, it was booked in for this anyway so hopefully all will be well and its a simple re adjust. It was more a case that if there is simply work that can be done I enjoy working on the car.

[m4tti]

Have a look at the link on my profile you'll see some dodgy valves there

These engines are much nicer to work on that a lot of modern stuff.