Re: Thunderbolt valve clatter

Posted by Owen_Dyneto On 2011/11/22 14:30:19

I'm really curious when you say you had the rings replaced, but the heads have never been off. Sounds improbable, and you have a head (singular). There are a few exotic engines (like the first series Twin Six and the Crosley Hot Shot) where the rings are replaced from below, and though it may be possible to do yours like that, it almost seems beyond reality that someone would try. The fellow who sold you the car and said they all clatter like that shouldn't be trusted for any further information.

If the clatter is reasonably constant, at idle, at speed, under load and not, then it's not ignition timing. If it only clatters when under hard acceleration, that's possible and likely. Sure, a 6-volt timing light could care less if you have positive or negative ground. No, changing the timing does not change the dwell. No, incorrect spark plug gap isn't likely to be the cause.

It's far more likely you need a valve adjustment as your car almost certainly has mechanical lifters. Check the engine number to be sure. A valve adjustment is a bit tedious but not otherwise a challenging task.