Jump to content

Zed Head

All brains on deck - an unusual problem

Recommended Posts

I had deposits on my 77 EFI on plugs 3&4. It was due to cracks in head.

The exhaust ports on 3&4 are the only two adjacent exhaust ports and heat builds there.

Maybe exhaust valve lash is too tight on 3 & 4allowing reversion.

 

 

Here is 3&4 exhibiting darker colour on cracked head (EFI):

 

plugs2003.jpg

 

image.pngimage.png

 

Edited by 240260280

Share this post


Link to post
Share on other sites

I'd be very skeptical of a plug read based ONLY on a short period of idle. The car is not driven at idle. 

Put in new plugs and GO DRIVE THE CAR aggressively for an hour, THEN read the plugs.

If nothing else you've had an hour of fun driving the car. 

Share this post


Link to post
Share on other sites

Actually, his basic problem is an idling problem.  Lots of traffic, and sitting while idling causes the plugs to load up and the engine to run rough.  A good drive and quick engine cut might offer a clue, but the problem is the idling.  I know that my old engine would start to run rough at idle, I'd take it out in the country and give it an Italian tuneup and it would idle smoothly for a while.  Then load up again.  IT was fun for a while but got old eventually.  I put my spare engine in to fix it.

246's issue is similar.  Not clear how the cracks cause the fouling though.

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

×
×
  • Create New...

Important Information

By using this site, you agree to our Terms of Use. We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.