Valve ticking on startup...
 

I had a strange one this morning. I recently rebuilt the head on my M103 motor. I have driven it 4k miles since the rebuild. I had not done anything to the rockers for the rebuild. Previous to the recondition, my valvetrain would tap for a second or two on startup until oil pressure comes up. Then it purrs like a kitten. After the work, it still does the same.

It was colder than usual this morning. About 18-19 degrees. I had changed oil on Saturday afternoon with Mobil 1, 10w-30. Now this morning, it did not stop ticking after startup. I reved the motor a couple of times and the ticking did not go away. I shut the car off, restarted, and the ticking was gone.

A friend of mine has a Mercury Tracer (Mazda 323) that does the same thing. Sometimes after startup, the valvetrain ticks. It will keep ticking until the engine is stopped and restarted. Then the ticking is gone.

What could cause this to happen?

How do I diagnose which set of rockers is causing the ticking?

Howdy MP,
Electronic contact stethoscope should be able to pinpoint which cam follower is ticking.I think you are running the right viscosity motor oil but I like to suggest adding a qt of Marvel Mistery oil next oil change it will do good for your lubrication sys anyway!

Enjoy your ride Rasoul

BTW show me any MAZDA product over 60000 miles with quite valvetrain sys. LOL

Thanks for the info..

But can anyone explain why a restart makes the tick go away?