wierd noise in engine

[f balsiger]

When I first start the engine some thing knocks until the oil is up (2 min.) Then when the spark is advanced there is an occasional CLANK! I put in a new cam spring.
Could this be the distributor drive gear?

 

[ryanheacox]

Have you gone around with a mechanics stethoscope or a broom handle to pinpoint the noise?

 

[Railcarmover]

Generally a noise that stops when the valve gallery is full (oil up) valve train or timing gear related.

 

[ryanheacox]

Generally a noise that stops when the valve gallery is full (oil up) valve train or timing gear related.

I don't know for sure but shouldn't it take way less than 2 minutes for the valve gallery to fill with oil?

 

[George Miller]

could be the center main a little loose.

 

[Synchro909]

could be the center main a little loose.

That's where I look first.

 

[Bob Bidonde]

A center main bearing issue make itself known 100% of the time the engine is running. The timing gear may be erratic. Check the easy thing first, the timing gear!



Test the timing gear by pressing the timing pin against the gear while the engine is running. Be careful of the fan! If the timing gear is loose, pressing on it should make the knocking noise go away.


Take the side timing gear cover off of the engine to check the teeth on the timing gear. Have someone hand crank the engine for this step.

 

[George Miller]

center main knock is a common thing on a model A. When they first start to get loose they will knock until the oil reaches the bearing. They will also knock a little under load if the spark is advanced. They will then get worse the more you drive it.

 

[Jim Brierley]

I agree with George. When I bought my speedster it had a very tired engine, leaked oil BADLY, and knocked when first started, until the mains got oil.

 

[f balsiger]

thanks for the info!

 

[James Rogers]

Could also be wrist pin rattle. I vote for the center main.