7.3 idi thumping in intake and exhaust

[MaterIDI]

Recently finally got my idi running right after set of injectors and advancing the timing. It ran fine until today. I started it without the intake on and it is making a thumping noise from the intake and a knock kind of noise from the exhaust. Also smoke will come out of intake after you shut it off. What should I do?

 

[IDIoit]

i would pull the valve covers first and look for a broken spring.
if they are ok, i would perform a leak down test

 

[IDIBRONCO]

The smoke coming out of the intake after shutting the engine off is normal. It's just crankcase gasses that are no longer being drawn down the intake to be reburned. The thumping noise from the intake while running may also be normal. These engines do that. Did you ever try running the engine without the air cleaner on before?

 

[MaterIDI]

The smoke coming out of the intake after shutting the engine off is normal. It's just crankcase gasses that are no longer being drawn down the intake to be reburned. The thumping noise from the intake while running may also be normal. These engines do that. Did you ever try running the engine without the air cleaner on before?

Yes i have, i have never heard it before.

 

[IDIBRONCO]

I just think that it's unusual for one of these engines to suddenly start making a noise out of the intake and the exhaust at the same time.

 

[MaterIDI]

I just think that it's unusual for one of these engines to suddenly start making a noise out of the intake and the exhaust at the same time.

Everyone has been telling me its a intake valve. But i think im going to drive it until it dies.

 

[Greenie]

Upon startup my '93 7.3 IDI occasionally makes angry thumping which it always comes out of after a few seconds. The first few times it happens can sound very bad. Mines been doing this for 20 years now.