1939 pickup 1/2 ton engine noise
 

https://youtu.be/LonQmvgLlsM

Hello all,
Please advice how to fix the noise showing in the shared link video.
We just change the rotor, cover plates, points and bushings of the distributor, also new spark plugs and cables.

Thanks in advance.

Re: 1939 pickup 1/2 ton engine noise
 

Not sure what your looking for. Sounds okay other the the belt squeal at the end. tighten the belts. 1/4" play. but I could be wrong. Bearings would sqeak throughout, including idling. Loose belt would not be clearly apparent till rpms slow or. Just a suggestion.


Ever hear a 80s car take off and hear a squeal. Bad belt or too loose.

Re: 1939 pickup 1/2 ton engine noise
 

Looks like you are running both an alternator and the old generator?? Try removing the belt and see what it sounds like.

Re: 1939 pickup 1/2 ton engine noise
 

Are you worried about the periodic thumping sound? If so, it sounds a little like a spark plug is not down tight. Maybe a leaky exhaust manifold gasket?

Re: 1939 pickup 1/2 ton engine noise
 

I also heard the chain jingling on the air cleaner!

Al Hook

Re: 1939 pickup 1/2 ton engine noise
 

Thank you all for the response.
I will record a new video, the noise that I am concerned is like a porncorn sound but stronger.
I think is something related to the distributor, or ignition.

Re: 1939 pickup 1/2 ton engine noise
 

It seems very slow to rev up. Is it firing on all 8? 2 plug wires crossed??
It is hard to say from so far away.
It is a good idea to use videos to communicate the problem though.

If you take a stick of wood and hold it to your ear and put the end on various parts of the motor you might be able to tell where the noise is coming from.

You could also help yourself by removing the fan belt and the chain on the filter to stop all the extra noises.

Was it running ok before you made the changes?

Mart.

Re: 1939 pickup 1/2 ton engine noise
 

Do you have any layout to change to a more accessible distributor? The original helmet style is difficult to reach and calibrate.

Re: 1939 pickup 1/2 ton engine noise
 

If you don't mind me asking, what is the chain on the air cleaner for?

Re: 1939 pickup 1/2 ton engine noise
 

Old style security...

Re: 1939 pickup 1/2 ton engine noise
 

:D gotcha. Sometimes you need that.

Re: 1939 pickup 1/2 ton engine noise
 

Thank you to all the ones that want to help!
Here are better videos.

https://youtu.be/bFmz8LQXzx8

https://youtu.be/pjdXgRF-Vaw

Re: 1939 pickup 1/2 ton engine noise
 

I'd be looking at all the plug wires. You might have two crossed. It isn't running well. Also look at the rotor arm and distributor side plates.

there can be a problem when the rotor fails and the spark goes through to the shaft.

The engine seems reluctant to rev. I repeat check your plug wires.

One question. Was it ok before you changed all the ignition parts?

The timing might be badly retarded. What you might be hearing is unburnt mixture igniting in the exhaust pipe.

Mart.

Re: 1939 pickup 1/2 ton engine noise
 

Before changing the mentioned parts, it was in better shape than now, it didn't have much power, that was the reason that we changed the parts.
Now the power is very low and with a lot of noises.

Re: 1939 pickup 1/2 ton engine noise
 

It sure sounds like two cables may be reversed...I'd start there. Almost certainly ignition related in my opinion.


Terry

Re: 1939 pickup 1/2 ton engine noise
 

Have you driven the truck yet?


I'd start with a compression check.
Then maybe send off the dizzy to bubba.
work out the fuel, lot of guys here that build carbs. CharlieNY comes to mind.


But I would do a compression check first, and drive it a bit first.