Saving A Ford 3910

[Birdhunter1]

I would like to know how the compression is in each cylinder, but with the pump off wouldn't I throw the timing off if I turned the engine over?

I wouldn't crank the engine until you have the pump back on, I think in the service manual it says not to as a gear can jump out of place and your timing is set now so why mess with it to have to time it again.

 

[PM Wells]

Thanks for the advice, I am going to wait until I have the pump back in place and with some fuel in the pump before I turn the engine over. I don't want to take a chance on the timing getting off, if that can happen on these engines. I am hoping that with the rebuilt pump, and injectors, and compression check will take care of the engine problem. Then I can move on to other maintenance issues.

 

[Birdhunter1]

You can crank it by hand for your compresion test without fuel in the pump, a socket on the harmonic ballancer will do it.
Or just crank it with the starter enough to do your test, shouldn't hurt a thing.

 

[PM Wells]

I had the injectors checked today, all three are in about the same condition, some fuel getting through, but not in a mist. I will be getting rebuilt injectors from D&C Diesel along with the rebuilt pump in a few days. So it looks like the Ford 3910 was in need of some new injectors along with the pump needing some work on the metering valve and a good cleanup.

 

[RickB]

You can crank it by hand for your compresion test without fuel in the pump, a socket on the harmonic ballancer will do it.
Or just crank it with the starter enough to do your test, shouldn't hurt a thing.

A compression test requires cranking speed of +- 200 rpm. That’s a little beyond hand cranking.

 

[PM Wells]

I was told that a leak down test can tell about as much about the condition of the engine as a compression test, and that I could use an old injector with the nozzle tip cut off and with an adapter for air and gages, and could be done without turning the engine over.

 

[RickB]

It will.

 

[PM Wells]

Still waiting on my injection pump to get back to me, so I can get this tractor going.

 

[ovrszd]

Good luck with this project. Look forward to seeing it complete.

 

[PM Wells]

I appreciate that, I read your post on your injection pump problem you had a couple years back, and learned a lot from that. Thanks for posting that.