Kubota D640

[elcojo2]

Hi to all genius in the forum.

I have a Kubota D640 in a boat. I am looking for advise in how to properly set up screw adjustment behind injection pump? the one that adjusts the rack position.

I am unsure if it is properly adjusted because I was messing with it. Now, under load I get some hunting but only under load and cold once warms up rans ok. I have check the fuel system for leaks, air, etc. I have replace injectors and rebuilt injection pump. I have not checked the injection timing because I just installed with original shims.

Also for some reason this engine when cold takes a few tries to start and also when starts start at lower rpm like 700 and then after a few seconds slowly goes up to 1000 rpm.

Has always done that from beginning not sure why? Any ideas really appreciated.

 

[North Idaho Wolfman]

I'll dig into how you set that adjustment.
It's not something you normally adjust.
Being out of adjustment would explain a lot of your issues.

 

[elcojo2]

Wolfman

Thanks so much. Could be the timing is wrong and might need to adjust shims. Everywhere I read i found not clear some people said usually ok with same shims some said to check.

Also do the governor springs get damage? They seemed ok to me when replace injection pump. There was a spring in the adjustment rack screw, could that one be bad


Best

 

[elcojo2]

I did a spill test and trying to get to 22.5 degrees before tdc. I am closed to 18 degrees before tdc and I have removed all the shims. I was about 15 degrees before tdc before removing 2 shims. What happen when u ran out of shims to remove. The pump has been rebuilt by a diesel shop.

Also any luck in how to adjust fuel rack to factory specs?

Anybody?

Best

 

[North Idaho Wolfman]

Wolfman

Thanks so much. Could be the timing is wrong and might need to adjust shims. Everywhere I read i found not clear some people said usually ok with same shims some said to check.

Also do the governor springs get damage? They seemed ok to me when replace injection pump. There was a spring in the adjustment rack screw, could that one be bad


Best

I did a spill test and trying to get to 22.5 degrees before tdc. I am closed to 18 degrees before tdc and I have removed all the shims. I was about 15 degrees before tdc before removing 2 shims. What happen when u ran out of shims to remove. The pump has been rebuilt by a diesel shop.

Also any luck in how to adjust fuel rack to factory specs?

Anybody?

Best

Sorry just caught your posts

If the motor was not ever worked on before, put all the shims back under the pump, and forget about them.
The timing being off as much as you think it is, is impossible, it wouldn't run.
A slow start and hunting and low RPM's could all point to bad injectors, bad glow plugs, bad injector springs, or bad injector pump control setup ( external adjustments) , or bad injector pump (rare).