L3750 Starts and runs Wide open throttle

[Wallyiii]

I replaced the head gasket on my mid 80's L3750 cylinder diesel. Using all OEM Kubota gaskets and O-rings; after bleeding fuel system engines starts and runs wide open, and will not shut off with manual slide out lever. I have to choke off the intake to get to shut off. The throttle lever is working but does not change engine speed - it is literally wide open. Any help is appreciated - What did I forget do wrong or break!

it is a old tractor and not extremely well maintained; when it breaks I fix. After reassembly I noticed my oil light does not come on with switch on. Thanks for your expertise.

 

[North Idaho Wolfman]

Did you re-attach the 2 springs that go from the rack to the governor?

 

[Wallyiii]

Ok well no but not sure I took them off, and is this a governor internal of pump; where are these springs located? do you have a link or picture? thanks

 

[North Idaho Wolfman]

Here you are, there is actually 3 springs on that model.

 

[Wallyiii]

Thanks! So I did not remove these during head R&R. They look to be internal of pump housing??? I assume they are still in place. It ran great prior to head gasket R&R . I had an under valve cover freeze plug pop out and was getting water in oil. Went ahead and pulled head to install new gasket like an idiot.

 

[Diydave]

Thanks! So I did not remove these during head R&R. They look to be internal of pump housing??? I assume they are still in place. It ran great prior to head gasket R&R . I had an under valve cover freeze plug pop out and was getting water in oil. Went ahead and pulled head to install new gasket like an idiot.

Didja have the valve train cover(front gear cover) off?

 

[Wallyiii]

no only the valve cover then head etc. not front cover

 

[North Idaho Wolfman]

Well then here are some more possibilities:
#1: Did you put a new O-ring on the oil supply tube when you did the head?
If you didn't could be that oil is getting into the #1 cylinder and it's running on that.

#2 How long did it have water in the oil?
Could have rusted up (very rare) the governor or the fuel injection pump rack and that is causing it to run away.

#3 It has a problem with the injection pump, that model has a very complicated setup for the idle and speed control, just because your moving the lever doesn't mean it's moving the rack on the pump.

In all cases I would get the WSM and look over the speed control setup.

 

[ShaunRH]

If you shut off fuel to the injector assembly, does the motor die off completely? If not, it's running on oil and you have oil getting into your cylinders somehow.

If it does die off, then NIWolfman's take is entirely correct, you have a pump/governor issue.

 

[Wallyiii]

I will check this by shutting off the fuel to pump and see if it keeps running and assume then it is getting oil into cylinder, it did sit up during repairs for couple months; it could be the internal governor is stuck - rusted that is. Thanks will get back to you guys

 

[ShaunRH]

It might take a few moments for it to run out of fuel but it should with it off.

 

[North Idaho Wolfman]

Yes it's not instantaneous when you shut off the fuel on these, as they don't use a ton of fuel to begin with.

 

[Wallyiii]

I is definitely not running on fuel which is another strange thing. it ran great prior to r&r. Now I can not get fuel to injectors. Pump is pumping to injection pump. So I removed head. The gasket film coating was a gooey mess. It has definitely been running on oil. There was an oring on the oil spout in front but it was an oring I pulled out of an oring kit since upper gasket set did not include one. I thought it looked good enough. Again I am an idiot. So now will this small oring fix this. Where can I get one? Do you guys have a link to good place? Also have a worry about the lack of fuel coming out of injection pump nozzles. What is causing this now? I did not remove anything but the pre formed lines and I covered these nozzles during work. ANy help is appreciated. So will the oil cause the actually get between head and block to cause this deterioration?

 

[North Idaho Wolfman]

O-ring P/N 15221-33700 $1.92
http://www.colemanequip.com/Parts_Detail.asp?partID=4842