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1984 120G grader

56wrench

Senior Member
Joined
Dec 4, 2016
Messages
2,135
Location
alberta
if this is a sleeve metering injection pump, is there any sign of fuel leaking from the seal weep tube up near the drive end of the injection pump? Or is it plugged? It should be open and dry
 

Toxin

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Joined
Oct 12, 2023
Messages
23
Location
Missouri
if this is a sleeve metering injection pump, is there any sign of fuel leaking from the seal weep tube up near the drive end of the injection pump? Or is it plugged? It should be open and dry
No but it seems to be leaking very small amount around the governor control linkage
 

Toxin

Member
Joined
Oct 12, 2023
Messages
23
Location
Missouri
If someone pumps the hand priming pump while cranking and the engine starts then it could mean that the fuel transfer pump is not supplying sufficient fuel to the injection pump.

How about the full story.? How did this non-starting problem first start (suddenly or got worse over time) and what has been done to the engine so fa
 

Toxin

Member
Joined
Oct 12, 2023
Messages
23
Location
Missouri
I pumped the hand pump but didnt starts

I dont know how it started or when i took over job that has been through quite a few operators.the turbo was bad i replaced it.i just replaced the injectors i doubt its been replac
 

Toxin

Member
Joined
Oct 12, 2023
Messages
23
Location
Missouri
Ok the injectors helped gave it little more power,but still wont start without either.it has 15k hours on it im starting to think the rings are about gone and it not got enough compression to fire the injector.
Does anybody habe any other idea.on possible reasons why wont start without either?
 

OzDozer

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Jan 18, 2007
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Location
Perth, Western Australia.
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Semi-Retired ..
At 15K hours, I'd have to opine the engine is well worn in the rings and cylinders dept, and compression may be well down, on what it was when new.
Does it produce a lot of grey smoke when you're cranking, without ether?
 

Dave Neubert

Senior Member
Joined
Jul 18, 2018
Messages
1,670
Location
Monroe NC
but does fuel come out when under pressure does it smoke wile cranking it without either. had a customer with the same symptoms in a 615 with a 3306 rebuilt the pump and that solved his problem. just because fuel comes out with line loose don't mean fuel will come out under pressure
 

Toxin

Member
Joined
Oct 12, 2023
Messages
23
Location
Missouri
but does fuel come out when under pressure does it smoke wile cranking it without either. had a customer with the same symptoms in a 615 with a 3306 rebuilt the pump and that solved his problem. just because fuel comes out with line loose don't mean fuel will come out under pressure
Thats what i was leaning towards is not enough compression to fire injectors
 

joe--h

Senior Member
Joined
Jul 22, 2009
Messages
1,259
Location
Utah
Turbo = not fixed

New injectors = not fixed

Now you're gonna throw an injection pump at it and see if it's fixed?

STOP

Check the compression.

How much have you spent so far?

Joe H
 

OzDozer

Senior Member
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Jan 18, 2007
Messages
2,207
Location
Perth, Western Australia.
Occupation
Semi-Retired ..
Joe H is right on the mark - the simple stuff first, don't just start throwing new components on it, willy-nilly.
Do a simple crankcase blowby test using a manometer, or a little more involved cylinder leakdown test.
You have to determine whether those cylinders, pistons and rings are still providing adequate sealing performance.
 

Toxin

Member
Joined
Oct 12, 2023
Messages
23
Location
Missouri
Joe H is right on the mark - the simple stuff first, don't just start throwing new components on it, willy-nilly.
Do a simple crankcase blowby test using a manometer, or a little more involved cylinder leakdown test.
You have to determine whether those cylinders, pistons and rings are still providing adequate sealing performance.
It will push the oil fill cap out if not in all the way.the fins on turbo were gone it was useless needed replaced anyway and injector were most likely original.how many motors anybody seen with 15k hours that has had multiple operators and dont know if was properly maintained.i was hoping of avoiding engine rebuild but i dont think thats happening lol.thanks for everyones input its greatly appreciated.
 
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