D6H Fuel Pump

[John C.]

I've got a friend troubleshooting a D6H Sn 4GG00334 that just died on site. Operator said there was a pop and everything stopped. My guy checked all the usual stuff, air filter, fuel supply and tried bleeding the injectors. Says fuel only dribbles out when he pumps the hand pump and the same when he turns the engine over. I'm thinking there is a problem with the pump and it needs to come out. Before I tell him to do that, I was wondering of other issues. How does this pump get timed to the engine? Last time I did one of these of these it took a timing on the end of the pump shaft. Here is a photo of the pump.

 

[Bluox]

I believe that engine is pinned and the pump is pinned and the pump drive gear is pulled off the pump shaft.
The gear stays in the timing cover.
No key or timing plates involved.
Bob

 

[kshansen]

Sorry if picture quality is not good but you might be able to tell if this is your pump:

 

[PEVO]

I believe that engine is pinned and the pump is pinned and the pump drive gear is pulled off the pump shaft.
The gear stays in the timing cover.
No key or timing plates involved.
Bob

If it is like a 3204...then thats exactly the same type setup/procedure

 

[Dave Neubert]

You pull the 4 bolt cover off the side of the injection pump insert pin a drill bit will work 3/8 I think turn motor over by hand until pin drops in pull 1/4 pipe plug from under the starter area and use a long 3/8 bolt and screw it into flywheel pull 15/16 bolt of end of pump use a puller using the 2 3/8 fine thread holes in the pump gear to pop gear off. Or put a pry bar between pump and timing gear housing loosen the 15/16 bolt a few rounds and hit bolt with a big hammer wile prying back on pump

 

[361brock]

Make sure the lift pump is working before you tear into the injection pump

 

[361brock]

Lift pump has a diaphragm and spring that has been known to break causing injection pump to starve for fuel. The lift pump is part of the primer and is mechanical.

 

[heymccall]

Thinking same thing... verify lift pump operation before tearing out injection pump.

 

[John C.]

Thank you all for the information and especially kshansen for the pages. I'll get with my friend and check all this out. I'll let you know what we find.

 

[John C.]

I got to the machine with my friend yesterday and we removed the transfer pump and dismantled it for inspection. It has a rod that rides against a cam in the fuel pump which moves a piston that has a couple of what look like check valves. The photos are below. The transfer pump is the aluminum looking thing to the left of the fuel filter.

 

[John C.]

That odd looking kind of round piece is all cut up and is supposed to be inside that round carrier piece on the far right. Here is a close up. Unfortunately an iPhone is not the best kind of camera for this type of work.



The piston is a little roughed up as well but you can't feel the wear.



It's my friend's job and he is afraid there is a lot more and was expecting up to pull the pump and all the injectors. We still might but I told him to get a new transfer pump first and we will see if that will make the engine run. We have time to get to the expensive stuff later.

 

[heymccall]

 

[John C.]

Thanks for the parts page

 

[kshansen]

If you need it I'm attaching the disassembly/reassembly pages.

 

[John C.]

Super, Thanks!

 

[John C.]

My friend called me this evening after replacing the transfer pump. It did the trick, the machine is up and running now. Thanks for all the help to all those that contributed.

John C.

 

[361brock]

 

[PEVO]

stupid question: you did check your engine oil level to see if the transfer pump wasnt filling up the crankcase with diesel?

 

[John C.]

It's a good question. The oil was black and thick and apparently hadn't been changed in a long time.

 

[Gary Layton]

Cool to see someone follow thru with the solution that worked. Thanks.