cat 941B loader governor problem

[Nick & Pat]

throttle control will not pull back beyond half way point.
linkage is working properly and has full, smooth range when disconnected from governor
opened governor compartment and slotted pin moves freely when pushed down by oil pressure from the top oil line but seems to not engage with rotating portion when trying to move throttle into wide open position properly
oil and filter changed so it should not have anything to do with the travel of internal workings

when problem first started, oil pressure pushed oil from front oil seal
thought it was the seal, i changed it but still continued to leak even more
seems to be a lot of pressure building up in governor

 

[Nige]

If you get no replies send a PM to HEF member "thepumpguysc". He's the resindent FIP expert.

 

[Old Magnet]

That should be a sleeve metering pump. If fuel is leaking from the governor control shaft it's because the inner seal is leaking. The compartment behind the outer seal should be dry.

 

[Nige]

Photos of the pump & governor would help.

 

[Old Magnet]

If you pulled the control shaft out to change the outer seal, linkage parts drop off the shaft internally. Probably why your having linkage control problems now.

 

[Nick & Pat]

If you pulled the control shaft out to change the outer seal, linkage parts drop off the shaft internally. Probably why your having linkage control problems now.

i didn't have to pull the control shaft out to change the seal
i just removed the seal from the front and replaced it

 

[Nige]

Can you provide photo(s) of the injection pump and the governor control linkage so that thepumpguy can give an opinion..?

 

[Nick & Pat]

That should be a sleeve metering pump. If fuel is leaking from the governor control shaft it's because the inner seal is leaking. The compartment behind the outer seal should be dry.

fuel is not leaking from the pump into the governor
oil is leaking from the front oil seal
the engine oil pressure is staying the same and not increasing
it's about 60 psi
always has been the same

 

[Nick & Pat]

Photos of the pump & governor would help.

 

[Nige]

Can't see the photos. I don't think you can upload *.png files, they have to be *.jpg.

 

[Old Magnet]

Going to need pictures. There is no engine oil supplied to the sleeve metering pump on a 941B. Entire pump and governor runs flooded with diesel fuel for lubrication and fuel pressure is controlled.
Wasn't until later models that a hydraulic servo using engine oil pressure was added to the governor.
What is the s/n of your 941B?

 

[kshansen]

Going to need pictures. There is no engine oil supplied to the sleeve metering pump on a 941B. Entire pump and governor runs flooded with diesel fuel for lubrication and fuel pressure is controlled.
Wasn't until later models that a hydraulic servo using engine oil pressure was added to the governor.
What is the s/n of your 941B?

Yes S/N would answer many questions.


941B TRAXCAVATOR 80H05703-UP (MACHINE) POWERED BY 3304 ENGINE
941 TRAXCAVATOR 80H00001-03039 (MACHINE)
941B TRAXCAVATOR 80H03040-03883 (MACHINE)
941B TRAXCAVATOR 80H03884-05702 (MACHINE)
3304 VEHICULAR ENGINE 80H03884-05702 (MACHINE)

That's just an example of the option I see when looking for 941B infor in SIS!

 

[Old Magnet]

Even if it's an early "B" with the D330c which uses the compact scroll injection pump and engine oil lubrication there is no "Front Seal". Front of the governor has a blank cover.

 

[Nick & Pat]

Yes S/N would answer many questions.


941B TRAXCAVATOR 80H05703-UP (MACHINE) POWERED BY 3304 ENGINE
941 TRAXCAVATOR 80H00001-03039 (MACHINE)
941B TRAXCAVATOR 80H03040-03883 (MACHINE)
941B TRAXCAVATOR 80H03884-05702 (MACHINE)
3304 VEHICULAR ENGINE 80H03884-05702 (MACHINE)

That's just an example of the option I see when looking for 941B infor in SIS!

Hi fellas
sorry it took so long to get pictures to you all

 

[Nick & Pat]

Hi fellas
sorry it took so long to get pictures to you all

here are the pictures of the governor and the fuel pump
sorry it took so long to get them posted
the S/N is 80H4703
it has a 3304 engine
there is engine oil in the governor, not fuel
any help would be much appreciated
the throttle will open after engine is started but when you throttle down, it gets stuck in the starting position of the throttle being half way open and you cannot increase the throttle speed past that

 

[Old Magnet]

That is a sleeve metering pump, with air ratio controller. Totally operates on fuel and fuel pressure. That line going into the top of the fuel ratio controller senses intake manifold pressure.

 

[kshansen]

Not familiar with that particular pump but did find this that might be of some help, will keep looking as I have time.

 

[Old Magnet]

Outer control shaft seal lip faces out to keep crud out. Inner shaft seal lip faces in to keep fuel out of control section behind the cover. That's the only dry compartment, rest of governor and injection pump sees fuel under pressure from transfer pump.

 

[kshansen]

Is there a chart some where that would tell which injection pump, governor and such would be installed on a 80H4703?

I try looking in SIS and about all I can narrow it down to is sleeve metering and Pre-chamber. But when I try to look at the parts break downs there are several different governors and injection pumps and none of then has an 80H prefix showing most are either 78P's or seem to need engine arrangement number, so far I have not found where to find that number.

 

[Old Magnet]

Info can be found in the 3304 Vehicular Engine Parts book up to s/n 80H5703-up at which point you have to refer to the 941B Parts Book. Have to go the ehe Service Manual to get any meaningful information.