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
If you get no replies send a PM to HEF member "thepumpguysc". He's the resindent FIP expert.
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.
Photos of the pump & governor would help.
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
Can you provide photo(s) of the injection pump and the governor control linkage so that thepumpguy can give an opinion..?
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
Can't see the photos. I don't think you can upload *.png files, they have to be *.jpg.
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!
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.
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
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.
Not familiar with that particular pump but did find this that might be of some help, will keep looking as I have time.
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.
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.
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.
Must be I'm just missing something here, does that page show up on SIS someplace that I just fail to see?
N&P clean the dirt off your pump then take the 2 bolts off the plate the oil line is hooked to and replace the diaphragm on the plunger. you may have to replace the inner seal on the throttle shaft. good luck Bob
I don't know about what's in SIS, the list I posted was copied from the front of the 78P 3304 Vehicular Engine Parts Book.
Well just for kicks I did save that page to at least three different places for future reference! I know I have seen charts like that or maybe it was that one1 If anyone does know of some place on SIS a chart like that is available for this or some other machines please post it here. Some times information that was in a print copy seems to get missed in the conversion to online information, or just gets files someplace not readily found!
just checking to see if "thepumpguysc" is a correct member name is there a "c" at the end?? or is it just "thepumpguys" i took the top plate off and saw the diaphragm and it seems ok also took out the shaft (some manuals call it a plunger) with the notch / slot in it and spring, and cleaned it up because it seemed dirty it seems that the governor control shaft plates are engaging and prevents the throttle control to move beyond half way (the throttle position when starting)
yes sir that is the exact fuel pump and governor i have i checked out the diaphragm plunger and spring and they seem ok to me
If you pull the control shaft, linkage parts drop off the shaft.
Just a word of caution for the OP, that shaft assembly can slide out if you remove the side cover and the part circled in red will fall off the end of the shaft inside the governor. To replace the seal that is inside the housing in the area where #5 is pointing you will need to remove the governor from the pump. If not installed correctly it can have serious problems when starting engine.
Did some more checking.. Apparently that unit is set up with an oil pressure safety shut down, not an Air Ratio Controller. Information is vague on internals but if the diaphragm leaks oil could possibly migrate into the governor and pump. Still would have to get by the inner control shaft seal to leak out the outer control shaft seal. Seems pretty much as Bluox describes.
Cat sure seems to be making this one difficult to comment on without having physical parts in hand! Below should be a cross-section view of the back of the governor on this engine. I've not found a description of operation for this set-up but it appears that oil pressure works on the diaphragm #4 which in turn pushes down on plunger #5 compressing spring #6. What I'm not seeing is how this controls the position of the two plates # 7 that are keyed to the governor shaft. But even with that confusion if the diaphragm is operated by oil pressure and it is leaking I would say that it is not going to make plunger #5 do it's job and at the same time fill that housing with oil causing the outer seal #10 to leak. As I recall the section of the other sleeve metering pump governors the area where the plates #7 are located is dry, not in the oil, like the rest of the governor parts to the left in that picture I'm wondering if the diaphragm is the main part of the problem both with the operation of the engine and the oil leaking around the shaft. Note that if one decides to open housing up by removing cover #9 I would be sure to hold in on the shaft to prevent the inside parts #1, #2 and #3 from dropping off the shaft inside the governor. Some numbers that might help if attempting to remove covers and diaphragm: #4 was a 4N0610 that changes to 5N2487 diaphragm #10 seal part number 4N2786 #13 Gasket part number 4N0402
Interesting in that there is no part number call out for the inner control shaft seal. Not just for the 941 but for any of the 3304/3306 governors. Just assume it is the same as the outer seal. I'm thinking something goes in that notch in rod 5 and has nothing to do with the #7 plates. One of the pump governor combinations shows a lever and bolt (in phantom view) in that vicinity. Maybe that's the connection?
Well if you look at a different view where it shows the side view of the pump there is an arrow pointing to the inner seal but you have to know where to look to find it item #7 and yes it's the same part number:
OK, just seems it would have been easier to call out quantity -2 in the parts list. Here's what happen to the inner parts when you pull the control shaft....
Agree sometimes wish the guys putting together parts books actually knew what the parts did! Also like that picture showing the bits laying in the bottom of the housing. Helps make my point about "NOT REMOVING THE SHAFT!" I suppose if someone did screw up like that and then tried to start the engine it should not overspeed but if one of those bits did manage to fall into some other moving parts it would not be too pretty. At least as I recall the flyweights have a tin can covering them so you might get lucky! Saved that picture for future reference!
Still digging for info. Got a few more tid bits from a 4Bxxxx Industrial Engine Parts Book. Looks like linkage between speed limiter plunger and control shaft is through that flange arrangement sandwiched between the two plates. Can't get an image in my literature. The outer shaft seal has the lip facing inward (cancels some former advice I got) At this point I'm ready to conclude that this is in fact a speed limiter only , not a shut down device. I'd say it was to function like the speed limiting plunger on the compact scroll pump that proceeded the sleeve metering version. Just limits speed until/unless engine oil pressure is obtained. Need to actually get one apart and pay more attention to the limiter device which I have not run into before.
Here's are matching lists for the 3306, also helps define change from D333c to 3306
engine is a 3304 not a 3306
thank you so much for your input
thank you very much for your input
That info is for kshansen, already covered the 3304.
And it does highlight the reason those trying to help make such a big deal out of getting thing like full serial numbers! Much of the old machines systems are very close from one application to another but Cat also slipped in some of those "Gotch-yas" now and then just to keep you on your feet! Never had a personal run in with it but often times when looking in a parts book you will see at a point of change there will be a small handful of serial numbers where the old style component will be used on a newer machine. I have thought that it might have to do with someone ordering a group of machines and requesting they all be identical, say if they are going to be based in a remote location. Where I worked we were all of a 30 minute drive to a major dealer and at the worst could get overnight shipment of 90% of the parts from a Cat warehouse often for no charge for shipping. But if in the boonies where you may have to wait weeks or months for a simple part having everything identical could save lots of lost production time.