1100 lift pump

[dtkraj]

I have an 1100 that likes to die after about 15 - 20 minutes of plowing snow, I loosen the two bleeders on the injector pump and squeeze the lever on the lift pump about 50-60 times till fuel without bubbles comes out, shut the bleeders, crank her over and away we go . I know air has to be getting in somewhere and I will replace the filters and check all the connections. My main question is about the priming lever on the lift pump, it feels like it only pushes fuel at the very end of its stroke and not much at that. As far as I know this may be the original pump, it has around 7500 hours. I am thinking that for 53 bucks I should probably just replace it right away but will start with the filters and go from there.Should it push fuel throughout the entire stroke or is this normal, this is our only diesel so I have nothing to compare to but it doesn"t seem right to me, Thanks.

 

[Eric in IL]

This is just a guess, but it may depend on where the camshaft is in its rotation. If the lift pump is on top of the lobe it may not have much useable stroke on the lever.

 

[Anonymous-0]

Had a similar issue with my 1100. One of the check valves in the lift pump had worked loose in the socket. Re-staked it in place. Problem solved.

 

[dtkraj]

I just came back from looking it over in the cold. I cleaned it off with shop towels and the air compressor. The gasket between the two halves looks wet with diesel fuel and I was able to tighten up all six screws easily about 2/3 of a turn if not more and I didn't really torque them much at all. I hope this was maybe the problem - seems to good to be true but if it was leaking fuel it could suck in some air right? I may have to take it for a cruise tomorrow to see if worked. If it does it again I will try to roll the engine a little-never thought of the camshaft. Check valve sounds like a good idea too - I didn't think you could do much to these pumps, that you just replaced them. Thanks for the ideas.

 

[DavidP, South Wales]

Hi, Good advice given but I would add that it would be worthwhile slackening the screws on the pump top again. The pumping lever should be held in the 'full pump' position and then the screws retightened. This will load the diaphragm equally. If its an old one there is danger of it being too tight on one side and possibly tearing.
It is quite possible that one of the valves has become partly dislodged. There is a gasket under each valve but if care is taken to stake the surrounding aluminium a small punch ground to a square of about 1/4" and then ground at an angle so that you have a diamond point. The valve can be sealed fully if held tight. The cap should be supported on two blocks of wood or in the open jaws of a vice. When you have it assembled remove the inlet and outlet pipes and operate it. Place a finger over the inlet and you shopuld feel the suction. Also just operate the pump with the lines disconnected and you should hear something like a 'donkey' sound as the air is drawn in and sucked out. In the coming days check the engine oil more frequently to ensure that the diaphragm has not ruptured and fuel is leaking into the oil.
The photo shown shows the inlet valve in place.
DavidP, South Wales

 

[Anonymous-0]

If supply pump is OK, check filter base for small bleed oriface that could be plugged. Could be a straight fitting or a banjo fitting, but usually has a small line that will go to injector return. 9B series with double filter base will be straight fitting, remove line on top of fitting, work supply pump, fuel should shoot out of approx .020 inch hole in fitting, is designed to bleed air from filter base so no air will get into injection. C.A.V. DPA pumps are not designed to handle any air in system and will die, have seen this happen several times in years past.

 

[dtkraj]

The 1100 died on me three times today, I parked it and the 2520 gets to plow snow now. I,ll clean up everything best i can and change filters and the lift pump. We've had the tractor for 25 years and 4000+ hours and the pump has never been touched by us, Dad says just replace it. When I order the parts I'll order a manual for it too- from an area massey dealer. Today the tractor was fine at lower rpm's and idling, when I cranked it up it was fine for about 15-20 seconds then it started to lose power and died. The first pump of the lever would be good, second one less and after that just a little bit at the end of the stroke felt like it pushed fuel, if i waited a while it would get a good pump in again and then less again after that. Maybe the line from the tank to the pump is clogged?, there must be a screen in the tank i' m guessing.

 

[Anonymous-0]

May need to drain right tank, should have a screen on plug that fits over inlet line that may need cleaned. If OK, check supply pump by removing output line to filters and work hand primer, if stroke is short, bump starter to move camshaft lobe away from internal arm for more travel. Should have good flow if pump check valves are in place. If not, take it apart to see if it can be fixed. May need to replace complete unit. Dad has 1971 1100, has had 2 pumps in years past.

 

[dtkraj]

I have drained the tanks twice to replace the park pawl, hope to avoid that, tanks are chuck full. Dad says replace the pump and filters first- his checkbook so okay. I ordered a dirty-greasy-well used shop manual on e-bay last night for 18$ shipped. Maybe this weekend i'll change it,doesn't look hard but i bet something will leak on me. Thanks for the tips, will report on success or aggravation.

 

[dtkraj]

I fixed it!!, but i'm not sure how exactly. The screen in sediment bulb had a little gunk on it and was torn, old pump seems to work off the tractor but new one primes with every stroke. on the filter side the drain petcock has a bad rubber washer and still leaks, will get one tomorrow. The rear filter bolt that you loosen to take off the filter is under a return fitting from the injectors so you can't pull it out without undoing the fitting- I'm lazy and thought that little o-ring under there is probably ok so I didn't bother with it. well I started filling up the filters with the new lift pump and by golly bubbles started coming out of there, I bet that little o-ring hasn't been changed in years by the looks of it when I took it out and replaced it properly instead of being lazy. The tractor ran perfect plowing snow, I bet that o-ring had been letting air in as the petcock leaked so I'm not really sure which thing fixed it but i'm happy either way. Now on to the 2520 alternator that puts out anywhere from -1 up to 19 volts and the 10,000 hour carb. This old machinery will turn me into a decent amateur mechanic yet- maybe.
Thanks for the help!