Hi All, Here's my story. I'll start for the beginning. Machine was stalling, classic govenor seal issue. Had the pump rebuilt. Done by a professional shop. I did the timing line alignment before removing the pump. Reinstalled the pump. Ran perfect no stalling. Checked the oil after the first time I ran it and the level was high. Fuel getting into the oil. I must have rolled the seal. I got new seals and the compression tool to help with reinstall. Removed the pump, compressed the seals and pump went back on the shaft with very little resistance. Put everything back together. I did have some leaks on the banjo bolts, but got that fixed. After that the machine was having the same stalling issue. Let it sit for a while and it would run about 50 seconds or so and stall. Start immediately and it would run for about 10 seconds then stall. Was thinking it might be fuel restriction, so I did a line directly from a gas can to the pump. Still the same stalling issue. Removed the return line to see if it would still run, still stalls. Here's what I observe on the stalling issue. - start machine. Starts immediately. Surges a very short time then smooths out. Runs fine. Then it seems like it starts to lose power, almost like it is starved for fuel. Gets weaker and shuts down. Almost like you are pulling the shutoff choke slowly. I also checked the shutoff cable to make sure it is fully extended and it is. I'm at a loss at to what could be wrong. The thing that puzzles me is that it ran fine prior to the removal and reinstall of the pump to correct the umbrella seal issue. I did not try to start the machine of move the injection pump in any way. The removal and reinstall were all done the same day (I was sore the next day :-( What could be the problem?? Don't make me send her to the scrap yard. Thank you!!
Didn't those engines have a Stanadyne pump on them? I don't know if it's your problem and you didn't mention it, but I recall when you pull those pumps from the shaft to replace the umbrella seal you first have to pull the throttle lever on the pump fully open and tie it back with tie wire, otherwise the governor counterweights fall out of proper position.
I think mine is a DBGFCC431-63AJ Roosa Master. I think Stanadyne bought Roosa Master later on?? Either way, I did not tie back the throttle lever on the pump prior to removal. Could that be the issue? I'm wondering when it got sent back to me I don't recall the level being tied back. I just installed and it worked fine (other than me rolling the seal).
Is this a John Deere 480C forklift ? If so check the return fitting in the cap of the injection pump. It can get plugged with pieces from the retainer inside the pump and when the case pressure in the pump housing equals the transfer pressure fuel can't flow into the head and rotor and the engine will die. It should be a check valve with a glass ball and spring. Take a pin punch and a hammer and remove the ball and spring. You may have to have the pump repaired at some time but they'l usually run like that for a long time.
If the umbrella seal was rolled you'll probably have to get the pump repaired anyway. A rolled seal; usually damages the bushing in the pump housing.
It's a Case 480C. I had the pump rebuilt with the Stanadyne 29111 Solid Weight Cage Upgrade Kit. I also put in a new check valve when I put the new pump in. After I replaced the seals and it started stalling again, I removed the check valve to see if any debris and it was clean. I also cracked the return line and started the machine. It still stalled. No difference.
Thanks for the reply. One note on your theory. The machine was only run a short time with the rolled seal. Maybe 30-50 minutes. After that I checked the oil because I was concerned about the seals. There was fuel in the oil. I parked the machine and had to wait until I had time to work on it. When I finally got time, I started the machine and drove it into the garage. Started and ran fine. No stalling. Maybe ran if for a few minutes to get it into the garage. If the rolled seals damaged the bushings in the pump, wouldn't it have stalled when I tried to move it into the garage?
One other thing I thought of. When I removed the pump and looked at the rolled seal, the seal had a brass shine on it. Not alot but enough to notice it. Could that have damaged the bushing and caused a pressure issue?
If the seal cut a groove into the bushing the seal might roll when it slides past the groove. If the seal is rolled fuel will get into the engine oil. You can try to clean the bushing up with emory cloth and it might not roll the seal.
The seal being rolled could have caused the transfer pressure to drop below what it needed to run. The only other thing I can think of would be if poppet in the tip of the injection nozzles was stuck open that could allow compression to get into the pump and cause it to die. If the seal being rolled was the problem it shouldn't have ran to get it into the shop. If it's still cutting off try loosening an injector line and see if any air bubbles ar in the fuel. If there's air in the injector line but not the return line you probably have a poppet sticking open in one or more injectors.
Rolling the seal is not uncommon & running the engine for a day or two to find that you've done that has been done by many people - been repaired - without any future issues. Did you make sure the fuel return line back to the tank is clear? It could be plugged up with flex ring turds from before the pump was repaired.
I’ve seen this problem 100x.. Old flex ring material is hiding in the return line.. Follow the return line up.. it T’s into the INJECTOR RETURN LINE.. the f. ring material is hiding in THAT LINE & will come out at the most inopertune time.. Separate the lines (returns).. Remove the tank cap. Using compressed air, blow the PUMP LINE back to the tank or visa versa.. with the lines still separated, start the engine and test to see if it stalls.. If it stays running you can pull the injector return line apart & look for the flex ring bits on #1 cyl and blow out.. Or put everything back together piece by piece and wait for it to shut off..