7275 injection pump question
- Thread starter jccuth
- Start date
DieselMonk
Platinum Member
- Joined
- Dec 9, 2004
- Messages
- 747
- Location
- Nova Scotia
- Tractor
- New Holland / T4.75 Powerstar & Boomer 1030, Case 580 SM II, Mahindra 1526
The pump may be air locked. There should be a "bleeder skrew" on the pump somewhere. It should be mentioned in your owners manual. It should be somewhere on the top (as air rises). As I recall, you have to give it full throttle, while engine is NOT running. make sure the fuel is turned on, then crack the line right before the injector pump until no more bubbles come out. Then you open up the injector pump bleeder screw and do the same. If it still doesn't start, crack the injector lines at the injector, one by one.
Thanks DieselMonk for the information. I think I have bled everything. There is bleed screw on top of the sediment bulb than as you follow the fuel line there is a bleed screw on top of the injector pump. I bled both of those points getting the air out. When I cracked the lines that exit the injector pump and crank the engine I get no fuel. The thing you said I may have done wrong was to crack one at a time. I`m not sure if I did one at a time or all 3 at the same time. I`m going to go back and re-bleed the lines and make sure I only crack one line out the injector at a time.
There is an inspection plate on the side of the pump and one on the side of the govoner. It allows me to see the pin on the selonoid moving back and forth. I can also see a wheel similar to a saw blade with out teeth in the govoner. It turns and there are 3 or 4 small blocks with a groove or hinge point that evidently cause the selonoid pin to move in and out. Anyway I am not a mechanic but I see no mechanical problem. I`m not certain where the valve is that opens and shuts allowing fuel out the injector pump. I believe it runs off a small intermitten electric charge from the selonoid.
I`m going to try bleeding the lines one more time to make sure I did it right.
I really like this tractor and have been working her hard. I have about 25 acres that has not been farmed in a couple years. I was plowing with a 2 bottom plow. I hope I get it figured out pretty soon even though I won`t plant beans until about the 1st. of May.
Thanks
There is an inspection plate on the side of the pump and one on the side of the govoner. It allows me to see the pin on the selonoid moving back and forth. I can also see a wheel similar to a saw blade with out teeth in the govoner. It turns and there are 3 or 4 small blocks with a groove or hinge point that evidently cause the selonoid pin to move in and out. Anyway I am not a mechanic but I see no mechanical problem. I`m not certain where the valve is that opens and shuts allowing fuel out the injector pump. I believe it runs off a small intermitten electric charge from the selonoid.
I`m going to try bleeding the lines one more time to make sure I did it right.
I really like this tractor and have been working her hard. I have about 25 acres that has not been farmed in a couple years. I was plowing with a 2 bottom plow. I hope I get it figured out pretty soon even though I won`t plant beans until about the 1st. of May.
Thanks
Great News!!!
I took the injector pump out of my tractor and bought it in the house to disassemble and clean. I learned that the valve that sends fuel out of the injector pump was sticking thats probably why the selonoid pin appeared to pulse because it could not push the pin that opens the valve up. I cleaned it good and lubed it with WD40. That must have been the problem. I put the tractor back together and found it now pumps fuel out the injector pump. When I tightened the lines it fired right up. I`m going to make sure I change the fuel filter on a regular basis. This problem taught me what a little dirt in the fuel can do.
Thanks for all the comments they really helped.
I took the injector pump out of my tractor and bought it in the house to disassemble and clean. I learned that the valve that sends fuel out of the injector pump was sticking thats probably why the selonoid pin appeared to pulse because it could not push the pin that opens the valve up. I cleaned it good and lubed it with WD40. That must have been the problem. I put the tractor back together and found it now pumps fuel out the injector pump. When I tightened the lines it fired right up. I`m going to make sure I change the fuel filter on a regular basis. This problem taught me what a little dirt in the fuel can do.
Thanks for all the comments they really helped.
7275
New member
I just had this happen to me and it did exactly the same thing and it is a jammed injector pump. $1293.00 for a new pump not including labor. Joys of owning a deisel tractor. 900 hrs when it happened to me. I am going to send it out to D&W injector service and see if it can be rebuilt.
Short Game
Veteran Member
The solenoid is for shutting off the fuel, not opening up the individual injector pumps' fuel meters. The loud clack when you shut off your key is the solenoid releasing its plunger to slam forward and block the governor from increasing the fuel supply. When you turn on the key, it pulls away from the rack gear that the governor pushes aft to increase the fuel through the three injector pump pistons.
I had an issue that could have been this same one with my 7274. In my opinion, that shutoff solenoid has too powerful of a return spring, and it slams that rack gear forward too hard when you shut off the key, and it can break a tooth off one of the three pinions, and that broken tooth can get stick in between the rack gear and the broken pinion. That rack gear rotates the metering rods in the three pumps via the three pinions.
I was able to take my pump apart and find the broken pinion. Being careful to not mix the parts from the three pumps, I replaced the broken pinion, which I got through a fuel injection specialty shop in Portland, OR. The pinion cost $7 and saved me the $1300 that I had found a pump selling for online.
With the broken tooth gotten out of the way, you could have only two of the pumps working at full capacity. The pinion with the missing tooth would only rotate the metering rod so far. The tractor would run again, but one cylinder could possibly be running lean. Mine would not run at all when the broken tooth was jamming the rack gear.
Though the guy at the fuel injection shop had never heard of this problem, I still live in fear of it happening again, every time I shut off the key and hear that loud clack!
All I did wrong was to turn off my key. It took me weeks with my tractor dead in my neighbor's front yard, cranking the engine for hours on end, and all my diesel expert friends standing there and scratching their heads along with me. It was not easy to work on with the loader in the way.
I know I'm late with this, but it might help someone else.
I had an issue that could have been this same one with my 7274. In my opinion, that shutoff solenoid has too powerful of a return spring, and it slams that rack gear forward too hard when you shut off the key, and it can break a tooth off one of the three pinions, and that broken tooth can get stick in between the rack gear and the broken pinion. That rack gear rotates the metering rods in the three pumps via the three pinions.
I was able to take my pump apart and find the broken pinion. Being careful to not mix the parts from the three pumps, I replaced the broken pinion, which I got through a fuel injection specialty shop in Portland, OR. The pinion cost $7 and saved me the $1300 that I had found a pump selling for online.
With the broken tooth gotten out of the way, you could have only two of the pumps working at full capacity. The pinion with the missing tooth would only rotate the metering rod so far. The tractor would run again, but one cylinder could possibly be running lean. Mine would not run at all when the broken tooth was jamming the rack gear.
Though the guy at the fuel injection shop had never heard of this problem, I still live in fear of it happening again, every time I shut off the key and hear that loud clack!
All I did wrong was to turn off my key. It took me weeks with my tractor dead in my neighbor's front yard, cranking the engine for hours on end, and all my diesel expert friends standing there and scratching their heads along with me. It was not easy to work on with the loader in the way.
I know I'm late with this, but it might help someone else.