Bad injection pump?

[Randybee1]

Hey guys, I have a friend with a B275 Tractor. He bought it a while ago. It had been setting for quite some time. Following the procedure in the manual for bleeding the system there are 2 bleed screws. The lower bleed screw squirts out a nice stream of diesel while cranking but the upper bleed screw barely trickles anything at all. Any ideas? Bad injection pump? Could the timing be off? I'm thinking maybe someone took the pump off and put it on wrong. There are directions for setting the timing when replacing the pump but I have not looked at that.

The pump is a C.A.V. pump

I'll go read the  "how to post pictures" and come back in a bit with a few pics.

Thanks,
Randy B

[mike90045]

I've heard ATF was a safe soak if you are taking it off.

[vdubnut62]

Hello Randy, I have lived with an old B-275 with the BD144E diesel engine for the last 25+ years. The one you pictured looks to be a later model (as is mine) with the CAV pump.
Earlier models have a weird inline pump with a pneumatic governor.  They are very strong for their size and pretty dependable once you learn your way around them. I pull a 6 foot tiller with mine, and it handles it just fine.
Bleed the fuel filter first! Then when you have all the air out of it, wait 5 minutes and bleed the air out again. Loosen the fuel line at the pump and bleed it there. You should get a lot of fuel there.
Check the fuel line strainer! The line that goes into the back of the pump has a VERY fine strainer 'way down in there under it. Remove the line, then remove the fitting the line screws into. Keep removing fittings until you reach the strainer. Carb cleaner and compressed air works nicely to clean it. DO NOT THROW IT AWAY!! It is the last line of defense against 50+ years worth of crud and rust.  I once nearly pulled all my hair out over that strainer getting clogged, like to have never found it.
Yes, check the timing! It's pretty straight forward, align the marks on the gears and align a mark under a plate on the pump. When I rebuilt the engine years ago mine had some gear wear so I advanced the pump as far as it would go after I timed it.
Mine is a Royal B!t#H to bleed the air out of!!! I actually avoid changing fuel filters because of it. Bleed, bleed, bleed, tie another tractor to it, pull it off, it will run a while and die,
bleed, bleed, bleed, pull it off and repeat till it will continue to run. I'm not kidding. I have never seen anything like it in my 50 plus years.
The pump on mine has probably 7000 plus hours on it, so that might be a contributing factor.
Patience and Perseverance will triumph eventually.
Ron.

[Randybee1]

Ron, Thanks for the info! It is very helpful!!!!!  I'll pass this on to my friend.
Randy

[vdubnut62]

Glad I could be of some help. Best I remember, lots of fuel at the bottom screw and not so much at the top is normal.
After it is all bled out the best you can, loosen the lines at the injectors and let it work the air out there.
I usually pull mine off with another tractor instead of trying to crank it with the starter. The Lucas positive ground starter is pretty weak and won't take a lot of hard cranking from bleeding the system. If needed I can get new, not rebuilt ones for $115-$125 or so from a guy locally.
I changed mine over to  negative ground with a Delco 10si alternator years ago. ( the starter doesn't care if it is positive or negative ground, it works just the same)
Ron.

[Randybee1]

Gonna give it a shot this weekend.