We have a Case IH 7220 magnum tractor that is not making the power it should. It has a cummins 8.3 L engine. I'm looking for information on the Bosch injector pump....first bit of the part number is RSV500 1100MW if that helps. The tractor does not smoke so I think it's starving for fuel. Once this problem is figured out I'd like to turn the pump up a little...30-40HP or so and still be safe with EGT's...it is a tractor after all and generally runs right on the pin all day.

Things I've done:

Checked the boost reference lines for loose fittings/cracks. None found
New lift pump installed. No difference
new fuel filters. No difference
pulled fuel line from lift pump (coming from the tank) and the line ran like there were no restrictions...but it is a rubber line and may be pinching off when the tractor is running....my next move is to replace this.
Fuel filter mount has been taken all apart and completely cleaned out...nothing was found dirty or plugged so this made no difference.

Things I have not checked or had a chance to try yet:

See if the wastegate is sticking (causing the turbo NOT to build boost)
check boost pressure under load
check fuel pressure under load (from the lift pump)


This old girl is supposed to be a 150 hp tractor...she sure doesn't act like it right now. Anyone know if this pump is similar to the "P-pump" that's on the older 12 valve cummins?

Did you change the inline fuel filter.

What are you comparing it to??? We have one also and it doesn't seem to have the power that our 7120 does, but the 7120 has had the screw put to it some. The 7220 was the first emission engine and it ran lower rpm's and didn't seem to pull as well on the highway imo. Our was really sick at first and we found that one on the intake top plate bolts were loose, which was allowing it not to build as much boost as it should. Then we also found that the pump was wore some and had it rebuilt. Those two things helped a lot, now it pulls like it should, 32.5' field cultivator at 6-8 mph. How many hours are on the tractor??? Maybe the pump is wore out, those pumps will generally only run so many gallons of fuel and then need to be rebuilt, or maybe you got some bad fuel and it wore it out prematurely.

Check the overflow valve. Its the fitting going back to the tank. Remove it and shake it, it shouldnt "rattle"..if it does its broke.. or just hook-up a pressure guage to the inlet/outlet..should be above 20psi...
The #'s you gave were the govenor #'s..look on the side of the pump where it mounts-up. Should have a 10 digit #.. starting w/ a, 0 or 9... if I can get those #'s I'd be glad to help.

I forgot to mention the overflow valve was also replaced. We have about 5500 hours on the tractor. I installed a boost gage and a fuel pressure gage a couple days ago and while I was doing that I found the fitting going to the wastegate was blown out and wouldn't tighten properly (couldn't tell until you put a wrench on it). The way the plumbing is, evidently that leak was enough to reduce the pressure in the line going to the aneroid (the anti smoke device on the fuel pump). So, just for kicks I unhooked the wastegate line and plugged the opening and that fixed the problem. Dad is talking about turning it down just a bit so we don't start breaking things....My brother was the first to test it in the field and he said you couldn't work it with the 5 bottom plow he had behind it....it would pull that thing as fast as you could stand to drive acorss the field and still had power left over, (I guess he got up to 8 or 9mph on the radar speedo in the tractor).

So from what I can figure the aneroid wasn't getting the proper boost signal and wasn't allowing the injector pump to put the right amount of fuel in. Anyways, the problem is fixed...thanks to all that replied. In case anyone was wondering fuel pressure runs between 23 and 25 psi and with the wastegate unhooked the turbo pushes about 27 psi of boost. I feel relatively safe running this much boost because exhaust temp is fine and the bigger tractors in the series run up to 24 psi stock. So I'm thinking it's tuned to be a 7240...now we just need the stickers.

I also found another interesting tidbit about the difference between the 7120 and the 7220 by comparing the nebraska tractor test data.....the 7220 has 16.5:1 compression with about 18 psi boost stock and the 7120 has 17.3:1 compression with only about 10.5 psi of boost. But they both make max torque at 1400 RPM.

Hunting: I couldn't find an inline filter. There are two spin on filters after the lift pump....

Brian, I was comparing it to itself...last fall it would pull the harrow faster and we have a 5200 gallon manure tanker....the tractor always seemed to have adequate power to run that in the past but this spring it would fall on its face when we flipped the PTO on. We have a 7120 too...and that thing with 10000 hours on it would walk circles around the 7220 this spring and that wasn't the case before. Our 7220 runs slightly higher RPM's than the 7120.....we did get the 7220 used so maybe someone has been into the pump already... 7120 is maxed out around 2250 RPM and the 7220 is about 2350 RPM or so.

Pump Guy, if anything else comes up I might take you up on your offer.

The wastegate problem is common about that many hours. There should not be a problem running at least 200+ hp out of that tractor. The inline fuel filter mentioned by another poster is directly behing the left hand hood side panel that pulls out. It can be one of two styles. Either it has hose barb style ends that the fuel line hose slides over and is held in place by hose clamps or it has threaded fittings that use fuel line with ferrels and compression nuts that tighten up to the fuel filter. It is before the other two fuel filters mounted to the fuel filter base. I think the filter sells for about $15-$20 at your local dealership. It should sit behind the engine oil filler neck and oil dipstick location. Good luck.

Our 7230 had an in line filter. It was behind the steps and to the left. Dont know if your tractor has it but i know our tractor did.

Yeah our 7220 has the inline filter right there by the two spin on filters before the lift pump. If yours doesn't, I'd put one on there to help catch some of the big stuff.

And our 7120 runs out at 2400 rpm (great for roading) and the 7220 runs out at 2250 (just a little above pto speed, sucks on the road).

Our 7120 will still run better than the 7220, but we have had the 71 since new and the 72 we bought used with 2700 hrs supposedly. After we had it into the dealer b/c of no power they did a search on the sn and found out that it was sold in NC new and had the dash replaced under warranty with 3500 hrs back in 98. We had the pump sent off and rebuilt and put back to factory last spring, it came with a 1 yr warranty, so we haven't done anything to it yet. They did stick it on the dyno and it pulled around 170 hp at the pto, so I am guessing that our 71 has around 200 hp.

How much does it smoke?? Have you had a chance to work it yet and see if the EGT's go up??

Sorry I haven't posted lately...we have had a chance to work it and it smokes VERY little, but has all kinds of power...more than anything else we've ever had. You really have to try to make it work. According to the factory gage, EGT's are good...about half way up when working it, right where they should be. I don't know what temp that matches up with, but they aren't any hotter than before. I'll double check for the inline filter, but I didn't see one in around there...I checked that whole fuel line to make sure it wasn't pinched somewhere....I'm betting someone took it out when they had trouble before we got it and I'll wind up putting one back in.

Brian - We're in the same boat...had the 7120 since new and that is still a good running machine with 10,000 hours on it...haven't even rebuilt the injector pump yet (knock on wood). We got the 7220 used with about 2500 hours on it (I can't remember exactly) and that one has been OK for the most part but some of the controls seem a little wierd compared to the 7120....like the throttle doesn't go all the way forward and feels like it moves too easy...and some other little quirks, but nothing too serious. How much did you turn the screw on the 7120? Does that one smoke? My old man was pretty impressed with how the 7220 acts now and wants to do the same thing to the 7120.

Hopefully The Pump Guy will check in or someone else who knows about the older bosch rotary pumps...I'd like to do some learning about those pumps (like on our old 1066 and 5088) just to do a little tuning on a couple of our other tractors. I can get part numbers later if I need to.

Thanks to everyone for the pointers!

How can I be of assistance...All I need are some Pump #..