8.3 isc p pump conversion thread

J

Jay_d

New member
Hello all, im Jay and this is my first post on this forum.
Im a logger from the state of georgia and have been searching cummins info on this site for years.

I have a tigercat feller buncher with a 215 horsepower isc 8.3 with caps fuel injection system. Yesterday, for the 3rd time my pump broke the gear pump coupling and so now its time to repair. Have bought multiple rebuilt units and cant get them to last much more than a year, so its time to retro fit a p7100 on this pig and hopefully be done.

I know the injector tubes can are custom and can be sourced through scheid diesel for less than $600.

I know the oem lift pump only runs 2 minutes at start up to prime the main pump and goes into bypass mode so im going to plumb in a holley blue electric between it and the fuel filter for supply fuel. I plan to just unplug the bypass pump and draw through it.

After that things get a sketchy. Im not sure if a p7100 numbered PES6P110A120RS7214 will have the same size shaft as the caps pump, but ive found a smoking deal on said pump. That pump is susposed to be a 250 hp pump and it worries me that this pump might not be tuned well for a wide open throttle all the time application. I also worry that it might run hot (water temp, or egts). The machine has a humongous radiator with a hydraulicly operated fan, but doesnt operate at highway speeds, air flow might not be as good.

Also a little unclear on the bracketry required to mount this pump. Do i reuse the isc brackets? Or order 6ct brackets from cummins?
 
You could just slide the fuel plate back to have the ppump make about the same "215" hp, what you time the pump will probably make more of a difference in heat and egt.
 
Jay_d said:
Hello all, im Jay and this is my first post on this forum.
Im a logger from the state of georgia and have been searching cummins info on this site for years.

I have a tigercat feller buncher with a 215 horsepower isc 8.3 with caps fuel injection system. Yesterday, for the 3rd time my pump broke the gear pump coupling and so now its time to repair. Have bought multiple rebuilt units and cant get them to last much more than a year, so its time to retro fit a p7100 on this pig and hopefully be done.

I know the injector tubes can are custom and can be sourced through scheid diesel for less than $600.

I know the oem lift pump only runs 2 minutes at start up to prime the main pump and goes into bypass mode so im going to plumb in a holley blue electric between it and the fuel filter for supply fuel. I plan to just unplug the bypass pump and draw through it.

After that things get a sketchy. Im not sure if a p7100 numbered PES6P110A120RS7214 will have the same size shaft as the caps pump, but ive found a smoking deal on said pump. That pump is susposed to be a 250 hp pump and it worries me that this pump might not be tuned well for a wide open throttle all the time application. I also worry that it might run hot (water temp, or egts). The machine has a humongous radiator with a hydraulicly operated fan, but doesnt operate at highway speeds, air flow might not be as good.

Also a little unclear on the bracketry required to mount this pump. Do i reuse the isc brackets? Or order 6ct brackets from cummins?
Click to expand...

Holley Blue isn't enough pump for a p7100.

The 250hp really won't run much hotter, and a "stationary" engine radiator will flow better than a road core anyway. That radiator isn't designed for road speed, and a road core isn't designed for sitting still.

As for the shaft, without having your p-pump here, I can't tell you. Also, a road truck governor will NOT work in a stationary high speed application. Been there, done that.

The brackets will not interchange, so you have to build your own.


I have multiple QSC's sitting here, and we have always been able to repair them and keep them running for way cheaper than a swap. I probably have about 400 QSC's running in combines at 285-310hp. I think I have a 250hp stationary engine pump here too off a C series.

Chris
 
Signature600 said:
Holley Blue isn't enough pump for a p7100.

The 250hp really won't run much hotter, and a "stationary" engine radiator will flow better than a road core anyway. That radiator isn't designed for road speed, and a road core isn't designed for sitting still.

As for the shaft, without having your p-pump here, I can't tell you. Also, a road truck governor will NOT work in a stationary high speed application. Been there, done that.

The brackets will not interchange, so you have to build your own.


I have multiple QSC's sitting here, and we have always been able to repair them and keep them running for way cheaper than a swap. I probably have about 400 QSC's running in combines at 285-310hp. I think I have a 250hp stationary engine pump here too off a C series.

Chris
Click to expand...

I wish mine was a qsc. They had real common rail. Mine is a isc and is a hodge podge of both.

Holley blue builds 20psi. Just how much supply psi does a 7100 use?

My application is stationary, its like a tractor, it runs wot during operation and loses rpms when the hydrayulic load pulls the engine down.
 
Jay_d said:
I wish mine was a qsc. They had real common rail. Mine is a isc and is a hodge podge of both.

Holley blue builds 20psi. Just how much supply psi does a 7100 use?

My application is stationary, its like a tractor, it runs wot during operation and loses rpms when the hydrayulic load pulls the engine down.
Click to expand...

30 to 40 psi fuel pressure is optimal.
 
Jay_d said:
I wish mine was a qsc. They had real common rail. Mine is a isc and is a hodge podge of both.

Holley blue builds 20psi. Just how much supply psi does a 7100 use?

My application is stationary, its like a tractor, it runs wot during operation and loses rpms when the hydrayulic load pulls the engine down.
Click to expand...

Our QSC's are not CR, CAPS pumps. QSC was the Industrial version of the on road ISC until they went to Tier 3 emissions in 2006-2007. ISC/QSC CAPS aren't terrible if you don't listen to mother Cummins on diagnosing them. They like to just replace the CAPS pump and charge about $6K.


25-40psi for a P7100, holley blue won't have crap for flow at 20psi. Need a better pump. My vote would be a mechanical pump, otherwise you're dumping one electronic wonder for an electric one that will die and leave you dead again.

I understand your application is stationary...hence why I gave the recommendation that your radiator should be fine.

Chris
 
Also, a 2 minute google search on that pump number you posted looks like it has an RQV governor...auto/truck governor...will SUCK for your application. It will turn all the RPM you could want, but will have no nuts to hold RPM once a load is applied.

You need an RSV governor...AG/Industrial...


The RQV/Auto governor will only govern at full RPM, 2500-3100 depending on which springs are in the pump...you can adjust the throttle stop screw to move it down, but that will back the fuel down as well. When a load hits an auto governor that isn't at WOT, it falls on it's face.

The RSV/Ag governor will hold a steady RPM, 1500, 1800, 2000, whatever you set the throttle at, doesn't matter, and try everything it can do with the fueling to keep it right there. The load can come or go, and it will try to stay steady.

You want RSV.
Chris
 
Thanks for the lesson on governors. Do you think somebody could swap out the governors pretty easy?

(I dont know much about p pumps)

Nevermind, looked into it. Now i feel stupid. For some reason i had it in my head that the afc was the governor.
 
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So i think i found another pump that will work better for my application
PES6A100D320/3RS2691 is the pump number and it uses a rsv governor. (And cost about half as much as a ps6.)

Do the a pumps have the right size tapered shaft to go in place of a caps injection pump. I know some use a 27mm nut and some use a 30mm nut. Mine is a 30mm

Is it that simple? If it uses a 30mm nut then the taper is cut right?
 
PES6A will have a smaller shaft than a PES6P. So your options would be to have a gear made/center changed...or find the P pump with a RSV governor.

Chris
 
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