5521 Injection pump question/s

[joe bleaux]

I bought an injection pump from a 2000 6.5td. It is a 5521 and has ~ 60k miles on it but it was pulled and sold to me because the fuel rate at idle is 3.0mm. Could someone comment on what other problems could cause this besides a fuel solenoid failure of some sort or clogged filters or bad lift pump?

Thank you.

Joe

[JohnC]

I don't understand what you mean by "the fuel rate at idle was 3.0mm"

IIRC, the fuelk rate at idle is around 7 or 8. If it was 3, it wouldn't be running very fast....

For that matter, I don't know why anyone would even look at the idle fuel rate unless they were chasing some other problem.

[joe bleaux]

JohnC,

Unfortunately, I don't know what 3mm fuel rate means, either. I would venture a wag if it were 3milliliters but then one would have to have the time period.

That is what the stealership told the prior owner of the pump. It set no codes. I don't yet know what other problems were being chased-down. I will try to find out.

Thanks for the reply.

Joe



I don't understand what you mean by "the fuel rate at idle was 3.0mm"

IIRC, the fuelk rate at idle is around 7 or 8. If it was 3, it wouldn't be running very fast....

For that matter, I don't know why anyone would even look at the idle fuel rate unless they were chasing some other problem.

[DmaxMaverick]

3 mm of fuel means 3 cubic millimeters of fuel, per 2 crank rotations, or 8 combustion events (fuel injections). It may be worth having it tested by a Stanadyne repair shop and verify this, as it doesn't sound right. The PCM will command a "desired" fuel rate/RPM, and the pump will return an actual. If they can't meet, then the pump is shot. However, if it was tested on an engine, I don't see how this can happen, because I don't think the engine will run with that little fuel. At any rate, it may be repairable, and may not cost much. Could just be a calibration issue. You'll have to get the Stanadyne test results and have the tech tell you what is right or wrong with the pump. 60K miles on the pump isn't very much at all.

[joed]

I remember reading something on the other 'site' about some guys doing an 'optic bump' to the optical encoder on top on of the IP that would result in a lower fuel rate on a scanner. The encoder plate was shifted slightly affecting the reading of the cam ring, I think? It was supposed to make the throttle more sensitive.

Maybe this was done or just set that way when the pump was manufactured?

Joe.

[joe bleaux]

Okay, Joe and thanks for that info. I will go over there and see what I can dig up.

Joe


I remember reading something on the other 'site' about some guys doing an 'optic bump' to the optical encoder on top on of the IP that would result in a lower fuel rate on a scanner. The encoder plate was shifted slightly affecting the reading of the cam ring, I think? It was supposed to make the throttle more sensitive.

Maybe this was done or just set that way when the pump was manufactured?

Joe.

[joe bleaux]

Dmax,

I have sent a pm to you.

Joe


3 mm of fuel means 3 cubic millimeters of fuel, per 2 crank rotations, or 8 combustion events (fuel injections). It may be worth having it tested by a Stanadyne repair shop and verify this, as it doesn't sound right. The PCM will command a "desired" fuel rate/RPM, and the pump will return an actual. If they can't meet, then the pump is shot. However, if it was tested on an engine, I don't see how this can happen, because I don't think the engine will run with that little fuel. At any rate, it may be repairable, and may not cost much. Could just be a calibration issue. You'll have to get the Stanadyne test results and have the tech tell you what is right or wrong with the pump. 60K miles on the pump isn't very much at all.