Pump & timing question

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I have about 120k on ole '97. It still feels like a new truck, & runs faster than I can think. I have always thought it was properly set up & timed from the factory, and have no reason to believe timing has changed. But, I was wondering about pump cam lobe wear over time, and if timing would be affected by worn & "shorter" cam lobes. How many miles would it take for the lobes to wear in the pump before it affected lift and/or timing? Is this something to be expected during normal wear & tear, and is this one of the reasons timing slowly gets retarded?

 

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I wouldn't think this would be a problem but I'm not a p7100 mechanic. #2 diesel fuel is a lubricant, but Piers or another Bosch pump expert would be able to spill the beans. IMO if it runs good, you need more power! Just kidding. If it runs good, it runs good. Know what I mean Vern?

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J Case
'95 2500 4x4 Auto Reg Cab
Big Dick's 2inch lift
BD tc, vb, Pressure lock, and 4" exhaust.
K&N RE-0880 with 25-0880 prefilter
Custom Fuel Pump by Piers!!

POWERCHOKES BEWARE!!!!!

 

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The governor and the bottom end of the P7100 are lubricated by engine oil. The camshaft and "roller lifters" are in the bottom. With rollers, wear whould be virtually nil if you change your oil at reasonable intervals.

 

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Dennis, About a year after I bought my 98 I stopped by A&M Turbo in Macon, GA to pick up some "stuff" and one of the pump guys started talking to me about my truck. He let me know that a TSB of sorts had come out from Bosch about internal pump timing. He showed me the bulletin and I decided to have the work done. They pulled the pump tested and timed it then reinstalled it and timed it back to the engine. The truck wasn't a rocket because of that but I could tell a difference and my mileage increased about 1 mpg with no load. It wasn't a wear problem. Those guys said the pump should probably outlast the engine but recommended a "tune up" about every two to three years.

 

[Archive]

I,too, was interested in verifying the timing on my not so new '94. So, at 70,000 miles the pump was removed by a highly competent shop in the Northwest. Like most P7100's, the timing was about a degree and a half off (retarded). Advanced it to 14. 5 degrees btdc. Yes, there is a difference in performance.
Just as importantly, I had them check clearances on the pump to see how much wear had occured. Tolerances were found to be better than new. As Joe D. says, P7100's are lubricated by oil, not by fuel which is why they are so superior to the pumps on ISB's. Estimated service life is one MILLION miles. Keep the engine oil clean and you can forget about wear.

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'94 SLT 2WD, 5 Spd. , TST #6(250/635), 215 HP Injectors, Calibrated Pump, 14. 5 cm2 Turbo, ATS Exhaust Manifold, 3. 54, all Synthetics, By-Pass Filtration, EGT & Boost Gauges, Psychotty Air System, 4 " exhaust, BD Exhaust Brake, Horton Fan, Prime-Loc, Cummins Chrome Kit, Homeless Cat, Air Lifts, Rancho RS9000's, PIAA's, 255x85Rx16's and copious amounts of 12v Pride.