killed ANOTHER pump with too much fuel pressure
05-06-2007, 11:16 AM
#16
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fwiw the bosch tech I spoke to said the seal should be good for pressures well over what I am running and he had never heard of poping one. my truck was a test bed for higher pressure on the delivery side, the firs couple times we could not be sure it was the seal and not just a defective seal....the seal is obviously good for somewhere between 20-30psi tops for extended use. I will pull the pump tomarrow and verify that I did not puke an injector.....I am 99% sure it is the problem seal again.
05-06-2007, 08:05 PM
#18
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"This is for a 24 V with the VP-44. 30 PSI is perfect for performance. We have another system as well, but the pressure is typically only 22 PSI at WOT and around 6 at idle. Most guys opt for the 30 PSI system. The only difference is the supply pump we supply.
The 30 PSI system is the best route, IMO. Back when the 12 V mechanical pump started being installed in the 24 V with the VP-44 pumps, people were seeing around 55 PSI on average. Even at idle it could be as high as 50. That was years ago and no reports of failures were reported from this pressure. Remember the internal feed/suction vane pump inside the VP44 is raising the pressure over this value to the plungers. Anything you can do to increase pressure to vane pump is a good thing. To a point of course.
Back when things were getting going hard we tested, on the dyno, many pressures that made the best HP for the 24 VP44 engines. 22 PSI and up was the best, with no more or less power made at 50 up to 72 PSI. At 72 and up we lost a few. Probably from cavitational losses.
Don~"
The 30 PSI system is the best route, IMO. Back when the 12 V mechanical pump started being installed in the 24 V with the VP-44 pumps, people were seeing around 55 PSI on average. Even at idle it could be as high as 50. That was years ago and no reports of failures were reported from this pressure. Remember the internal feed/suction vane pump inside the VP44 is raising the pressure over this value to the plungers. Anything you can do to increase pressure to vane pump is a good thing. To a point of course.
Back when things were getting going hard we tested, on the dyno, many pressures that made the best HP for the 24 VP44 engines. 22 PSI and up was the best, with no more or less power made at 50 up to 72 PSI. At 72 and up we lost a few. Probably from cavitational losses.
Don~"
05-06-2007, 08:17 PM
#19
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05-06-2007, 11:05 PM
#21
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38 at idle and up to 50 at cruise. I'm planning on putting a regulator on there soon. Wicked Diesel has a kit which will ramp up fp with boost that I've had my eye on.
05-06-2007, 11:57 PM
#22
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I used to be the original proponent for big fuel pressure. anymore, heck it is begining to be a crap shoot. I will tear it down tomarrow and post the scoop. I will be bummed if it is another pinhole in that "bulletproof" seal.
05-07-2007, 09:37 AM
#24
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It does run on so many other things so hopefully the ULSD stuff won't kill em.
05-07-2007, 09:55 AM
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05-07-2007, 02:48 PM
#26
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update!
the seal did pop again. thankfully my pump hero did not charge me a penny. he said he is seeing a few more of the seals poping now that people are running bigger pressures. he swears that the seal can take a bunch of pressure. well I pulled my lp and fired my pusher only.....stuck my 30lb guage to the point I could not pull it down even with the comp. I bought it as a 7lb pump, it is putting out well over 30lbs. oddly when new, it, combined with my stock pump, made 22psi. the pusher over time has developed an increase in pressure to at least 5x what it is supposed to make. interesting that some pumps lose pressure and mine did the dead opposite....oh well. so long story short, the limit to the seal is around 40-50lbs in our trucks that have puked them.
the seal did pop again. thankfully my pump hero did not charge me a penny. he said he is seeing a few more of the seals poping now that people are running bigger pressures. he swears that the seal can take a bunch of pressure. well I pulled my lp and fired my pusher only.....stuck my 30lb guage to the point I could not pull it down even with the comp. I bought it as a 7lb pump, it is putting out well over 30lbs. oddly when new, it, combined with my stock pump, made 22psi. the pusher over time has developed an increase in pressure to at least 5x what it is supposed to make. interesting that some pumps lose pressure and mine did the dead opposite....oh well. so long story short, the limit to the seal is around 40-50lbs in our trucks that have puked them.
05-07-2007, 04:12 PM
#28
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I asked my pump guy about the ulsd and the 7100.....he said well, the p pump is doing better then the rotarys are, but pretty much all the older pumps are gonna leak....and pertty bad. it is only gonna get worse. he was kinda happy cause he is burried in work.
