Strange 150# inj failures..

[Chuck Leeper]

Just completed a preliminary flow test on a set of Bosch gray tops...As the bench pressure came up to 45psi, 5 of the 8 injs started leaking at the joint where the plastic top is sealed to the metal case. 1 was so bad, that flow fluid filled the plug socket!

This is the second set I have seen do this. The first set had 7 of 8 leak.

All 16 injs had been run on methanol, in hi hp outlaw cars. [At very hi fuel pressures, hi boost].

I've not been able to disassemble an inj, as the customer took them with him.
My suspicions:
1. Hi op pressures are exceeding the seals ability to hold.
2. Methanol is degrading the seal.

NE1 have this problem??? Could be fatal, should a fire occur...

The REALLY SCARY part: Neither customer was aware of the leaks....

 

[JOHNDEEREGN]

Chuck are the seals EPDM (regular rubber) or Viton? I would think for Meth they should be Viton?

 

[Mike Licht]

I just had a customer who had this problem with that injector on an E85 street car. 1 injector our of 8 and I just dismissed it to being defective or abuse. I need to take a better lok at the other 7 thanks for the info
Mike

 

[Chuck Leeper]

Chuck are the seals EPDM (regular rubber) or Viton? I would think for Meth they should be Viton?

Ty, the leaks are not on the o'rings... These are leaking thru the joint where the inj is put together....

 

[JOHNDEEREGN]

Ty, the leaks are not on the o'rings... These are leaking thru the joint where the inj is put together....

Back under my rock :biggrin:

 

[Chuck Leeper]

I just had a customer who had this problem with that injector on an E85 street car. 1 injector our of 8 and I just dismissed it to being defective or abuse. I need to take a better lok at the other 7 thanks for the info
Mike

Mike, can you chuck the defective one up, and take it apart??......

 

[Dusty Bradford]

I agree it may be the operating pressures. I try to keep my base at 45 but lots of guys are running over 70 base with 40-50# of boost. I've always wanted enough injector to keep the pressures down. I've heard of some running over 100# base.

 

[Chuck Leeper]

I agree it may be the operating pressures. I try to keep my base at 45 but lots of guys are running over 70 base with 40-50# of boost. I've always wanted enough injector to keep the pressures down. I've heard of some running over 100# base.

Dusty, the cars are some that Brad Brand works on. He uses really high Fp on his car, and I'm betting the same is being done on these 2 cars..AIRC, he uses 75psi as base fuel psi.

 

[RmvBfrFlght]

The leak is from the internal O-ring that seals the plastic top to the metal body. There are some other 1st gen Bosch injectors that also have this problem, even at normal fuel pressures. With the high fuel pressure probably better off with the EV6 style injector that is all one piece.

RemoveBeforeFlight

 

[Dusty Bradford]

Billet Atomizer's

I'm a dealer for these and extremely happy with them.