TPIJeep

I have a Bosch external pump on my Jeep with a TPI conversion... the pump seems to be vapor locking after say an hour or so of slow running. If you let is sit for a while and it cools you can hear it reprime itself and it will run for a while..... To say the least I am sick of it and need a new pump that is a little more heavy duty.. Any suggestions? I am looking at a Mallory Comp Pump Series 60FI, flows 60 GPH and 75 psi max. Would this be a good pump or is there something that would work better?

Thanks for your help I am in a bit of a rush on this one...

BlazinOR

Well I run a Bosch external pump on my Blazer too.........and no problems. Big question - do you have a return fuel line? Gotta have that. Otherwise, is the pump back near the pump? Below or above or even with it? MIght be sucking too hard. Could be the sock over the pickup.

More info needed.

------------------
'79K5 Blazer with 406TPI

mtccl

Vaporlock is most often due to line location and associated heat. Check the routing and shield with temp-tape if possible. Also try shielding or wrapping the pump. I had to shroud one with aluminum flashing once to stop vaporlock.

------------------
87 TA, 305 TPI, Custom CAI, K&N, ACCEL 8mm wires,ACCEL Super-coil, ACCEL Plugs, JET TPI Airfoil, Cherry Bomb Muffler, 160* thermostat
The Phoenix Project..click to see my project car
Trans Am stuff and GIRLS, GIRLS, GIRLS!!!!!

TPIJeep

I thought this might be the problem because the pump was fairly close to one of the mufflers... I then moved the pump and lines totally away from the exhaust and I still have the same problem....

Do you all have any experience with the Mallory pumps or any that might be better, I need to get this taken care of before Saturday...

Thanks

Iroc-cj

TPIJeep
I had the same problem on my CJ-7. tried wrapping the pump, didnt help. ended up going with a in-tank pump. nothing worse than being stalled on the trail with EFI problems. carb guy's love to rub it in.
Did you get your prom dialed in?

TPIJeep

The PROM is okay.. had to change head gaskets and get the cyl psi down to 190 from 240... now the ping is gone but the headers are still glowing...

What pump did you use to put in your tank... any mods necessary to the tank? I am in a big hurry on this one any help would be appreciated..

Iroc-cj

TPIJeep

I found a stock TPI pump & tank at a junk yard for $40.00, cut the lock ring assembly off the tank, made a gasket, cut a hole in the top of my stock cj-7 poly tank & pop riveted it on. i had to bend the fuel lines at the pump to make it work.
I have not had a problem since, but i keep the frame mounted fuel pump in the jeep as a spare just in case
I've seen your jeep pics on the POR bbs & i'm jealous!!!!

good luck

BlazinOR

Not arguing with anyone here, but there is NO reason you can't run an external pump. My builder is a TPI fanatic, has done over 130 conversions, and EVERY one is running an external pump..........with no problems. Most are Bosch pumps for a Jaguar (as is mine). These conversions range from Jags to s-10 pickups to Blazers to 1/2 ton pickups.

Do you have a return line active?

------------------
'79K5 Blazer with 406TPI

Iroc-cj

BlazinOR

you are right, there should be no reason, thats why i bought the external pump. The instructions say to mount the pump below the fuel tank, on jeeps this is not possible without getting it ripped off by a rock or log. I think you might be right about the sock or stock sender assembly's 3/8" fuel line. BTW i have a 3/8" return line.

TPIJeep

Thanks for the responses, I ordered the Mallory pump and with its design I will be able to mount the intake and outlet fittings even or below the bottom of the tank... I will shield the pump and lines from the exhaust pipes. Then I will run the lines through the frame and come out even with the fuel rail fittings... Hopefully the pump will run easier and will not loose prime when parked due to the lower mounting and hopefully the frame will help keep some of the heat off the lines... I will keep yall posted..

Thanks...