ip problems

[Black dawg]

okay so a month ago I put a reman ip on my truck, trying to gain back some mpg, and fix an extended crank condition when cold. So truck then starts great, and mpg also better, but pump has problem with timing fluctuating at higher rpm. Pump shop gave me another pump under warranty that I am positive was the original pump that I took off in the first place. So put the pump on and mileage is still good, but I have an identical extended cranking condition when cold that I had in the first place. I am positive that air is not an issue, and have checked lift pump pressure. Glow system also functioning properly. Plugging in truck makes little difference and cranking speed is great. Am I wrong in thinking that the transfer pump could be weak and taking 6-7 sec to provide enough pressure in the pump? sorry this is so long and boring, but I am getting a little frustrated . the pump that started good was on for 2 weeks and truck started great with it every morning.

 

[Black dawg]

forgot to mention that when truck starts after 7-8 sec of cranking it fires clean. there is no missing or unstable idle. it also seems to rattle less for the first few sec of running and then slowly gets to normal

 

[OkieGringo]

Check to be SURE all the wiring connectors to the IP are in the correct order. Do you know correct order? It is VERY important. I have an electric transfer pump on my engine and even if I forget to turn it on or if it accidentally gets turned off, the engine will run for about 5 miles on just the fuel in the line before the IP. I had a leak down/air problem that I chased for 3 yrs to no avail. Then I changed the fuel filter and cranked the filter tight with a filter wrench just for the hell of it. No more problems with air leak. Nimodo? OkieGringo

 

[Black dawg]

Okie, thanks for the suggestions, and yes wiring is correct and connections are good. At this point im wondering if the shutoff solonoid is weak and with the lowered voltage from gp operation and starter draw, it takes longer for it to work properly. also how did having your electric pump affect your drainback issue and cold starting. just wondering if it being on the amount of time the plugs were on was enough to reprime.

 

[OkieGringo]

BW, the e-pump helped a lot to get it started and I needed to abuse the starter a little. But the filter NOT being tight was the problem for me. You MUST have a air leak somewhere. When was the last time you replaced your filter? Maybe not enough fuel getting thru it. Try getting a bottle/bucket of fuel under truck and run a line up to the lift pump. Remove all the GPs to make it easier on starter/batteries then bleed the lines. Get/make a remote starter switch and jumper a wire from Batt + to IP FSS. Comprende? OkieGringo

 

[Black dawg]

Okie, I have put clear hose at the filter return line and also at the return from the pump, there is no drain back taking place. The tuck isnt hard to start, it just cranks longer than it should (6-8 sec) and then starts cleanly. it did not do this with the last pump, it started very quickly like 2 sec or so. timing is set to spec along with cold and hot idle speeds, and cold advance is functioning. I get the impression from the pump rebuilder that they tink my truck is just old and worn out and that this is acceptable. My truck is far from tired and I just want it to work. I havent tried putting hot wire to fsv, never feel like messing with truck before going to work.

 

[IDIeselman]

Did the rebuilder give you a NEW check valve when you got your old rebuilt pump back? just a guess but I believe if the check valve at the fuel inlet on the pump is bad you will have some fuel draining back.
Tim