M1009 fuel pump

[jimm1009]

I went on line last night to one of those web sites that has a GM mechanic
that is available for questions.

I was told that the engine driven fuel pump is supposed to have 7 to 11 PSI output @ idle.
Does anyone know if this is true?
I can't find a reference for that in the -34 TM or in the Chevy factory manual
so I am not sure.
I am troubleshooting white smoke with a properly timed injection pump and new filter. I had much more smoke before I change the filter but still have some and the pressure being too low will also cause white smoke but I can not find the reference for minimum pressure into the intake line for the injection pump.
I have 4 PSI @ idle with some white smoke. The pressure actually drops from idle to about 2 PSI @ around 1200 RPMs estimated.

As a side question, has anyone opted for an auxiliary electric pump and has this helped your CUCV? If so, do you still have info on the pump?

Jim

 

[Ken_86gt]

From the TM:
Step 6. Check fuel pump operation. Disconnect input fuel line at the fuel filter. Disconnect
pink lead from fuel injector pump. Use a quart capacity container, and crank
engine for 15 seconds. Container should be at least ¼ full or contain ½ pt (0.231)
of fuel. Install low pressure gage in fuel line. Crank engine for 15 more seconds.
Fuel pressure should be 5.5-6.5 psi (38-45 kPa). Reconnect fuel inlet line to fuel
filter, and reconnect pink lead to fuel injector pump.
If fuel flow is insufficient, replace fuel pump. (See paragraph 3-10)

The reality is that you can frequently run the truck without a lift pump at all- the injector pump will suck fuel just fine without it. But you will also suck air if there are any leaks.

 

[Blue2actual]

I installed Buy Mr. Gasket Electric Fuel Pump Diesel 12D at Advance Auto Parts and it hasn't failed me yet. It's pushes 7 PSI and works perfectly on my 1009. The reviews aren't great on the web site but mine has lasted for 18+ months with no issue. I ran new lines to the tank, parallel to the stock lines just in case the pump were to fail. If it fails, I will just disconnect the electric pump lines and pop on the stock lines and continue mission.

*edit* The pump is mounted on the frame rail just behind the alternators. It only runs when the ignition is on.

 

[GPrez]

I installed Buy Mr. Gasket Electric Fuel Pump Diesel 12D at Advance Auto Parts and it hasn't failed me yet. It's pushes 7 PSI and works perfectly on my 1009. The reviews aren't great on the web site but mine has lasted for 18+ months with no issue. I ran new lines to the tank, parallel to the stock lines just in case the pump were to fail. If it fails, I will just disconnect the electric pump lines and pop on the stock lines and continue mission.

*edit* The pump is mounted on the frame rail just behind the alternators. It only runs when the ignition is on.

+1. I have been using the same electric pump on mine for 2-years and no issues. Not sure why the people who leave those reviews were having trouble. When my mechanical pump stopped working I bought a replacement, but it wouldn't pump fuel either. I think the lobe that operates the ear on the mechanical pump wore down.

 

[isaacucv]

I installed one from a 1990 Chevy with a 6.2. So far so good. I installed it on the frame where the rubber fuel line is. I just took the cover plate off and removed the stock 3/8 rubber line and plumbed the pump with a filter right there. It works great and saves all the cranking on the starter when trying to prime the system. I was in the same boat, I replaced my mechanical pump and it wouldn't pump fuel. I also did the spin on fuel filter mod, it was easy and more reliable.

 

[ADKM1009]

For those that have done this, where/how did you get the keyed power for the positive wire? Also, what fittings do I need to connect/couple the fuel line where the old mechanical fuel pump is once I remove it and replace it with a blanking plate? Thanks. Not where mine is right now and I need to order everything in one go. It is up in the Adirondacks and dashing out to the parts store isn’t super easy up here, so I try to order everything I need for any given project in advance.

 

[MarcusOReallyus]

Hey, let's not hijack the OP's thread. This is about the correct output for the stock pump.

jimm, just within the last week or two I read a post from cucvrus (The Grandmaster of CUCVs) and he pointed out that there is a pump that is physically compatible but will not supply enough fuel because the actuator arm is wrong.

If you can find that post it might answer your question.

 

[ADKM1009]

Pretty sure eight years on the OP has their answer.....

 

[frank8003]

Pretty sure eight years on the OP has their answer.....

Yeah, but I like it anyhow. Eight years or 30 years... it passed all so quick I need to be reminded of stuff.