Diesel Place banner

1 - 13 of 13 Posts

·
Registered
Joined
·
55 Posts
Discussion Starter #1
This question is for the guys running the stock lift pump. Can you hear it running when the engine is running? I think mine is not working properly. I keep forgetting to bring my DVOM home from work to check for power. I installed leroys lift pump harness this weekend with the WTS option. When the glow plugs are getting power I can hear it running but with the engine running I can't. I'm trying to replace the OPS due to it possibly being bad. And with the reputation they have I figured it wont hurt. Apparently superman or steroid stan installed the nuts holding the glow plug relay to the intake and with what I have at home i couldn't break them loose.
 

·
Registered
Joined
·
5,514 Posts
I would say in general I don't hear the lift pump with the engine running. Maybe after the engine is warmed up and less clacky and I'm on hard pavement vs grass and I am listening for it maybe.



Different pumps make different levels of noise depending on the pressures they are working with so that could effect the sound. I just changed mine yesterday and the old one was kinda noisy all the time except for when I think it was maybe stuck. The new one is almost silent once it builds pressure and the engine not running.



I would think you will be in good shape with that harness and a new sensor.
 

·
Registered
Joined
·
55 Posts
Discussion Starter #3
Ok I was thinking that after it had primed the line so to say it shouldn't be heard much. Im hoping that I can get my sensor swapped tomorrow for piece of mind. And im hoping that it is bad or intermittently working and is what is causing my what seems to be a missfire feeling when under half to heavy throttle.
 

·
Registered
1995 GMC Suburban
Joined
·
17,730 Posts
Just make sure the OPS is ACDelco and not store brand aftermarket.

What you describe is normal.
You need to test it when engine is running, you can direct the hose of the t-valve into a bottle and open the t-valve.
If fuel is flowing out, then you are good.
You should get about 1L per minute.
 

·
Registered
Joined
·
55 Posts
Discussion Starter #5
Just make sure the OPS is ACDelco and not store brand aftermarket.

What you describe is normal.
You need to test it when engine is running, you can direct the hose of the t-valve into a bottle and open the t-valve.
If fuel is flowing out, then you are good.
You should get about 1L per minute.
Finally got it changed and i used a ac delco. Took longer then I wanted but having a back that has muscles that like to spasm when being bent over i got it. As for testing it how far do you open the valve? Before I changed the OPS i opened the valve 3-4 turns and it stalled. That is how far I had to open it before any fuel came out. Is that to far of about right.
 

·
Registered
1995 GMC Suburban
Joined
·
17,730 Posts
Seriously, I have never paid attention to how far the valve have to be opened.
Till there is fuel come out. LOL!!!

Engine is engineering invention, it was made with tolerances not exact scientific measurement.
So, the valve is no different especially on a part that just have to be functional non mechanical to run the engine.
 

·
Registered
Joined
·
55 Posts
Discussion Starter #7
Seriously, I have never paid attention to how far the valve have to be opened.
Till there is fuel come out. LOL!!!

Engine is engineering invention, it was made with tolerances not exact scientific measurement.
So, the valve is no different especially on a part that just have to be functional non mechanical to run the engine.
Yeah i figured there wasn't a set number of turns. Drove it to work today and it seems to be better. Didn't have the misfire like problem that I have been having but it didn't always do it so time will tell.
 

·
Registered
1995 GMC Suburban
Joined
·
17,730 Posts
Yes, drive it for a few days.
 

·
Registered
Joined
·
2,483 Posts
I got up under the truck while it was running, used a metal rod and stuck it to the lp housing. Ear on the other end. It was running.

Cant hear it while the engine is on. No. Way.
 

·
Registered
Joined
·
357 Posts
I can hear mine run if i stand in just the right spot in relation to the truck and listen carefully. I have a delphi LP so it may be louder then the delco.
 

·
Registered
Joined
·
55 Posts
Discussion Starter #11
Well ive been driving it for a couple days. So far i haven't gotten the missfire feeling. Now just have to get the front end jacked up so i can find out what is making noise. Pretty sure its a wheel bearing.
 

·
Registered
1995 GMC Suburban
Joined
·
17,730 Posts
Sounds like you solve one of the problem.
 

·
Registered
Joined
·
55 Posts
Discussion Starter #13
Yeah solved one problem. Now on to others. Nothing like a low millage truck for its age needing a bunch on work.
 
1 - 13 of 13 Posts
Top