I think it's a fuel pump issue?

I've been working on my H1 for a few months now getting it back to its fighting weight. I've been noticing that the purring that comes from the fuel pump/lift pump(not sure which one purrs) has been getting louder when I'm starting up. It's noticeable while driving too. If I cold start it and turn it off before it warms up the pump makes noise for about 3 secs after the key is off too. If the truck is warmed up it won't make the noise when I shut it off, but is still loud when running.


Yesterday I half turned to the key to warm up the glow plugs like normal and I got no purring at all.... It still turned over after the wait light shut off and ran till I shut if off. I thought my neutral safety switch went out again, but that's not the case. Do I need to pick up a new fuel pump? How is it still pumping diesel into the engine if it is out? Looking for some light on this potential issue... Thanks in advance!

Could be. What year is the truck? My 92 and 94 fuel pumps run after I turn the truck off, not before. My 98 runs before the wait light goes off. I have had pumps fail after getting much louder but usually the clicking gets erratic for awhile before they have failed. Not a hard replacement usually. I had one I had to remove the doghouse on because of how the clamp was installed. Make sure they are easy to get to from the engine compartment for an easy install next time. There are numerous pumps that will fit but make sure you get the high volume pump.

3Hummers said:

Could be. What year is the truck? My 92 and 94 fuel pumps run after I turn the truck off, not before. My 98 runs before the wait light goes off. I have had pumps fail after getting much louder but usually the clicking gets erratic for awhile before they have failed. Not a hard replacement usually. I had one I had to remove the doghouse on because of how the clamp was installed. Make sure they are easy to get to from the engine compartment for an easy install next time. There are numerous pumps that will fit but make sure you get the high volume pump.

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It's a 1997 1/2 H1 wagon. Do you have any certain pumps you would recommend for this replacement?

When I get home this weekend I can get you a part number.

3Hummers said:

When I get home this weekend I can get you a part number.

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Thank you!

[h=1]6010682[/h]

GM part number is 15754298. $79.66 on GM Parts Direct according to Mike.

Glad I came across this post as i was wondering on what fuel pump to install. I have already done a lot of job and even replaced some fuel hoses that looked weak to me (here is what I bought https://www.carid.com/fuel-hoses/). Though the sound and bad starting was not fixed. So now I feel that the pump has to be replaced, as there are exactly the same symptoms as described here. I will do the last attempt (will take my H1 to the diagnostics) and then most probably will shop for a new pump. Luckily now I know what I need