PDA

View Full Version : Lift Pump Replacement - Need New Fuel Lines?



trbankii
09-17-2010, 19:51
The '93 has been a bit hard to start lately. Takes a couple tries if it has sat for awhile. Once running, it is fine, and usually fine to start the rest of the day. Let it set for a day (or more) though and......

So leaned my head down with the door open and turned the key. No sound from the lift pump. Ok, easy enough to replace. Got a new ACDelco OPS while I was at it just to cover the bases.

Got the OPS changed easy enough. Used a 1-1/16 deep socket, although when I pulled it out I could see that wasn't quite the right size - perhaps metric?

Crawled under the truck to do the lift pump. Man! Do I hate the salted roads in winter... (see picture below)

The wetness on the lines is Kroil. They were dry before I sprayed them, so that isn't leaking diesel.

But I'm afraid that the fuel lines aren't going to hold up to disassembly. I looked on RockAuto and a GM Parts Direct and can get the supply and return lines from the tank to the pump (the return line also has a coupling right there). But I cannot find from the pump forward. Anyone have a source? Do I have to go to the dealer for those?

Or are the lines more robust than they look? Just soak them in penetrating fluid and hope for the best?

JTodd
09-18-2010, 18:44
Just soaking should do. If memory serves, both male and female ends of each connection is brass, so not as much internal corrosion as scale on the outside.

racer55
09-18-2010, 19:25
If you do need to replace the line I would expect that you can get a piece of 3/8 line with the nut and already flared properly for the nut and o-ring and a regular single flare on the other end from napa.Then just run neoprene the rest of the way to the filter housing.

I recently had the same problem on a 93 gasser when replacing the inline fuel filter,I expect they both take the same line.

trbankii
09-21-2010, 14:14
Ok, got everything replaced. The coupling at the front of the lift pump broke free without too much trouble. The rear coupling was a bit more problematic and at one point I was sure that I had twisted the fuel line. But all was well.

Now for a shower with Simple Green™ because, although I'm somewhat partial to the scent, not so many others are enamored of diesel fuel as a cologne... :p

racer55
09-21-2010, 14:19
Good work.

trbankii
09-22-2010, 18:58
So, how much difference in daily operation should this have made? I'm guessing that my lift pump has been underperforming for quite some time... Definitely a noticeable difference when you put your foot in it! :eek:

racer55
09-22-2010, 19:27
My lift pump failed while driving and the difference was noticable,big loss of power,I limped the truck home that way thinking the fuel filter got a rush of dirt and found out it was the lift pump when I tried to bleed the filter.
The new pump solved the problem but it was shortly thereafter that the pmd failed intermittantly from being in the stock location without enogh fuel to keep it cool.

Forums like this were the soloution to diagnose that problem and educated me on many other common problems we all face with these engines.

trbankii
09-22-2010, 21:14
Well, fortunately I don't have to worry about the PMD. I do plan to change the fuel filter. It has been awhile and I figure some debris may have been knocked loose in messing around with the pump.