ofcmarc

Got off Work last night and my '92 quit on me.

Started it up and it ran ruogh fo a minute, wouldn't pull ant RPMs, then died.

I cracked a couple of fuel lines and got nothing. No fuel on either the low side or the high side.

Lift pump lever hasn't worked well in over a year but I just figured that it was my bad luck to ALWAYS land on the wrong spot on the cam lobe.

The worst part is that I don't have all the parts to do a 2nd gen piston pump mod yet. I need the truck so I'll have to find a diaphram pump today and go with that for a while.

Guess I should use that FP gauge that's been sitting on my tool box for a while now.

BearKiller

My guess is that your lift-pump has probably been dead for quite some time.

Stick an el-cheapo electric on there, while you are gathering the stuff for the piston-pump swap-over.

ofcmarc

I would but I think it will be easier to just put a stock diaphram on there laying in the snow than to splice into a line with an electric.

The local NAPA has one on the shelf I'll put in after work.

BearKiller

Laying in the snow ???

What have you been smoking ???

I just looked and it is 92* outside and the sun would burn a blister.

ofcmarc

Started snowing 2 days ago. Hasn't stopped yet. Real light snow but the first layer turned to ice right away.

ofcmarc

Got the new lift pump in last night after work. Only took an hour to do. It had warmed uo to 30* so it wasn't hardly uncomfortalble working.

The pump must have been dead (or dying) for a while cause she really rolls some coal now when I stand on it. Lot's more that it did with the old one in. Guess I'll have to tweak the IP more now. Dang.

ofcmarc

Anyone Know what the fitting size is for the diaphram LP outlet. I need to fic a samll leak after the parking lot repair and I'd like to put on flex lines instead of the hard lines from the pump to filter head.

Thanks

BearKiller

I have succeeded in using 1/4 NPT fittings on several of them.

It is not actually pipe thread, though; the pitch is correct, but the threads are straight, instead of tapered.

BUT, I have gotten around that by using Permatex thread sealant and giving that little extra half-turn, when tightening; if it drips, then I give it a little more.

The fitting at the filter is 12mm-1.5 metric, or somesuch.

Glacier Diesel has adapters for those; but, interestingly enough, they don't have them to fit the lift-pump.

ofcmarc

Thank you sir.

BearKiller

At the filter end of things, one might get away with cutting the metal tube a couple inches long, and forming a raised lip around the perimeter of the tube, such that a hose could be slipped over the tube, and the lip retain the clamp.

I have had some success by laying a tube on a block of soft wood and using a specially ground punch/chisel to form the ridge by striking from the inside out.

You might get along better by first raising the perimeter with a pipe flaring tool.

I hope some of this makes sense.

ofcmarc

I have a GDP Big line kit That I figure on installing soon (FP gauge too). It came with an extra 12mm fitting that I plan on using at the filter head (fuel heater?). I almost ordered the "maximizer" kit that came with more push lock hose and a few more fittings and and seals. I was strapped for $$ when I ordered it and figured I didn't really need it. Too late now.

If I can get a 1/4" pipe thread fitting (or the stock line)to seal I 'll make out OK until I get my 2nd gen LP. The pressure regulator from Vulcan Performance showed up the day I changed the pump of course. I may just plumb it in with the big line when I do it. It should'nt hurt anything. I dont figure the diaphram pump makes enough pressure to open it anyway.

BearKiller

The inlet and outlet of the piston-pump have the same threads as the diaphragm pump.

In your situation, and what I do, I would get enough 1/4NPT fuel-hose fittings, or hose-barbs, to do both pumps.

A 90* 1/4NPT works best at the outlet end, although a straight can be used.

This way, when you do install the piston-pump, you can leave the NPT fittings, on the diaphragm-pump, un-molested, since you have them already installed leak-free, and should you ever need to re-install the diaphragm-pump, you won't have to mess with the fittings.


Also, and I figure you already know this, although either will work with fuel-hose, there is a difference in hose-barbs and fuel-line-fittings.

The hose-barbs are "barbed", making future hose removal, without damaging a hose, almost impossible; whereas, fuel-line-fittings are, for the most part, smooth-shanked, with a smooth rolled lip at the end.

A hose can be easily pulled off of a fuel-line-fitting and re-installed, several times, without harming the hose.

When I can't get the good ones, I use barbs; they are just harder to remove the hose from, if needed.

ofcmarc

^^^

A fountian of knowledge a good advice you are sir. Thank you.

ofcmarc

I got the fuel leak fixed last night. At $3.00/gal even a little drip is expensive. The leak was from the banjo washers at the filter inlet. Near as I could tell they were original (made of fiber or some such). It feels like the truck runs better with a new LP and no leaks but the SOTP dyno is closed for the season.



I'll get to the bigline and bypass when I get a chance to get into a garage.