Just got my truck running after installing a new fuel pump. I have a fluid filled 100 # gauge installed where the schrader valve was.

Started the engine and after a short time I went around to look at the pressure and it was ZERO. Crap.

Turned off the engine, went back to the gauge and tapped on it w/no response. Closer inspection the pointer was resting on the back side of the pin. Oh Crap.

Started to remove the gauge and as diesel started seeping out the needle started to move counter clock wise.

Zero starts at approx, 8 o'clock and 100 is at the 4 o'clock position. Which means that I have about 120-140 # pressure. Oh Crap

Now what do I do? I have codes of 03-P1000, 02-1395, 01-P0475
none of which are on my code sheet.

Rog

 

You need to get it back down into the 70-80psi range

Did you shim the fuel pressure regulator?

 

I removed the BB shim befor I started to replace the pump. Possibly tomorrow I put that buffer in to see what kind of reading I get then

 

Holy crap, I think I really have a problem. The mechanical gauge did a complete 360* when I started the engine and indicated 100+ maybe another 20-30 # of fuel pressure, I don't know much actually becuz it was off the scale.

That is pretty high fuel pressure. I have no mods connected to this truck that has anything to do with fuel.

I removed the mechanical gauge and installed an electric gauge with a spike buffer between it and the schroader valve location. Started the engine and immediatly pegged the elect. gauge at 103#. (Couldn't go any further.)

I know I have to get it down but HOW???

Gads, everybody is trying to increase their pressure and her3 I sit with pressure to spare.

There just has to be a way.

Rog

 

did you make sure the regulator isnt stuck or the spring in crooked?

 

Joe:
No I haven't but I have not taken that apart since I started working on replacing the pump. I have thought of that though and it's on my list of things to do tomorrow.

I just came back from a local diesel garage and they are familar with the 7.3 PSD. One thought they had was a possible blockage in the return to tank line. I don't think that has happened but????.

The two (2) threaded lines that are on the front (Between filter and HPOP if buy chance they got crossed could that cause high pressure? I don't even know what they are, where they come from or go too.

While at their shop I looked at their manuel and it said that the factory setting is 40psi, well I've got all of that. I will check for blockage but I was thinking what if this new pump Just happens to put out 100#.

We have used the BB to increase the pressure... could shortning the spring bring the pressure down?

The only good think is that the old pump was putting out 10-20# and I would have become stranded some day.

Rog

 

roger,its the gm h2o. kurt

 

Kurt, ya can't blame this on my Cadillac Battery Water, were talkin' Diesel here!!

Rog

 

i don't get it what is cadillac battery water???

 

PSD:
It's an old joke like...Peterbilt air in your tires or Mercedes washer fluid,, etc,etc.

What the hell, Kurt got it.

Rog

 

kawa, pull your FPR and take it apart and check everything. It sounds like the relief valve on the FPR is stuck. The way the system works is: the fuel pump draws fuel from the tank and pumps it through the filter assembly at low pressure. The fuel then returns to the high side of the pump and is pumped out under high pressure (over 100 psi) through the banjo fitting, through the heads, and then to the FPR, where a relief valve bleeds off pressure to get the desired pressure and the excess is sent back to the tank. Just my $.02

 

Some Chromed Muffler Bearings are just the trick to fix this.
I have a set right here for ya.
Hell I'll give em to ya for a qt of elbow Grease

GJ plowhand.
I would think he has regulator problems also.

 

Talyn there is a muffler bearing. On the old pete's rubber groment that held the muffler to the cab was called a muffler bearing.

 

Remember also that your truck is a Cali truck.
It will have around 75psi at idle not the 40psi that the 49 state has.
Spool valve between the 2 are not setup the same.
The BB mod is for 49 state not Cali.
The 2 lines from the front of the heads are return lines. Crossing them will do nothing. They dump into the regulator.

As stated above sounds like defective regulator. But while you are in there blow some air down the return line to see if clear.

BTW---2 different part#'s for regulators. Cali and 49 state.

Bill

 

Thanks Bill,
Pulling the FPR is the first task of the AM
Rog

OH, and about the chrome muffler bearing, the reason they are so chear is because they have been replaced with "Carbon Fiber" plus my arm hurts so dang bad I have a large supply of elbow grease. What I really need is turn signal fluid.