Fuel leak behind rear wheels

[piorun]

I have a fuel leak on passenger side behind rear wheels. Anyone knows what it is.  Looks like some kind of valve or something.

[DaveVA78Chieftain]

88 P30 would have a in-tank electric fuel pump.  That is the external fuel pressure regulator GM P/N 15598336.
There is also a fuel filter halfway between front and back wheels.

[piorun]

Do I have to drop fuel tank to change it?

[DaveVA78Chieftain]

I would not think you would have to drop the tank to change the regulator however,
the typical problem is that the old rubber hoses that are used all along the fuel line (tank to carb) rot out with time.  Having a pressurized system you will find failure with those easily.

Dave

[piorun]

Anybody sells that part? I am having tough time finding it on-line.

[DaveVA78Chieftain]

I think it is no longer available.  You will have to replace it with a Holley 12-803 as described here: http://barthmobile.com/eve/forums/a/tpc/f/3631087061/m/8671029061

Dave

[piorun]

Thanks for the info. I am going to look into it. Hopefully I don't have to drop my tank because it is full.

[LRAYVICK]

I have an 86 Chieftain 27RT.  I have a similar weep/leak and have concluded I have to drop the tank to get to the hoses.   It doesn't seem to leak when running only somewhat after I shut the motor off.  Then it just barely leaks.  The gas tank hides the connections to the regulator which are inside the frame.   

[GONMAD]

That regulator is nothing more tha a holley pressure regulator available at any advance parts store or summit racing. They're about $45 or $50. The tank must be dropped slightly & use heavy duty fuel line dose & double the hose clamps. It's best if you REMOVE it from there I put it up front as the low pressure has a hard time going through the line for that distance THIS new way supplies FULL PUMP pressure to the reg a7 then lowers it to the 4-7 lbs. I set them at 5 lbs & it always helps to run NEW steel lines. I have had the original lines get porous when they LOOK fine. DO NOT take the chance.  That should solve any problems from that area for a while
  C YA! GONMAD

[piorun]

Thanks a lot. I guess I will take short trip before I drop the tank.

[piorun]

I got it changed. I used Holley part 12-803. I had to buy a plug to block one outlet on new pressure regulator. I was able to do it without droping the tank. It took about 2 hours to complete.

[ClydesdaleKevin]

Great info to know, Piorun!  Glad you got it all fixed and back together without having to drop the fuel tank.  Good job!

Kev

[rnrphoto98]

MY 88 Elandan seems to be having the same problem.  I have not been able to get under it very well to get a good look at the regulator.  How do the fuel lines attach to the regulator, is it just with clamps or are there special fittings.  I am really gratefull for all the great info on this forum.
Thanks

Rob

[piorun]

Inlet side srews in, outlet has a rubber hose with clamps. All fittings can be moved over from old regulator to new one.

[summerlin51]

I just repaired mine using the repair kit, Holly 12-807, you can do it where it sits if it is leaking without removing it.  A diaphram and two springs is all it is, as the above photo shows 4 screws, remove them and replace the spring and diaphram, shouldn't have to check your fuel pressure as long as you don't miscount or adjust the turns on the regulator.  FWIW, after i changed mine my rig ran just fine for about 10 minutes then died lack of fuel, being I had just replaced my fuel pump and repair the bad diaphram in the regulator I was stumped.  The fuel pump working no fuel at carb, aha, not enough gas (only 3 gallons and I cleaned the entire line all the way to carb using new gas etc.  Got 5 gallons more didn't help.  Removed inlet to regulator turned on key, LOTS of gas. Took reg apart again, aha, the check valve was stuck, cleaned with penetrating oil and lots of exercise on the set screw.   Now works like a charm.