Hard start ... fuel issue repair

[bnlfan]

Okay, I have posted in the past about having an issue with the rv starting when it sits.  As it turns out, when you shut the motor down, fuel flows over the tank and onto the ground.


So apparently fuel drains back from the supply line and leaks out.  It only does it when you shut off the motor.


So, I will be pulling the tank and repairing the lines.  I will probably go ahead and change the pump.


Is this something I should photograph and post images of as I do the work?  It will be done in one day and likely one weekend over the next 30 days.

[M & J]

Pictures are always a plus. Plus, we love pictures. Right TJ?

[Oz]

Yes it definitely is.  You can continue posting it on this topic.  The 454 chevy fuel delivery system is always an issue of need for good pictures AND more important, detailed information of the process.

[bnlfan]

Planned to do the work this weekend.  But, I am in this cold front and live in the South.  I don't do cold.   Lol

[CapnDirk]

Define cold     It was 14 here this morning when I got up!  And this afternoon I'm working on the motorhome furnace that quit!  If that aint a visit from Murphy I don't know what is.   

[bnlfan]

Just a heads up.  The temp has finally climbed to a tolerable level so that I can start the work.
I won't bother with photo's of the first part of the fuel pump/tank repair. I simply will be spraying the nuts on the bolts that hold the fuel tank straps in place with nut buster lubricant.  I will be spraying them every day until the day I begin the repair.  Normally I would just heat the rusted nuts and bolts with a propane torch.  But, since this is at the gas tank, I think I will err on the side of caution. 

[circleD]

Smart thinking with the spray. Use a wire brush a day or two prior to get the rusty gunk off and it want get in the threads.  I did a post on here about my tank removal awhile back. Its hard for me to do links to show you. But here's some quick tips.
Get new bolts,washers, and nuts to replace the rusted ones.
FYI I had to make my own bolts with threaded rod and a welder.
Get a bunch of new fuel line. The supply and return are different sizes.
Check the wires on the sending unit and any wires on the frame while you can see them.
While the tank is down clean the tank and frame. Then paint it.
Measure the distance of tank so you know when it is all the way up when you reinstall it.
This is just my OCD two cents.

[CapnDirk]

BNLFAN:  You might look up a thread where Rick and I discussed lowering and raising the tank with threaded rods in all four corners.  From my experience having done mine a few months ago I would turn the straps loose on one side only and swing them 180 degrees,

[DRMousseau]

UGH! Always somewhat hated workin' with gasoline systems.

And I couldn't help but to recall those hard starting Chevy days! In between the assorted motorcycles and occasional European sports cars, there was always a Chevy (ok, so once there was a 69 Roadrunner in my life too). My first was 1935 Chevy 1 1/2 ton flatbed stake truck with a Stovebolt-6 much like the pic below. Cost me $35, a new battery and wiring harness to get on the road.

Seemed one thing in common with my Chevys, was the need to pump the daylights outa 'em BEFORE hittin' the ignition,... then keep pumpin' like mad till they came to life!!! Fords on the other hand, you only pumped ONCE!!! Anything more,... and it was flooded out!!!! Summer or winter, never mattered much. Hard to keep in mind with my current 460 powered apartment!!!

[bnlfan]

Well, it took some time but I finally got to get back to working on the rv.


Here is the actual source of the leak.  I had a friend turn it over while I checked it out and found that it is not coming from the fuel tank. It is coming from the item pictured here.  It is actually easy to access but I am not sure what it is exactly.  Unless one of you knowledgeable folks tell me, I will  be checking my manuals.


I will still post photo's as I do the repair.

The leak seems to be coming from the part with the four screws in it.  Like an o-ring is gone.

[stanDman111]

looks like a fuel regulator to me

[M & J]

Fuel pressure regulator. Search the forums for that. Theres one that has part numbers for a rebuild kit or a complete new unit.

[CapnDirk]

BNLFAN:


Fuel pressure regulator used from 1985 1/2 to 1989 maybe 90.  We are blessed with in tank electric fuel pumps and mechanical pump on the engine.  That regulator steps down the pressure to about 12-14 psi (working from memory).


Just did my whole fuel system a few months ago including that.  Rebuild kit (12-807) available on Ebay for less than 10 bucks and free shipping.  Can be done in chassis

[bluebird]

Be sure to use the correct color spring or the original if it is still good. Don't mess with the nut in the center of the plate, just remove the 4 screws and replace the diaphragm. You may still want to drop the tank to replace the fuel lines, as they will need it unless someone has already done it. If the rubber lines have not been replaced lately they will need to be replaced with lines that are compatible to fuel with ethanol. Ethanol will eat up the old rubber lines in no time and either leak or fall apart and plug up the carb ect.

[bnlfan]

Be sure to use the correct color spring or the original if it is still good. Don't mess with the nut in the center of the plate, just remove the 4 screws and replace the diaphragm. You may still want to drop the tank to replace the fuel lines, as they will need it unless someone has already done it. If the rubber lines have not been replaced lately they will need to be replaced with lines that are compatible to fuel with ethanol. Ethanol will eat up the old rubber lines in no time and either leak or fall apart and plug up the carb ect.

Good call on the lines.  I already ordered the rebuild kit and luckily it turns out the person selling them is in the next city over. So, I should have it in a short period of time.

[CapnDirk]

Something occurred to me.  If the regulator is messed up inside along with the leak problem, that would definitely contribute to a starting problem.


If you are going to do the hose from the tank to the regulator you will need to have it made at a hydraulic shop (be sure to ask them for fuel compatible hose)  that line is SAE on one end and Metric on the other.  You just about can't find it if at all.  The shop will use the one brass metric fitting.


Gotchas!  if you are going to drop the tank (see tread by Rick and I on suggesting using threaded rod to lower tank) it has to come down at an angle slopping to the other side of the fill hoses.  There is so little room that I could not get to the hose clamps INSIDE the frame rail next to the tank.  Next gotcha, put my tank in three times to have no fuel pressure.  Turned out that new hose on top was kinking due to the regulator being so close.  I had the shop that made the hose make it about ten inches longer so the next time the tank came out there would be enough to get the tank on the ground before having to turn it loose.  The solution wound up being a better idea than stock.  I moved the regulator about 8 inches outboard (out of the pocket).  This allows you to actually work with the hoses connected to it, and service it if needed.  It is almost impossible to work with it with the connections of the fuel lines hidden in the pocket between the tank and regulator.


Caution.  If you are going to move the regulator you will need to adjust the length of the hose the shop will make.  Don't have them duplicate what you have and then move the regulator.

[Mike_Rosoft]

watch out for the fuel pump start relay! it is no longer manufactured! basically its a 10 second priming circuit and low oil fuel pump safety cut off if the engine stops engine oil pressure monitor). Mine had gone because the low oil switch packs up... ( replaced mine and added a heavy duty relay to avoid switch burn out )  without this, my chieftain takes ages to start, always needing to start with MOM switch activated......