1987 Itasca Starts then died, now won't start at all

[jleo313]

Got in the motorhome yesterday and turned the key.  It fired, but then died.  I turned the key more and it wouldnt turn over.  I sprayed carb cleaner in the carb and it starts, but when the cleaner burns off it dies (a few seconds). I poured gas in carb and does the same thing as the carb cleaner.  It is like the fuel is not getting to the carb.  I replaced the fuel filter half way between engine and back of RV.  Still the same.  Where is the other fuel filter at?  What else should I do to trouble shoot.  I am far from a mechanic, so please use layman terms. 

Any help is appreciated! 

[brians1969]

My first thought would be the fuel pump. If it is in the tank, you should hear it when the ignition switch is turned to the on position. Take the gas cap off and listen while someone turns the ignition on. (Assuming the pump is in the tank) Check the fuse for it also....maybe fuel pump relay.

brian

[DonD]

Most need oil pressure to power up the in tank pump.

There's another filter in the carb inlet, assuming you have a carb.
Is the new filter arrow pointing the right direction?

[jleo313]

I went to autozone and bought the inline fuel filter that apparently is at the base of the carb.  An individual at Autozone believed it was a fuel pump from what I described.  It is the P30 chasis and I think I saw the fuel pump near the block.  I had followed the fuel lines back to this, so I am assuming it is the fuel pump??  There is a mobile mechanic here that I am thinking of calling, but I would much rather save the money and do it myself if I can.

Good news is the fuel pump is only 35 ish dollars...

[ClydesdaleKevin]

Take a deep breath and proceed from there...no need to panic.  We have the same setup as yours and its easy to troubleshoot.

The carburetor fuel filter housing is actually threaded into the body of the carb near the front...farthest from you when you open your doghouse and look at your engine.

Turn your ignition key to "On", then crawl under the RV and listen at your fuel tank...you should hear a hum from the in-the-tank electric fuel pump.  Chevy added an additional fuel pump to stop vapor lock, so your RV actually has 2...one in the tank, and a mechanical one on the engine block. 

If you aren't hearing a hum, then either the pump is bad, or the wiring to the pump is bad.

If its humming, chances are its still good, so its probably the mechanical pump.

There is also a fuel pressure regulator near the gas tank, but I'm not sure if they can go bad to the point they stop fuel flow.

And don't overlook the obvious...your fuel gauge could be bad and you might be out of gas.  Are you sure there is gas in the tank?

Kev

[DonD]

Look at #3 in the dwg and see post 2.

[jleo313]

Thank you guys for the answers and support.  So last night I changed the filter at the carb, although it looked ok to me.  I did not know that there was two fuel pumps...now that I do I am hoping and praying it is not in the tank.

The mechanical one at the block was replaced in 07, but it sat for a while.

I put a hose on end of fuel line near carb and cranked engine.  Gas did come out, but it did not have much pressure at all...my finger could easily resist what was coming out. 

I bought the new mechanical pump at the block and am having a guy install it today while I am at work.  Yet, after reading this I am fearful that it is the one in the tank.

How hard is it to replace the one in the tank?  Hm?

[jleo313]

Kevin,

I did check the fuel, and added some to ensure that it wasnt that at the onset.  I was really hoping that was the issue...but I am not that lucky.

[DonD]

Most need oil pressure to power up the in tank pump.

There's another filter in the carb inlet, assuming you have a carb.
Is the new filter arrow pointing the right direction?

I must correct my post, the oil pressure controlled FP switch is there to STOP the electric fuel pump in case of no oil pressure, as in when the engine stalls etc. There's a relay on the firewall that starts the pump. I'm still learning here too!

http://www.irv2.com/forums/f65/1985-p30-chassis-where-is-the-fuel-pump-relay-61112-2.html

[jleo313]

Thanks Don!  So per your link, there could possibly be a fuel pump on the rail outside of the tank?  Am I correct in saying this?  I am sure it is either or, in regards to in the tank or on outside rail....

[DonD]

As the extra fuel pump is a MH manufacturer installed item I suppose it could be anywhere but...It is most likely in the tank, mine is but there's a regulator in the frame rail near the tank.

[ClydesdaleKevin]

You can rule out the pump in the tank by turning the key to on and listening at the tank.  Usually, if its humming its working...not always, but usually.

Kev

[jleo313]

Little update...Took yall advice and listened for the humming sound....there was none.  I decided it was the in tank fuel pump.  After dropping the tank (not fun), took the old one out, placed the new one in and tested.   Hm?    Engine turned over and everything is working as it should.

Thank you guys for the information.  I could NEVER have done this without yall's advice!!

Jarrod

[Oz]

Wow, that was some fast and furious work there!  Glad you got it running 

[DonD]

EXCELLENT!!

What kind/brand of pump is it Jarrod?

[ClydesdaleKevin]

Outstanding!  Glad you got it all worked out!   

Kev

[DonD]

Found a note from Fleetwood that may help in the future:

Fuel pumpsâ€"P-30 Chevrolet 1980’s Electric booster gas fuel pump, (Fleetwood installed) 1980’s P-30 Chevrolet Class A Chassis.

This fuel pump was normally located on the outer passenger side rear rail, right in alignment with the fuel tank. The fuel pump may be a Holly Model ST802 or a Carter or a Walbro. The engine oil pressure switch normally controlled this electric fuel pump. After the engine is started, the oil pressure switch sends power to a bulkhead Bosch relay
that then sends power to the electric booster fuel pump. There are two fuses in the circuit. One for the oil pressure switch, and one for the bulkhead relay.

The Chevrolet OEM vacuum fuel pump was still used and located at the engine front, passenger side lower area. The additional electric fuel pump was added for vapor lock conditions and lack of fuel in certain situations.

When the Fleetwood installed electric fuel pump fails, the engine has a hard time running as the engine is starving for fuel. By-passing the fuel line around the electric fuel pump is ok for an emergency repair situation as long as a Dealer/mechanic does this as a temporary repair.

(Note) We have found some Chevrolet chassis that have an OEM electric fuel pump in the gas tank along with the side mounted electric fuel pump installed by Fleetwood.

[DaveVA78Chieftain]

For future reference:
At the top of the first page of the Manuals, Diagrams, & Tech Info section in the Member area is a link to the free book Chevy/GM P-30 Chassis Service and Maintenance.  Starting on pdf page 135 is an in-depth discussion about Vapor Lock and the different P32 fuel system designs used in the 80's.  Describes adding a electric fuel pump, which ones used an external electric fuel pump and which ones used an in-tank electric fuel pump.
The remainder of that book contains a lot of useful GM P32 information.

Dave
 

[gadgetman]

I must correct my post, the oil pressure controlled FP switch is there to STOP the electric fuel pump in case of no oil pressure, as in when the engine stalls etc. There's a relay on the firewall that starts the pump. I'm still learning here too!

http://www.irv2.com/forums/f65/1985-p30-chassis-where-is-the-fuel-pump-relay-61112-2.html

Actually its there so if you crash and the key is still on the electric pump wont continue to run with the engine off. Granted no oil pressure will also shut it down but its not the main reason they use it. its a fire prevention switch.