It most certainly WAS

 

I see two #18 fuse links looks like I will have to cut them some way to test themBut like I posted there was no movement on the fuel gauge even before the pump stopped do you think that mabey the tank pumps are still good? (opinon)?

 

That tank pump was making a lot of noise so it could have been what opened the fuse link.
Are you sure you did not get the hot wire at the frame pump shorted to ground when you changed it?

To test a fuse link just try to pull it apart, if it stretches it is bad.

 

OK! but bye this being sat nite I am going to try what you suggested sun but mabey not post, is there enything else you can think of to try ? no way to short out the chassis pump the electrical snaps together, we tested all the fuses (glass) that we saw you Know come to think of it I cannot Pull allose the fuel pump relay sh&*&t I just thought of that!I tried to pull it apart and even with a screwdriver I could,t pry it apart do You think .......mabey?

 

I do not understand what you are saying about the fuel pump relay.

 

In message #15 ypu posted a picture of what the fuel pump relay should look like, Well I cannot pull a-loose the relay from the socket seems like it,s welded or something at first I dismissed it because I was looking for the reason to be somewhere else But well I dunno,....

 

The relays and their sockets should come apart.

The sockets (note the FP relay is missing one wire):


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while sitting here thinking about this motorhome, I am trying to figure out what happened in the first place!I arrived at my destination every thing in working order, after being parked for a year,only started ,and the next day I was going to get some propane for the fridge, and No start!when I did get it started engine was running rough ..sputtering and then dieing. I thought since it had been sitting, mabey the Plugs and wires need to be replaced did all that and still no go .since it was safely parked I let it sit looking for info (did not try the internet) and could fine no one to advise me I just let it sit over the winter..then this july I decided i wanted to try to get it running in order to Use It,and while it mostley is acting the same after replacing these items

cap rotor
wires
fuelpressure reg
chassis fuel pump
I am wondering if I have lost a signal or some voltage supply
what accuates the chassis fuel pump(boost)
since there is NO pressure to the fuel rail
and since the pump in the tank WAS working it goes to the chassis pump (which was replaced)and the chassis pump is suppose to (act like a step up transformer)
increase the pressure to the specific amount as to properley fire the injectors.AS i looked at the diagram I was sent, there is nothing in between the fuel tank and the fuel rail BUT the boost Pump so What turns that on?
is it the 7psi from the fuel tank pump?and incidently the chassis fuel pump I replaced is running strong(when 12v is applied)
and that is where I am at now......

 

Sorry Bill I didn,t know you were up this early good morn! the relay socket does not come apart !(pull, tug ..pry)

 

The high pressure fuel pump on the frame is turned on by the fuel pump relay by way of the Inertia Fuel Shut-Off switch.
See text below.

The Power from the Starter solenoid battery side goes through a fuse link and then over a Yellow wire to the Fuel pump relays common contact. The Fuel pump relays NO contact is connected to a wire that goes to the Inertia Fuel Shut-Off switch common contact. When the fuel pumps relay coil is grounded by the EEC Computer pin #22 the relay closes and power goes from the NO contact to send this power to the Inertia Fuel Shut-Off switch. The Fuel pump relays other coil wire is powered by the EEC Power Relays NO contact and it closes when the key is turned on. The NO contact also power the computer to run and the computer then grounds the fuel pump coil for one second and will not do it again until it sees a PIP pulse from the Distributor.

The Inertia Switch contacts are NC unless tripped so the Inertia Switch contacts sends power to the High Pressure fuel pump on the frame and to the Fuel Tank selector switch at the dash. The selector switch sends power to the selected in tank pump and gauge sender (the power for the gauge sender comes from the gauge cluster and not the Inertia Switch).

The fuel leaving the in-tank pump goes to the fuel tank selector valve on the frame and the 7-10 PSI fuel pressure is applied to the diaphragm inside the selector valve switching it to the selected tank for the supply and return fuel lines. The 7-10 PSI fuel then leaves the fuel tank selector valve and goes to the high pressure fuel pump where it is boosted to a higher pressure (about 100 PSI to a blocked head). The high pressure fuel then goes through a fuel injector filter and then on to the fuel rail on the engine.

There is a vacuum fuel pressure regulator also on the fuel rail that relives the fuel pressure on the fuel rail to 32-45 PSI depending on the vacuum it gets from the intake manifold. The extra fuel to relieve the pressure is sent back to the fuel selector valve where it is routed back to the selected fuel tank.

The Fuel injectors are also attached to the fuel rail and are grounded by the computer in groups (banks) of four when the computer sees PIP pulses from the distributor. They are grounded for a time period depending on the position of the TPS attached to the throttle & the MAP sensor.

 

Good morning Bill, thank you for this lesson on fuel injection! I can see in my mind how ithe fuel travels.and it all starts at Key on I may have to replace the fuel pump relay ..is there a part number? ..I cannot get it a-loose somehow it has welded it,s self together I can,t even PRY it apart.I located the inertia switch I know where the Tank Switch is And also the tank switching apperatus.I should be home Free,when replacement of the FPRelay happens, the tank pump should become operational(I Hope)and mabey I can find out why the Chassis Pump will not engauge.I looked at the inertia switch and I see no button to try to reset it.(nothing to push)

 

There should be a red button on top of the Inertia switch to reset it.



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my red button up there will not push.no matter how hard I push...does it only push if it has tripped out?

 

Yes I think so.
Just take a test light and check the wires going into it and out of it. If you have power there with pin #6 grounded of the EEC self-test plug and the key on then the switch and the fuel pump relay are OK.

 

OK! now that I have taken the test light and confirmed that the FP relay is working,( if I take out the relay and insert the light it will glow DIM)I get no noise from the tank pump( remember you said it didnt sound so good) I guessing that now it has possibley failed. but if I switch tanks(on selector) no pump action either way..... I know/guessing that I have not lost a groung because the fuel gauge sender works..(on both)other than droping the tanks, is there eny other way to assure the tank pumps are short?/or have quit.... eny kind of guess is acceptable mabey an old mechanic trick or something. I,ll try enything before I have to tackle the tanks........