92 RR not getting fuel to rail

My 92 Classic sputtered to a halt today. I figured I ran out of fuel, so I put about a 1/2 gallan in. I haven't been able to start it since. I pulled the fuel line at the rail and it is not getting any fuel up there. I concluded that it was fuel relay, fuel inertia, or fuel pump. I checked the pump w/12volt lamp and ignition on and I am getting no light, so it appears that the pump is not getting power. I checked the inertia switch and even jumped it there, no fuel to rail. i tried the 12v lamp at the inertia wires /doesn't light up? I also swapped the identical relays (fuel pump relay and ecu relay) under the right seat. No cahnge. I don't notice any clicking from under there with ignition on. What are the odds that both those relay are done. How do I test those relay? Any ideas about any of this would be greatly appreciated.

joe myers

Reply to
doobashoe
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Joe

I haven't got time at the moment to check whether your system is the same as a 1988 model but the following or something similar may apply. There were changes for the 1991 model year but I don't yet know what was involved.

There is no electrical supply to the pump unless either the engine is cranking or the engine is running (determined by air flow through the flapper valve - assuming that this is the version that you have). A static test as you seem to describe won't run the pump unless you inject volts at an appropriate point. There is also the over-run shutoff relay near the left hand suspension tower.

Assuming that this is not just an empty tank problem (which half a gallon probably won't cure) poor/broken connections at the last connection before the pump and at the over-run shutoff relay are not unknown.

Do you have a copy of the circuit diagram? I knocked something up for the earlier model which I'll happily send you if you can confirm a good e-mail address. I might also be able to find the same for your model given more time.

David

Reply to
Dougal
92 3.9 has the hotwire airflow and I see no over run shut off. fuse is good. I have run out of gas before and even less than 1/2 gal. worked. I haven't pulled he fuel filter to see if it clogged, but it rarely get that blocked. anyway, I'm not getting power to the pump, so it's ahead of that somewhere. batterys gone now so I'll have to get that charge and continue the search. The 12v lamp lights and the coil pos when ignition on, where would the next lamp test be?

joe m.

Reply to
doobashoe

On or around 12 Mar 2005 08:42:11 -0800, snipped-for-privacy@yahoo.com enlightened us thusly:

it's got a pump relay somewhere though, which only energizes when the engine's turning. You should get power to the pump for the first few seconds after turning on the ignition, mind.

have an assistant crank the engine, test for power at the pump while it's cranking.

I can look it up, but I suspect that it gets a signal from the ECU on the hotwire, which in turn knows whether the engine's turning either from ignition impulses or from the fuel side.

improvise with a suitable length of wire from a 12V supply direct to the pump, see if the pump runs. If so, see if the engine runs. This will eliminate the pump.

Reply to
Austin Shackles

In message , snipped-for-privacy@yahoo.com writes

Hi

under the carpet behind the front passenger seat (RHD) You will find the wiring for the inertia switch. There is a join here that can corrode / burn out. Have a look and see if that is the problem.

Good luck

Reply to
Marc Draper

worked.

Prior to taking in the battery I disconnected the fuel filter under the right wheel. I then set the battery on the tail gate and jumped it directly to the fuel pump. Now, the battery isn't charged enough to crank the engine, but certainly it would have enough to power the pump. When I do this, I hear the pump running but it is not pumping out fuel at the line under the right wheel, which I believe it should. Perhaps the pump is sounding but not pumping? Could there be an obstruction in the tank (pump) that would completely block ALL the fuel? I am trying to avoid removing the pump.

joe m.

Reply to
doobashoe

On or around 12 Mar 2005 09:44:05 -0800, snipped-for-privacy@yahoo.com enlightened us thusly:

you have put some more petrol in the tank, I assume...:-)

Reply to
Austin Shackles

Well, when I ran out I put in a 1/2 gallon. Now, I have run out before and put in less and had no trouble. when the battery is done being charged I will drop in another gallon? and see. I just know from before it has taken less to get it going again. I shall see. But it should be putting out fuel at the filter line under the wheel, shouldn't it?

joe m.

Reply to
doobashoe

On or around 12 Mar 2005 10:06:42 -0800, snipped-for-privacy@yahoo.com enlightened us thusly:

yes.

try it with a full 12V though.

Reply to
Austin Shackles

Put a full 12v to pump. No fuel out of line. Sounds to me as if the pump is running but not pumping. Diaphram? Clog I do not see that it could be anything else. ???? I'll put a gallon in when I get the battery back from recharge. It it doesn't work then, it has to be the pump.

joe m.

Reply to
doobashoe

In news: snipped-for-privacy@o13g2000cwo.googlegroups.com, snipped-for-privacy@yahoo.com blithered:

What side of the underwing fuel filter are you looking @? If you've sucked all the sludge out of the tank its probably mostly in that filter and making an effective lump out of it.

Reply to
GbH

I took the filter completely off, so I'm getting no fuel prior to the filter.

jm

Reply to
doobashoe

On or around 12 Mar 2005 11:56:15 -0800, snipped-for-privacy@yahoo.com enlightened us thusly:

I reckon the pump may be your culprit, then.

Reply to
Austin Shackles

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