New guy here. I recently picked up a decent '87 150 on a deal, knowing there was some kind of problem. I'm very mechanical but not familiar with this fuel system. It's a 302 with two fuel tanks. It was surging pretty bad when you tried to drive it. A friend who has a carb shop looked at it and said someone has taken the switch valve off the frame and disconnected the rear tank. He also said it has an outboard fuel pump that looks stock, and the missing switch valve has what looks like a fuel line replacement kit, because he says it fits perfectly where the switch should be, including the right Ford fuel line fittings.
I'd just as soon return it to stock so I can have both tanks.
Here's my questions:
1. Did some come with an outboard fuel pump?
2. Correct part number for switch valve.
3. There's got to be a number three......hmmmm. Well , something's bound to crop up.
To answer NO.1: The outboard fuel pump may be the high pressure fuel pump. The fuel injected F-150s up through the 1989 model year had a low pressure fuel pump in each tank and the high pressure external pump located in the driver side frame rail about right under where the driver sits. Starting with the 1990 model year, they put a high pressure pump in each tank and eliminated the external pump. I can't help you on NO.2.
The lines used to replace the switching valve have K&S Engineering on them.
Is this some kind of line kit to replace it?
Here's what's under my truck. My buddy did a pressure test and it showed it was down on pressure by 5 pounds. Enough to make a problem he said. I'm thinking the low pressure tank pump is not giving the HP pump enough to work with.
Need to test the tanks pump. Disconnect the line and run it into a bucket, turn the key on. Sound right?
Down down on pressure by 5 pounds from what?
How did he test it?
You should have 40-45 PSI at the fuel rail with pin #6 of the self-test plug grounded and the key on with the engine not running.
At idle you should have 30-34 PSI and then it should go to about 40 PSI @ WOT.
He said he used two test points where there's a schrader valve, somewhere up by the engine, where he screwed a pressure guage. Said there was 35 lbs where there should have been 40, and at another spot he said there was 30 when there should have been 35.
The truck runs fine a low low speed, say idle to about 25 mph. But if you try to go faster it will buck badly. It sure seems like low pressure.
There is only one point to take the reading. It does not sound like he grounded pin #6.
Sounds like he was just turning the key on and off.
Those reading would not mean much. Do it yourself or take it someplace where they know how to do it.
The $77 dollar price sounds reasonable. IS there another way to get to his site or another place to go?
And would you have the part number for the in-tank pump.
That link in Ford E is very old. It was for the part number and information on the valve only.
The only place I know you can get the selector valve is at a Ford dealership and they will have to order it.
The in-tank pump can be had at any Auto Parts store.
But I am not sure you have a fuel delivery problem and your pumps and valve may be OK.
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