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in-op fuel pump?

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Fellas: I recently acquired an '86 Commanche with a 4CYL motor

and 3-speed manual trans. It had been sitting and not run for about

five years. I changed oil, removed spark plugs and injected a bit of

oil into the cylinders. With plugs not tightened I turned the motor

over to lube up the dry walls. Turned easy without compression.

I buttoned up and cranked again. Motor would fire and run only with

eyther above the throttle body. No eyther, no run. I didn't continue

that process very long as I know it's not good for motor to run on eyther.

First suspect the fuel pump. Have 12 volts at tank going in.


Before I do the lengthy and difficult task of changing the fuel pump in

the tank, is there anything else I should check?


Should I expect any sound from an operable fuel pump. Past experience

on other vehicles lends to some others clicking and/or buzzing momentarily

when power applied.


I did see previous post here on ballast resistor on inner fender. Don't know

if it applies to this truck confirguration.


Anybody comment on the task of changing the existing fuel pump?

Anybody know the fuel pressure required? I thought of buying an aux

pump and installing in-line but those are only 4-6 PSI. I doubt that is

enough for a throttle body.


Any advice / suggestions appreciated.

Windancer in Michigan Aug 7th 09

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I don't know about the '86, but changing the pump on my 87 only took about an hour with an aftermarket pump. It did not require any modification other than a large hose clamp to keep it in place and puts out about 35psi at the injector rail. Also a good idea to buy a new filter screen for the pump inlet after sitting that long. If it still had gas in it after sitting that long there is probably some sludge in the bottom of the tank also.

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