Bruski Posted August 7, 2009 Share Posted August 7, 2009 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 Link to comment Share on other sites More sharing options...
Geonovast Posted August 7, 2009 Share Posted August 7, 2009 5 year old gas. 3 speed? :hmm: AFAIK there were 4 and 5 speeds available, the automatic was a 3 speed. Link to comment Share on other sites More sharing options...
Mongo Posted August 8, 2009 Share Posted August 8, 2009 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. Link to comment Share on other sites More sharing options...
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now