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markrinker
07-30-2004, 05:59
Quick reminder, please - what is the trick for engaging the lift pump with the engine shut off?

Neutral with key in 'on' position?
JohnC
07-30-2004, 06:36
Any gear EXCEPT park or neutral, key to start.
whatnot
07-30-2004, 15:16
Originally posted by JohnC:
Any gear EXCEPT park or neutral, key to start. That won't work on a '94
tom.mcinerney
07-30-2004, 17:43
On '94 can't he use the fuel/LP relay?? I recall posts to that effect...
markrinker
07-31-2004, 07:38
Talk to me, Tom. What is the fuel/LP relay and where is it located? Could this be related to my other thread re: Stalling and hard restart after re-fueling?

Truck #1 has a rather noisy LP when using the 'test' above - in gear.

Truck #2 makes no noise with same test. Will use voltmeter today to see if its not getting power, or burned out again. (It was just replaced last fall.)
whatnot
07-31-2004, 17:03
Originally posted by Mark Rinker:
Talk to me, Tom. What is the fuel/LP relay and where is it located? Could this be related to my other thread re: Stalling and hard restart after re-fueling?

Truck #1 has a rather noisy LP when using the 'test' above - in gear.

Truck #2 makes no noise with same test. Will use voltmeter today to see if its not getting power, or burned out again. (It was just replaced last fall.) Doesn't it lock the key so you can't turn it all the way unless you are in neutral or park? My '93 does and I was positive that my brother's 94 did too.
My '95 (new style interior) can turn the key all the way in any gear selection.
tom.mcinerney
07-31-2004, 20:10
Mark--not sure about '94--But i think that on pre-'96 the LP is energized by OPS when key in RUN; and LP is energized by fuel pump relay when key in START(crank). On mine the relay is in underhood fuse/relay box; yours probably along firewall...can check other truck for locus??
moondoggie
08-02-2004, 07:40
Good Day!

To check your lift pump, you might want to see my 3 June 04 post. (http://forum.thedieselpage.com/cgi-bin/ultimatebb.cgi?ubb=get_topic&f=1&t=006553#000014) (Click in colored text.) This might not apply to your year of truck, but if it does