94 won't start - Diesel Forum

ddwwmm · 06-24-2007, 11:18 AM

help, i have a 94 7.3 not a powerstroke but with the Ford turbo, 175,000 miles and well maintained. i have a couple of problems, when the truck is cold, it takes about a minute -sometimes longer- to start, but once started i can cut it off and it will start fine. during this cycle to start the motor will hit/miss (sound like hit/miss is from the pass side of engine) acouple of times and then a big puff of smoke and then it runs fine. i have changed the glow plugs and checked the relay, i also changed the fuel filter and same thing going on. i thought that fuel might be leaking back to the tank, so i warmed engine and then shut engine off and clamped the rubber line that feeds the mechanical pump and that didn't help, next day, same long start cycle. i replaced all the o-rings clamps hoses ect. on the injectors. i have fuel leaking between the bellhousing and motor. i used about three cans of brake-kleen and presure washed the intake and rear of motor and there is no fuel on intake or back of motor, but is still seeps out of bellhousing / rear of motor. when i pull an enclosed trailer, there is fuel spots on the front of the trailer

Snotzalot · 06-24-2007, 12:54 PM

It sounds like your pump is leaking and running down the valley pan.

dvtech · 06-24-2007, 01:42 PM

Check the vacuum sw. on the r. side of the fuel filter resevoir for internally leaking. The sw. looks just like a oil sending sw. You may also remove the fuel filter & look in the bottom of the resevoir for any small pit marks where dirt & water settle. I have replaced many of these for the customer not draining the resevoir often enough & the water & dirt corrodes the aluminum causing small pits. It is a costly mistake. The whole resevoir comes w/ the assy's attached but is high in cost. Hopefully its only the sw. One other thing to check is the h/p fuel feed line on the pass. side of eng. down in the valley. The line is attached to a hold down clamp on one of the bottom intake studded bolts. It will rub a hole in the line & get worse over time. Just did one the other day but it was very obvious. Was leaking real bad. You can see the clamp easier if you remove the upper intake y-pipe assy. Then look down on the L. side in the back where the line travels to the rear port fitting to the head. These fuel leaks are caused from the new low sulfer fuel. [img]/ubbthreads/images/graemlins/warmsmile.gif[/img]

Mr_Roboto · 06-24-2007, 03:23 PM

What brand of glow plugs did you use? How long are the glow plugs running for before they start cycling?

You can eliminate the glow plugs as a problem by plugging in the block heater overnight. If starting improves, the problem is likely glow plugs not working properly.

ddwwmm · 06-26-2007, 11:38 AM

i had two choices at oreilly auto parts i think they were autolite and motorcraft, i put what ever came factory, don't remember which one, but that didn't change anything, i tried the block heater before and after i changed the glowplugs and that didn't help. i am leaning towards the fuel leaking and going down the valley pan where i can't see it, the top of engine is still dry from where i cleaned it. do you know what is involved with changing the intake / vally pan -gaskets? does the injection pump have to come off and how is it "timmed" with what ever it is timmed with.

ddwwmm · 06-26-2007, 11:51 AM

is it possible to leak between the intake and valley pan? the top of engine is still dry from cleaning

ddwwmm · 06-26-2007, 11:58 AM

if this switch is bad, would it cause fuel to leak between the bellhousing and engine? all of the hp lines are dry and no visable leaks on top of the intake. can the pump leak out of sight and be leaking into the valley pan? need information on changing the valley pan / intake....does the injector pump have to come off, and if so how is it timmed and what is it timmed to

cdnsarguy · 06-27-2007, 12:08 AM

Let's not panick......you cleaned off the VPan, you see no fuel leaks from the IP underside right.(check with a paper towel or some light cardboard for wet spots) Now if the crossover return line on top of the rear of the engine near the CDR and GP controller has a leak, any fuel leaking onto the rear of the VP will drain down the square drain hole by the CDR. The fuel will then seep into the bell housing and down from there. If the rear return line to the tank is loose/bad/leaking that could be the problem area too.

Also check the water drain on your fuel filter to ensure it is closed.... it will cause considerable fuel to fly back towards the rear right of the engine and beyond........don't ask me how I know.