Hello all,

I have a 1990 ford e350 ambulance with the 7.3 non turbo. its been real hard to start on cold starts. it fires for a few seconds then dies and u have to crank for a long time to get it going. after that it starts and runs fine and starts fine on when its warm. the truck has 75 thousand miles. I changed the fuel filter 5k ago, but iam changing it again tommorrow. today i also changed the glow plugs 7 new motorcraft (the 8th one is a pain and needs the massive alternator removed to get to it) , hoping the new plugs would solve the problem. well it didnt. so i wasted money on glow plugs lol. Also i removed the fuel filter and it was full of fuel. Iam putting a new one on tommorrow, old one had 5k..the truck mainly sits and gets used on the weekend mostly. any suggestions. i dont wanna burn the starter out just trying to start it every weekend.

mark

 

i also checked power at each glow plug, all have good 12 volts..

 

Sounds like air intrusion .
Check the return lines on the injectors , the small lines that connect the injectors together .
9 times out of 10 the lines are brittle and leak . Also the O rings under the plastic caps on the injectors also leak and cause a hard start .
Repair those and any other leaks you find and you should be good to go ....

 

ok ill check that tommorrow, i already put new return lines a few weeks ago on one side. i assume too to check the orings on the injectors i have to take them off? i might as well get new ones then. how do i detect leaks? thanks for the advice.

 

Here is the forum for that engine: Pre-Power Stroke Diesel (7.3L IDI & 6.9L) - Ford Truck Enthusiasts Forums
Go there and read the sticky thread about glow plugs. It sounds like they are not working to me to me. Does the wait to start light come on? How long does it stay on?

 

Basically you're just looking for wet spots on the engine ...

 

yes it comes on and stays on for about 45 secs then goes out, ive put new gp's in and tested the controller and its all good. ill look closer at injector orings tommorrow and put a new fuel filter on (but i just changed it 5k ago if that)

 

Since the condition only happens when the truck is cold, why don't you get a block heater?.

 

well ive never needed one, when i first bought it from a nursing home (i use it to transport atvs and dirtbikes) it started great when it sat, even in the dead of winter all covered in snow without a block heater, and i think there is one but i dont run it. cause it always started great. just up untill a few weeks ago it started doing this and iam finally tired of it and doing something about it and throwing money at it to get it back to like it ran when i bought it.

 

I'm sure it's a air leak into the injection system ..
Check anything that has fuel going through it ..

 

If you are sure the glow pugs are working, I agree that it sounds like air intrusion. 45 seconds is too long, it should be more like 10.
You should already have a block heater, it comes factory in a freeze plug hole behind the starter... look for a cord in that area.

 

Ok, got a new fuel filter, probally wasted money on it since the old one was only 5k miles old. filled with fuel, installed. now the truck will not fire at all. also checked all fuel injectors for leakage and return lines ok. should i throw more money at a new glow plug controller? I hate throwing money at this thing

 

Are you getting white smoke (unburnt fuel) while cranking? 45 seconds of glow plug light is too long, that would burn up your glowplugs. How are you testing them? These things also need to turn over pretty fast to start.

 

idk if theres white smoke. i timed it tonight and it takes 15-20 secs for the light to go out, then the relay clicks 3 times, about 2 secs apart which has always been since i owned the ambulance. i also noticed some smoke coming from the area of the relay, and i have the inside hood out so i can work on the motor sitting in the drivers seat.

 

i might as well throw 50 more bucks and replace the relay lol . but I know something is using alot of juice when i turn the ignition on,as i have a volt and amperage meter on the switch panel used to control lighting. and the volts and amps go way down when the glow plug light is on