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Junior Member
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Discussion Starter #1
Hi all,

I have a type III ambulance that I use for a work truck. it is a 1990 e350 with a 7.3 box type truck.

I have only driving it a few times this winter. the other day I went to start it.. it ran for about 10 seconds and died. cranked and cranked and it started up and ran fine..

this morning, did the same thing. starts for about 10 secs, then died.. this time I was unable to start it (drained batterys)

this truck has 70 thousand miles on it and has been regularly maintained when it was in server as an ambulance. Where should I look first. this is my first ford diesel, or my first diesel ever!

thanks
mark
 

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73 Posts
Prob time to replace the batteries. Get them tested and properly charged before you do anything. Sitting around for long periods of time never helps either. Run that bad boy.
 

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Discussion Starter #3 (Edited)
no start

no, its not the batteries. they are less than a year old, interstate police interceptor batteries and theres a special dual battery system monitor on the ambulance that keeps them charged fully charged...but ty..

let me rephrase..

first time starting the other morning, ran for 10 seconds, died.. I then cranked and cranked, and it eventually started, and drove it all over town with a few stops. started up ok at the stops. a few days later. I come out on morning, started it, ran for 5-10 secs, then died.. tried to restart it a few times with no luck. after a few more times trying to start the batterys were getting weak so I stopped.
 

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You are getting air in the fuel system,possible causes:eek:-rings on injector return line caps;replace lines,caps and o-rings(usually comes as a kit),fuel lift pump,fuel line from filter to injector pump seals,if the truck is equipped with dual tanks then the o-rings in the fuel lines at the tank and/or selector valve,injector pump.Most common is the return line o-rings at the injector and the fuel line from the filter to the injector pump seal.

bronco1
 

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Discussion Starter #5
not starting

but why is this only happening at cold starts, the truck runs fine when warm.
i suspected glow plugs. ty
 

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First off,if it was glow plugs,the truck would not start.You say the truck starts fine then stalls after it runs a few seconds,so the glow plugs are working.The reason that it stalls after a few seconds is that the fuel in the injector pump and maybe the supply line to the inj pump is used up and then you get a gulp of air.The reason that this only happens after sitting a longer period of time is that the leak is small and is drawn into the line as the fuel in the return line back to the tank doesn't produce a high rate of vac in the line-weght of the fuel in the line(no,the fuel in the return line dosen't drain out normally in a sealed system).During the day after running the vehicle the leak is small enough that there is't enough air in the fuel system to cause a stall.If there is enough air in the system during the day,it may only cause a slight stumble after starting until the leak get bad enough to cause stalling during the day.If you have any fuel leaks on the engine,repair those first.

bronco1
 

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Discussion Starter #7
not starting

Ok ty for explaining it. Also I wanted to point out,, i did an oil change before all this starting happening . i changed with rotella 15-40 .. but i dont think that should cause an issue..
 

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Discussion Starter #8
no start

well today i cannot get a thing outta it. I have alittle experiance in gasoline engines.

what things can I test for? I imagine I can open the shrader valve on the fuel filter housing and see if fuel squirts out to see if its getting fuel.

does the fuel pump work like this? when u turn the key, it pressurizes the fuel system then stops once its pressurized till its started?


also i also read somewhere if u get air into the oil system it wont start is this true.. it seems it started doing this after i changed the oil. thanks for the replys on my "bambulance"
 

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1990 is an IDI diesel,so you have to crank the engine to do a fuel pressure test as it has a mechanical pump.This engine also dosn't have a high pressure oil system to get air into.

bronco1
 

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Discussion Starter #11
not starting

Ok,, its still not starting. when i crank it, theres two lights that light up outta four(the glow plug light,engine temp, water in fuel,check engine)

while cranking the engine temp light and water in fuel light is on. but when you release the key the lights go out.

this ambulance hasnt ran in a month and been sitting.. any suggestions?

mark
 

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- Moved to correct forum for better responses.

Yes, this is an "IDI" and not a Power Stroke engine.

Your problem is NOT batteries or Glow Plugs but fuel pressure.

On each injector, under where the fuel line connects are fuel spill caps with hoses connecting one injector to another then returning the "spill" to the tank. When the o-rings under these caps get old, dry hard or split, they leak air. This allows the fuel to siphon back into the tank so after the engine has been off for an extended period it becomes very difficult to start.

You may, or may not, have an electric supply pump because the Ambulance chassis could have that option due to the single aft-of-axle tank. If the lower right side of the engine has a fuel pump on it that is connected to a hose and line, then you DO NOT have the electric - which is good because it makes the diagnosys easier.

The worse the o-rings on the fuel spill caps get, the harder the engine is to start and the more rapidly the fuel siphons back to the tank. When they are really bad, you can even get a massive fuel leak pooling in the valley under the intake.

Look at each fuel injector, where these caps are and if you see ANY fuel wetness, go to Ford or IH and get the o-ring kit for the injectors. If it were me, I would also replace the spill caps, hoses and clamps while I have them off.
 

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Discussion Starter #13
not starting

Okay i will go out in awhile and begin diagnosing. So its normal for the water in fuel light to be on while cranking? I cant remember if Ive ever seen it on before.
thank you for your help.
mark
 

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Discussion Starter #14
it seems i do have a fuel pump

Okay I was just underneath it today and didnt see any thing attached to the motor like you were describing. It seems I have a wire harness going to the tank with 3 wires, which go into the top of the tank (glad iam a small person as i almost got stuck underneath the axle) . would there be a fuse for this somewhere? would the fuel pump run all the time with the ignition on? if so I could crawl back underneath and listen for it. how can i tell if the pump is working? Thanks for the replies.

mark
 

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Ground
Pump Power
Fuel Level

When you first turn the key on, there should be a buzzing noise from the tank indicating the fuel pump is running, 5-15 seconds is all unless the engine is running.

You can remove the fuel line from the filter, turn the key on and see if you get any fuel. Then crank and see, if none with key on but some during cranking, you might have missed the fuel pump on the engine - they can be harad to find, see attached photo from a pickup.
 

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Discussion Starter #16
finally started

well since this nice weather ive started to work on the ambulance. finally got it started (took it along time cranking in 20 sec intervals) , ran it for awhile.


noticed fuel dripping onto the driveway,, seems to be coming up top somewhere. Tommorrow, when its cooled down I will remove the "hood" inside the truck to see where its coming from.. I imagine it is a injector o ring leaking. I will be searching forums for a good "how to" guide to replace the injector Orings. can somewon point me to a good one if they know of one. it will take a bit of effort to get the hood out, as either the seat is in the way, or the ambulance switch console blocks it too from coming out (more switches than a 747 overhead console :) . I have basic skills, i have replaced fuel injectors before on a 87 buick grand national so I hope this is the same skill level to do this. Thanks alot to all who have helped me.

Mark
 

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Discussion Starter #17
update

after several weeks of sitting the ambulance is on the road. it was a plugged fuel filter with the intake hose leaking, then after those replacements, the fuel hose blew that runs behind the motor to the other side. so i spent all these nice days the east coast is having replacing all the fuel hoses between the injectors.
why i have this apart, i noticed a broken cable that looks like a tv cable on a transmission near the throttle body or injection pump. i traced the cable and it runs underneath the dash. it runs good and shifts fine. and the speedo works. so iam sure its not a transmission cable or anything. the trans shifts good but I dont think its shifting into OD on the highway.. this ambulance only has 74k miles.. any ideas?
 

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High idle cable/manual throttle ;)
 
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