Have to pre-heat even above 40 degrees to start

[rowbotham]

My service truck, a 98 12 valve won't start without pre-heating unless the engine is warm. It's just come out of a fuel injector shop where they removed the pump and set it up on a test bench. They put the pump back in, set the timing at 16 degrees and the truck runs much better but won't start without the pre-heat. I have a 96 also and it starts down to 10 degrees or so without heating. So whats up with this engine? Fuel filters, return line have been replaced. Once it starts it will idle ok, smokes a little till it warms up wich is normal. The shop said to try giving it a little throttle when cranking to set the rack but that just makes it smoke when it starts after I wind up pre-heating it. Whats up guys?

 

[Missouri Mule]

rowbotham,
Your intake heaters are supposed to come on below 59 degrees.

After your heaters go off is the engine easy to start or is hard to start?
If it fires up right away I wouldn't worry about it. (after pre-heat)
But if it is hard to start and acts like a no fuel situation I would check fuel return valve, lift pump (One of the check valves mite be bad and letting fuel bleed back to tank. ), maybe even the pre filter in tank or fuel filter leaking at gasket.

In your post you state "unless is warm" this leads me to believe the fuel is bleeding back to tank either supply line or return line. They should of checked injector pump while on the bench for bleed down

Also is your 96 and 98 parked in same location.

------------------
Bill Thomas
Missouri Mule - 96 Wht 4X4 ST CC,5 spd, 3. 54, 8 ft bed, 1 ft high cheater boards.
99 Freightliner bl/wht FL60 ISB-5. 9 24v,215 hp,520 tq,6 spd, 3. 59 nsr,16 ft box, 19. 5 tires,Wt/gvw 11,000/23000

 

[rowbotham]

Originally posted by Missouri Mule:
rowbotham,
Your intake heaters are supposed to come on below 59 degrees.

After your heaters go off is the engine easy to start or is hard to start?
If it fires up right away I wouldn't worry about it. (after pre-heat)
But if it is hard to start and acts like a no fuel situation I would check fuel return valve, lift pump (One of the check valves mite be bad and letting fuel bleed back to tank. ), maybe even the pre filter in tank or fuel filter leaking at gasket.

In your post you state "unless is warm" this leads me to believe the fuel is bleeding back to tank either supply line or return line. They should of checked injector pump while on the bench for bleed down

Also is your 96 and 98 parked in same location.

I'll have to ask them if they did check for bleed down while it was on the bench and yes both vehicles are parked in the same driveway.
Thanks

 

[Joseph Donnelly]

Why did you want the timing so high? 15-15. 5 should be plenty for almost everyone. I don't know if that is having an effect. Sometimes a supposed 16 ends up somewhere else depending on the shop's carefulness. Do you get white smoke after starting it? If so, timing could be too low-- either set that way or slipped a little if the taper fit wasn't clean enough.
I agree that the fuel return line and overflow valve should be checked--the former for leaks and the latter for pressure.

 

[Missouri Mule]

rowbotham,
Noticed return fuel line was replaced.
Was wondering who repalced it. Independent garage or Dodge under warranty?

If Dodge did it, they mite have put the same cheap fuel hose(rubber) line they had on in first place. If so check return fuel line also.

 

[rowbotham]

I replaced the fuel line myself with a good Gates hose while the pump was out of the way (much easier). I have tried priming the pump before cranking and it makes no difference. Once pre-heated it starts right up with the normal smoke for a cold diesel so I guess I'll just live with it. It makes me wonder why the other Dodge in the driveway starts so easy with no pre-heat!