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so today i hooked up the hydroboost and powersteering and went to start the monster diesel. It had a hard time starting i ended up pouring a little diesel down the intake and she fired right up and ran very sound i ran her for about 3 mins and then shut off for about 10 min while i adjusted something then i went to fire the diesel up and nothing it is cranking over and not starting. Yesterday was teh first time i have ever started it and it kicked over after about 1-2 seconds of cranking now today it will barly start what could it be air in the lines or what please helpe.

Happy new years everyone thanks for all the help
 

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sounds like it losing fuel pressure, use the lever on the side of the mech pump to pressurize it. If you have a leak in any fuel line, including the return line, you can have this happen. bump the starter if the lever doesn't provide any resistance. Mine dose this after a week of not running, i just pump the lever a few times and it starts right up...
 

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I'd suspect a leak-down, too, but there's something else I'd check that's related:

Try taking the fuel filler cap off the filler neck slowly, and listen for any "whoosh" of air going in.

If you're developing vacuum in the tank, it can effectively suck fuel out of the IP at shutdown, and you're not developing enough suction with the IP and Lift Pump at cranking speeds to overcome this and get re-primed with fuel to start initially.

Adding a shot of fuel to the intake might have let it get spinning fast enough to get fuel suction going and keep running, but I'm betting if you'd tried putting any load against it it would have shut down.

May not be it, but it's fairly easy to check.
 

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Discussion Starter #4
I'd suspect a leak-down, too, but there's something else I'd check that's related:

Try taking the fuel filler cap off the filler neck slowly, and listen for any "whoosh" of air going in.

If you're developing vacuum in the tank, it can effectively suck fuel out of the IP at shutdown, and you're not developing enough suction with the IP and Lift Pump at cranking speeds to overcome this and get re-primed with fuel to start initially.

Adding a shot of fuel to the intake might have let it get spinning fast enough to get fuel suction going and keep running, but I'm betting if you'd tried putting any load against it it would have shut down.

May not be it, but it's fairly easy to check.
what do i do if there is a vacuum problem
 

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You would need either a vented gas cap, a vented fuel filler neck or a vented fuel tank. Most American vehicles have some form of factory venting, later models venting to a charcoal cannister.
 

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I ended up pouring a little diesel down the intake
Don't ever do that again. You could hydraulic lock it.

Besides, it could also fire long before TDC. You don't want that, it'll kick back.
 

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Someone on the yahoo Yanmar Tractors board was saying to use propane or a little gasoline on a rag near the intake, but NEVER ether (starting fluid). Never tried any of them.

#2 diesel on a rag wouldn't vaporize.


BAR NONE......these engines start ULTRA easy when everything is RIGHT.

Make everything RIGHT and it will NEVER fail to start, even when pretty damn cold out.

If you have to start adding fuel and crap to the intake air something is WRONG.
 

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I had the little check-ball in the lift pump develop some pitting after the engine had sat in storage for a while. Some nights it would seal up, most other nights it all went back into the tank. Replaced the lift pump and all was

-Scotty
 

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I think FITTY is on the right path. That is one of the most difficult to diagnose. We have run across peanut shells in the fuel tank before too. That was the weirdest. Even though Cummins says it's okay to use ether for starting their engines, I prefer Silicone Spray because it is less volatile.
 

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so today i hooked up the hydroboost and powersteering and went to start the monster diesel. It had a hard time starting i ended up pouring a little diesel down the intake and she fired right up and ran very sound i ran her for about 3 mins and then shut off for about 10 min while i adjusted something then i went to fire the diesel up and nothing it is cranking over and not starting. Yesterday was teh first time i have ever started it and it kicked over after about 1-2 seconds of cranking now today it will barly start what could it be air in the lines or what please helpe.

Happy new years everyone thanks for all the help
Quick Checklist:
1. Do you have a "screen filter sock" on your pick up tube in you fuel tank? If so remove it. Fuel oil will eventually cause it to plug up.
2. Have you recently changed your fuel filter? Water in fuel? Fuel filter plugged up? Fuel filter loose?
3. Loose hose clamp on your fuel line. Have you retightened your hose clamps since you did your install? A kinked hose at a short bend?
4. Kinked return line hose?
5. Dirt in the lift pump check valve causing the lift pump to loose its prime.
6. Crack an injector line loose and check for fuel to the injector. If no fuel..
7. check for power to the shut off solenoid on the injection pump. Intermittent engine ground? Can you hear the solenoid click if you hook a jumper wire to it from the battery? Will it start using this jumper?

I have owned, operated, and been around diesel engines in various equipment since 1970 and I have never heard of anyone pouring fuel oil down the intake to start a cold diesel engine That just doesn't work like pouring a tablespoon of gasoline down a carburetor on a gasoline engine. The only thing that is going to accomplish is popping a head gasket or bending a connecting rod if you pour too much in. Remember diesel engines normally operate off of the timed compression and injection for ignition, not fuel vapors.
 

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Discussion Starter #13
thanks againn for all the replys i checked everything again today and it started after i bleed the system again but then it would not start back up it is starting to sound like the lifter pump i am going to check that tomorrow when it is running it rounds very good idles nice and runs strong i know it was stupid of me to pour diesl in the intake dont know why i did it hope to get it going tomorrow so i can send it to the exhaust shop thanks again for all the input :beer:

I have the fuel solenoid hooked to a switch and cannot hear it click when i turn it off but not on i know that the switch is working for sure because i have started it and used the switch. I does click when i do hook it to the battery for straight connection.
 

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thanks againn for all the replys i checked everything again today and it started after i bleed the system again but then it would not start back up it is starting to sound like the lifter pump i am going to check that tomorrow when it is running it rounds very good idles nice and runs strong i know it was stupid of me to pour diesl in the intake dont know why i did it hope to get it going tomorrow so i can send it to the exhaust shop thanks again for all the input :beer:

I have the fuel solenoid hooked to a switch and cannot hear it click when i turn it off but not on i know that the switch is working for sure because i have started it and used the switch. I does click when i do hook it to the battery for straight connection.
It will click when a jumper wire is hooked up to battery voltage.

Scott
 
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