Archived help wont start(95 12 valve)

[TLoggains]

wouldnt start this am so changed the fuel filter, checked the heater screen. lift pump wouldnt pump manually, finger fell off. turned the engine over a little ,tried again. other finger fell off. put a little gas on a rag and held in the intake hose. started but wouldnt stay running. little plastic hose called air control hose from the top of the shutoff solenoid to the side of the head looks roughed up could this keep it from starting? fuel solenoid is actuating.

 

[Joe G.]

It's most likely that you have an air leak. Bad fuel hoses are the most likely problem. Other things can also cause an air leak. If the hoses are not the problem then you may have a bad fuel heater. There has been a lot about this problem on the 12 valve forum so search there for a lot of info.

 

[TLoggains]

checked the fuel hoses, looked ok. went ahead and pulled the starter and lift pump. has a fleetguard sticker on top asume it to be orig. 251,000 mi unit will try the bucket test. news at 11:00. if I get it running again will I upgrade from a greenie?

 

[Underwood Tire]

the fuel lines we have troube with are the returns at the rear of the block on the driverside that run down the firewall.

also be sure to check the shutoff solenoid



p. s. even though they may look good it is not a good indication that they ok

 

[TLoggains]

more testing 12 valve wont start

ok put the pump in a bucket of water and actuated it by hand. squirted me in my eye, no problem. was squirting good. put it back on and by-passed the tank lines by going to a bucket of diesel. once it was bled. and started with gas on a rag would run at a fast idle then normal idle for a while , then die in a minute or two. should the air bleed screw really squirt like mad if left open and engine started with gas on a rag? someone said something about the return lines to the tank. would this let air into the system? mine dont look so good. replaced the line between the lift pump and the heater also. what now the heater has a leak maybe?

 

[bmoeller]

Look in my Reader rigs gallery. I have pics of my return line. It looked OK from just a casual glance. After I pulled it off to replace it, you can see the long crack in the line. The supply line is also prone to cracking. They can leak air and not fuel.



Have heard the grommet on the fuel heater connector can leak air and sometimes fuel when it gets bad.



Have you checked the fuel pressure? Could be a bad overflow valve also.

 

[TLoggains]

up and running

thank you guys so much for your help. it turned out to be a faulty lift pump. the good thing is I wont have to replace every rubber hose from front to the tank. return line or heater to pump. got the lift pump from a all nite kenworth dealer for 180. 56. I sure didnt want to believe that it was the pump. as a plus note it idles a little higher. and seems to have a little better throttle response too. once again thanks to all who posted.

 

[MLee]

was the Heater hose/pump hose replaced with a longer one? It has been stated that a longer one is needed. Just wondering, this has keeped me from doing mine even though I am not experiencing any problem at the time, just milage on the old one and am seaking a little more quite.

Can the heater be by-passed temporally?

Marv.

 

[TLoggains]

fuel heater hose

tried to use a piece of regular hose and it kinked due to the tight bend. tried to find a prebent one in the hose section at the parts store. ended up using a heater core hose from gates. hope the diesel doesnt eat it up.

 

[darom]

Guys, I have the similar problem - when my 94 12V sits for a few weeks it is hard to start it without priming the heck ouf of it with the knob. I talked to my diesel instructor and he suggested putting one way ball valves both on the lift pump fuel line and return line to prevent 1. fuel drain and 2. intruduction of possible air.



One way ball valves are cheap. Has anyone tried them? Is it worth it? Is it common for a 2nd gen that sits for some time to be hard to start?



Thanks,

Denis

 

[wcjp]

The fuel lines will let air in without leaking fuel. Only after taking mine off the vehicle were the cracks in the lines identifiable. Also, my biggest problem was the liftpump hose. It had very serious crack. I didn't have time for the dealer to order it. I bought a longer than needed piece and put a big loop in the hose. I used marine grade diesel line. I don't know anything about standard heater hose.

 

[TLoggains]

update.. wont start

do yourself a favor order the 12 dollar hose from the pump to heater. my gates hose collasped pulling up a mountain loaded w/ gooseneck and tractor, brushog. was all the way down to 1st gear and loosing power with traffic backed up. when it died had to back into ditch to keep from running over two kids in a geo. when I lost the vaccum from brakes. all good now. cept for some gooseneck taillights.