SmokenRam

My truck has been sitting for 3days, I jump in to start it. Crank, Crank, Crank, It tried to start a few times, But ketp dieing. Then it start and was missing out like crazy, Then it finally cleared up and was fine the rest of the night. I let it sit for 24hrs. and it did the same thing. What going on here?? I looked for fuel leaks and didn't see any. but even a pin hole could cause this i guess. Could my pump be going bad??? BTW it a 1998 12v. The pump's got 4gsk and d/valves. Thanks Chris

John Faughn

A couple things occure to me , a crack in the fuel line , between tank & pump , thats vacume so you may not see a leak .
Next is the fuel shut off soliniod , going out of adjustment , or the relay conntacts getting burnt- I filed mine a year ago , fine since .

kd460

The spittin and sputterin sounds like it is losing prime to me, and like John mentioned, the fuel lines are probably the cause. Do a search on fuel lines and you will be good to go. It's two short sections of rubber hose, one is 5/16ths and the other is 3/8ths (thats the id of the rubber hose). About 18 inches long for each (buy extra to be safe). The biggest problem with changing out the lines is getting to them.

They are kind of tough to get at, but can be done. Your search will tell you where they are located but briefly they are on the drivers side of the engine, towards the rear, then they drop down along the bell housing of the transmission where they connect to two short pieces of pipe. Then the fuel line continues towards the fuel tank connecting to some braided line, then then it goes to the metal fuel lines along the frame.

There could be other causes for it losing prime, but this is the most common.

Hey John, tell me a little more about the solenoid relay contacts. Where did you cut into or did you dissassemble the relay? I have a new one coming, but would like to clean this one up if possible for a spare. Thanks, KD

SmokenRam

The rubber hose your talking about is the one that runs along side the fuel filter right?? I just replaced it about a year ago. Thats going to be the first thing i check this weekend when i look into it. I just didn't know if there is anything else i need to check. it sounds to me like its loosing prime, but to do that, is it a line infront or behind the pump. Or is there some type of valve inside the pump that could be bad??? I don't know, just wanted some sugestions on where to start looking, and where to go from there. Thanks Chris

SmokenRam

The soliniod, That should come "up" as soon as i turn on the key right?? If working properly??

John Faughn

The hose that goes to the tank , goes behind the head and over the trans down to the tank , the solinoid should go up when the key is in the on position , the loseing prime is what I thought I had going on , the relay that pulls the solinod on is a 70 amp and the points were getting burned and did not always make conntact , so I opened up the box and use a ingnition file to clean up the points , this may or may not be your problum , theres also an adjustment for the solinoid linkage , do a search here to find proceedure.
or maybe someone can link you to it .

infidel

No, it is energized to pull up by the starter, the engine must crank for it to initially pull up. After it is up the key in the on position continues to hold it up.

Doesn't sound like your problem anyway, seems more like an air leak.
If you used gasser hose a year ago it may already be bad. Many autoparts guys will tell you gasser hose is alright to use when in fact it rarely lasts even a year.

You can also have air leaks in the metal lines above the bell housing, the fuel heater and the line from it to the lift pump, the rubber lines at the tank or at the fuel filter.
I usually isolate it by pressurizing the the fuel tank with compressed air from the tank fill, 10psi max, looking and listening for the leak.

Return line in red

SmokenRam

Well i got some good news, I think!! My buddy was trying to start it while i was looking, and i seen some fuel dripping at the fuel filter. So if there is fuel leaking, Hopefully it will be easier to find than just an air leak!! I'm going to look into it tonight.-Chris

wcjp

There are orings in the liftpump that eventually fail. The orings are easily replaced. When taking apart the liftpump be careful. It's all plastic. On my 96' the biggest problem was the soft line from the fuel preheater to liftpump. After replacement I opened the line. Couldn't believe the dryrot. Never leaked fuel out but, air found it's way in. If replacing the fuel supply/return lines now is a good time to do the starter contacts. Removing the front driveshaft and starter makes the job alot easier. Getting the starter out is the hardest part for changing the contacts. Do the contacts now. I also had a minor air issue with the fuel preheater screen and gaskets. Use diesel rated Coast Guard approved fuel line. Starter contacts can be sourced from a variety of places.

I ordered my starter contacts from:

http://www.fostertruck.com/dodge/


Dodge tech info:
http://dodgeram.org/support_pgs/diesel_ix.htm

kd460

In the diagram that infidel provides, the red line is the "feed line". You also have a return line that is near the feed line. The feed line (going to the pump) is 3/8 inch. The return line is 5/16ths. Both should be replaced. Also the runner hose that is short and curved-it connects the lift pump with the fuel heater/prefilter. That can leak air as well. (like wcjp desribed).

The leak at the fuel filter is probably one of two things. The water in fuel sensor (which is plastic and is known to crack), or the fuel filter drain valve. They have rubber O rings that can dry out and leak as well. It can be taken apart and the O-rings replaced.

If its the water in fuel sensor, be careful as it is plastic and can crack easily. A replacement if you can find it is about 50 plus bucks. I made a new one out of a brass brake line fitting and some JB weld for about $8 bucks. Looks stock and will never break or leak. Good luck, KD

Teddy Bear

I have the exact same problem with my truck. Sometimes it starts great but if you let it sit for a while, sometimes it takes forever to start. You can hold the throttle wide open and itll turn about 1500 at the most and whitesmoke,pop,crackle, etc. and then all the sudden it just clears up and it runs perfect. It doesnt do it all the time, just sometimes. I think im gonna change my fuel filter soon to see if that helps. If not, i guess i'll check the lines too.

kd460

If your lines have not been changed then you need to. My 97 has had the lines changed 2 times, and after I finish my coffee, I'm gonna do the 3rd change out. I do run biodiesel as it is harder on the fuel lines.

This time I am eliminating the braided section of hose that connects to the hard lines along the frame. I'm running rubber hose from the frame up to the hard metal lines on the engine that have the banjos on them.

I tried to find barbed banjos to even eliminate those hard lines, but no luck yet. I even thought about using something like this to eliminate the banjos:

http://www.vulcanperformance.com/ser...2%84%A2/Detail

Only problem is they do not fit our 12 valve engines/pumps. We need 14mm and these are 12mm. I have had no luck finding the 14mm yet. Plus, might be a clearance issue for the return line on the pump (need 90*?).

Infidel has reccomended just abandoning the lines completely (including the hard lines along the frame). Not sure how the connection is made at the tank with the replacement rubber hose. My hard lines are in good shape, so I'm just changing out the rubber portions. I beleieve there is a plastic section of hose near the tank. KD

infidel

No, the red line is the 5/16" return line. The 3/8" feed line isn't in the picture as the rubber portion ends off the far right side of the diagram.

SmokenRam

Well guys, it was as simple as the gasket on the fuel fiter was leaking. changed filter and gasket, and good to go.

kd460

Yep, that is the return line-my mistake, I should know better...

Just got done changing mine out. The old rubber hose was fine. No cracks, no leaks, nothing wrong with the fuel lines at all. I did remove the section of braided hose, the short section of metal tubing by the tranny and flaired the metal lines at the frame to accept the new rubber hose.

The new rubber hose starts at the frame and runs to the normal connections up by the engine.

I also took my fuel solenoid relay apart and the contacts in the relay were nasty. So that is what probably caused my occasional difficult to start condition. Cleaned up the contcts, put the relay back together and it starts fast.

New fuel filter and life is good. I am surpized at how well the the fuel lines looked considering the amount of bio I run thru them. KD