My truck has started to be harder to start within the last few days, and i don't quite know what it is. I replaced the fuel filter last night and still it's kinda hard to start. I installed my POD's in the winter and it was always harder to start in the winter, so i can't really tell if that made a difference. Anyone else notice that the POD's make it a little harder to start? It could also be that i dumped a VERY healthy dose of additive in the tank about a week ago, but i wouldn't think it would make it harder to start. Would a tired injector pump or lift pump cause this?
Weak starter or battery maybe?

BTW, i was just wondering how much our fuel tanks hold, since my fuel gauge doesn't work i fill up quite regularly. Also what kinda mileage can you guys get from the tank?


thanks

Jeff

 

When my lift pump started to go it got harder to start when left for more than a few hours. It would lose prime and so the engine would have to crank a fair bit to build the pressure back up before it would start.


As a test try pumping the maunal primer on the lift pump a couple dozen times before firing it up in the morning. If it starts easier its likely its the lift pump.

 

Harder to start meaning it cranks more revolutions before firing, or turns over slower? More cranking sounds like a lack of fuel. Could be a fuel supply or return line is letting air into the system somewhere. If it's turning over slower, poor connections may be to blame.

 

It don't turn over slower, just takes more cranks. When i push the lever on the lift pump it feels VERY VERY easy to push down. Is this right or can you usually feel the diaphram pumping? I'm sure it's because of lack of fuel, i hope i don't have to go searching for a air leak

 

The lift pump runs off the cam, I believe, so you may have to bump the motor over to get the lobe where it needs to be for the manual lever to function. Had this experience over the weekend whenI froze up and had to prime everything

 

When my lift pump was going it was really easy to push as well. Can you put a gauge on it and check the pressure?

 

If theres a shadow of a doubt get a new L/P, if its bad it will take out the I/P soon after. Your IP if fuel lubricated as you know and it will get damaged.When was the last fuel filter change? You can get one from one of the vendors here for under $50 bucks or so. Regarding fuel mileage: should have a 30 gallon tank, the low fuel in mine came on around 7 gallons left. Dont know what your pullin for mpg`s but you can calc it.

 

A bit of a correction if I may.....the VE pump has a "supply side" vane pump which is designed to actually pull it's own fuel...depending on the "head" of course.
Other's as well as myself have found that our lift pump was calfing on us (reading near or on zero psi) at or near WOT yet the truck continues to run fairly well.
It may be that the lift pump is pretty well shot entirely and the supply side vane pump has to do the work, which is causing the "extra cranking" condtion but I'd look elsewere first.
Fuel filter first, then fuel line(s).
Check them for cracking or porosity which can let air in or allow partial drainback which forces the lift pump and VE to need extra cranking to refill.
The POD injectors also seem to result in slightly lower idle RPM too.... did you tweak your RPM up when you did the install??? It should be about 750-800 RPM in "D" and with AC on MAX...
Setting the idle up as above will help to keep a smoother idle and also to keep oil pressure up when loaded and/or in hot weather....

You may also need to run some conditioner thru the system. Get yourself some fuel condtioner with a good detergent package and perhaps cetane improver. Double the recommended dosage on the first full tank of fuel then go to the "recommended" dosage on the second fill up.
That will help clean out any deposits in the entire system.

As already noted, our pumps are lubed and cooled solely by fuel so keep it clean and use an additive as often as possible. OH...cold weather will result in fuel gelling AND a poorer idle quality due to the shift to "winterized fuel". It is not as good a fuel period.

pb....

 

I have just replaced the fuel filter and still it does the same thing. I run conditioner through the thing on a regular basis. Do the lines between the fuel tank and lift pump usually hold up well? should i just look at the lines after the lift pump? I'm sure i'd notice fuel leaking if the lines were shot.

I cranked my truck over so the lift pump lever works now. I am going to give that a few cranks tommrow morning and see if it fires right away. I have a feeling that it could be the lift pump.

For now would it be best for it not to run WOT?

 

Sammy340,
My dad's 90 was doing the same thing.
Try unhooking the supply line from the tank to the lift pump and connect a 3 or 4ft piece of clear hose to it. Then put the other end in a 5g can (under truck) full of diesel. Prime and bleed everything and try starting it. Let it run for a while then shut it off. Let it set for several minutes, or an hour or so. Then before you start it check the clear line to see if the fuel is being held up in the line. If it is then it's the supply line from the tank, or in my case a O ring on the bottom of the pickup assembly in the tank. Yep it was a .10 O ring that gave me all that grief. If the fuel is not being held up in the clear line, it's probably the lift pump, or some type of leak between the lift pump and the injector pump allowing the fuel to run back down. Good luck......

 

Ram350

Thanks

I am definately going to do this tommrow and see where the problem is. That's a good idea to locate the problem. I have a feeling it is indeed the lift pump. I have two fuel filters on my truck, a aftermarket one and the stock one. How the hoses are is that the pickup line from the tank goes to a primary (aftermarket) filter, which sits at the same level as the stock fuel filter, then from here it goes to the lift pump, and then to the stock fuel filter. If the lift pump was bad, it wouldn't able to force the fuel back to the tank, since the primary filter is above the lift pump. So could it still be the lift pump?

Also, is this really hard on my truck runing it like this? I don't drive allot but if it's hard on it i wonna just park it till i get it sorted out.


thanks again

jeff

 

You're not hurting anything except maybe the starter. The lift pump is cheap and easy to change, but I'd follow up on Ram350's suggestion. A little bit of an air leak on the suction side can cause a lot of problems like what you're having.

 

Today i did as ram350 instructed me to do, i took the suction line off the lift pump and put it into a bucket of diesel and fired it up. I then shut it off after 5 minutes and looked through the clear line for about 15 minutes and the lift pump DID hold prime. I then fired it up with fuel still in the suction line of the lift pump and it was still hard to start. So i take it that my lift pump is ok if it held prime? I checked my return lines today as well and there seems to be no leaks at all. Would a worn out injection pump cause this? Fuel filter has also just been replaced.

Any sugestions?

thanks

Jeff

 

The lift pump could be down on output flow/pressure and still hold prime. I'd replace it. Sounds like your fuel lines aren't the problem though.

 

I didn't notice a problem when my lift pump went, but in mine the diaphragm got a hole, and it was shooting diesel out of the vent hole. When my friend's went he did get the symptoms you got with the hard starting.

I'd do the lift pump as well. You don't want to stress out anything else because the lift pump is not doing it's part.