Engine/Transmission (1994 - 1998) Troubleshooting help - VERY difficult cold starts

[Tom Trujillo]

Suddenly its become very difficult to get my '97 started. I mean very difficult, even in temps in the 50's. Today in the 30's and 40's I gave up. As a curiousity, I just plugged it in to see if it will startup easily later tonight or in the morning.



Any suggestions as to what to look for? Except for a prime-loc and header its bone stock under the hood.



Thanks in advance.



Tom

 

[EKlem]

When you say that it is very difficult to start, does it crank quickly or slowly. If it is not cranking fast enough, it could well be your batteries or corroded connections.



If the truck is cranking normally, it could very likely be your grid heaters. Make sure that your batteries are charged, then turn the key to the on position. Watch the voltmeter and if it is down near 8-10 volts, your grids are running, if it is near 12-13 volts, your grids are not running. The usual cause of this is that the relay has stopped working. If the wait to start light is going out immediately, it is also possible that it is your intake air temperature sensor.



If the grids are working and the engine cranks quickly, the next thing to check is fuel. A common problem is that the fuel system develops an air leak either in the fuel lines or fuel heater. Any air in there will make the truck crank for a while before firing. It may also require throttle to fire. If it fires with a little throttle, also check your idle speed, it may be too low. The final thing to check would be your shutdown solenoid. When you turn the key on and bump the starter, it should pull up and stay there until the key is turned off. The solenoid is on the back end of the injection pump.



A little more info would be helpful in diagnosing it. Good luck getting her running again.

 

[KYOUNG]

Yea, check your shutdown solenoid and make sure the rubber boot hasnt decinagrated and sticking in the spring... makes it difficult to open!!

 

[JoshPeters]

I just worked on a truck over the weekend with similar issues. The idle was WAY low and the timing had slipped. I'd check those things.



JP

 

[Signal73]

I also checked out a truck on friday with similar issues, turn your key to the run position and pull up on the shutoff solenoid arm then try to start it. If it starts normal your shutoff solenoid is toast... .

 

[Signal73]

here is pic with shutoff solenoid shown:

#ad

 

[Vaughn MacKenzie]

If the truck is cranking normally, it could very likely be your grid heaters. . . .

I'm pretty sure the grid heaters aren't the problem. One winter when my grid heaters weren't working on my '96 for a week lit off instantly on cold mornings. The truck sat outside unplugged with temps down to about 20F.



Tom with a few more details we should be able to help ya out here. It's more likely a fuel problem like EKlem described.



Vaughn

 

[Tom Trujillo]

Thanks for the ideas. Here are some responses, note, I am mechanically challenged beyond the obvious.



1. This problem started about three weeks ago when temps were still in the 50's and 60's.

2. I put a new fleetgaurd filter (prime-loc) this Sunday and did notice that there appeared to be a little fuel tear drop between the filter gauge and the head where the filter screws into. I replaced the o-rings on the gauge today but it appears that there is a thin plate between the gauge and the head and thats where the drop is coming from. Tomorrow I have to call these guys at Prime Loc to see if there is a gasket or something behind that plate. I cannot say whether its coincidental or something thats been there several weeks back to when the issue began.

3. Wait to start light takes a while, normal I would say, to come off given the colder weather. 5 - 10 seconds.

4. I jsut started up the truck after having the truck plugged in for about an hour and a half and it started (though very rough running) after the second 5 second burst of cranking. I had to hold my foot on the throttle to get it going for a while.

5. Voltage is at about 10-12 when I try to start it up, and, after its running, so it appears the grids are working.



any other thoughts?

 

[EKlem]

From the information that you have given, I would guess that you indeed have a fuel system problem and it is that you have air getting into your fuel system. Air in the system causes longer cranking times and rough running until the air is purged out.



I am not familiar with the prime-loc filter setup so I am not clear as to where you are seeing fuel. Anytime that fuel is leaking out, air can get in. A lot of people experience troubles when the leaks are so small so that fuel cannot leak out so if you in fact have fuel leaking out, I would definitely start by trying to stop that. Hopefully someone else with a prime-loc can chime in on this.



Also be aware that anytime you open up part of the fuel system, air will be introduced and it will take a lot more cranking to get the truck started again. If you introduce a lot of air, you can use the primer bulb on the lift pump to get it out.

 

[dtygart]

I am not sure you can get Primeloc parts anymore. If not, take the "O" rings to your parts store for matching ones. Did you lube the filter gasket with a finger wipe of diesel? Is the filter tightened 3/4 or one turn whatever the filter says? Good luck, wish we were closer so I could help

david

 

[Steve St.Laurent]

Are you sure that you got the o-ring off with the old filter? I've seen it more than once (many times more) that an o-ring on a spin on filter stays stuck to the head and when you put the new filter on you have two o-rings on there which always leak some.

 

[JoshPeters]

If you cranked it for 5 seconds with it plugged in and it started... rough but started... I'd be checking timing. A drain back fuel problem would either be an extended crank, or start and run for about 20-30 sec and die, then hard restart.



JP

 

[BIG C]

Youve got air in the fuel system somewhere. Now the fun part is finding out where. Many times the leak is not big enough to let fuel out but is small enough to suck air through. Make sure all fuel system connections are tight starting with your fuel filter. Good suggestion on the doubled up oring. The original usually gets stuck on the the threads where the filter threads on to.



Good Luck!



Chad

 

[Howard Durand]

If this started before you installed the Prime Lock, I doubt if that is the problem. The most common cause for this type of trouble is ageing hoses in the fuel system. There's two of them, one that delivers fuel to the lift pump and one that returns overflow fuel from the injector pump. They start cracking and breaking down with age and when that happens they need to be replaced.

 

[JoshPeters]

4. I jsut started up the truck after having the truck plugged in for about an hour and a half and it started (though very rough running) after the second 5 second burst of cranking. I had to hold my foot on the throttle to get it going for a while.

If there was an air leak the 5 second crank time would not be sufficent guys.



It would crank for probably almost a minute if it was an air leak.



JP

 

[surfbeetle]

Don't forget to check the rubber fuel lines that go from the frame to the engine. Mine just started doing that again and this time I ordered the replacements from LarryB's. This will be the fourth and hopefully last time I have to do that job. It's a PITA.

 

[Partyat33]

I would hate to disagree with someone with over 5000 posts, but my truck will not start below 40 degrees without grid heaters.

 

[KWentling]

Another place to look is the electrical connection at the fuel heater. When I was looking for an air leak, that's what I found after changing hoses. The length of crank time untill starting would depend on the size of the air leak. Need to get the Prime Lock leak fixed first. My truck starts fine down to 30, probably lower, without waiting for the grid heaters.



Kim

 

[Tom Trujillo]

Well looks like the problem is solved. Spent the better part of the day yesterday screwing around with the different o-rings (three sets) on the Prime-Loc filter and gauge system and never got it to stop weeping fuel.



Seems as soon as I screwed the gauge back on, it would pull apart the two plates between the base where the filter screws into and the gauge itself, therefore, the weeping. Its a little wierd as the gauge has been on there for two years w/o a problem (or leaks).



Bill at Ashland Diesel is going to send me a new updated base that does not require the intermediate plates so that should solve the problem. In the interim, two 1/8 pipe plugs into the base solved the leak. Considering the prime loc on the truck is 5 years old and the gauge setup is over two, Bill and Ashland have my future biz as they just said they would not charge for the new plate etc. - Pretty Cool -



It seems to have helped because the truck has started just fine over the past two nights and mornings with temps in the 30's overnight.



Thanks for the help.



Tom