Engine/Transmission (1994 - 1998) Why so hard to start after upgrades?

[JGheen]

So been noticing since I installed my EDMs and upped the timing, my truck was hard to start these last couple mornings. Almost like there is air in the fuel lines and no pressure? Kind of have to give it a bit of throttle till it clears up and idles. It doesn't seem to do it during short shut downs, just over night like starting in the morning to head to work. Is this a characteristic of advanced timing? I have been giving it a wee bit of throttle each time I start it since the 3K GSK install a LONG time ago. Now, for the last couple start ups I have to give it a little more throttle, and like I said in the morning, enough to get it to clear up and eventually idle. Any thoughts on what is causing the hard starting?



Thanks guys, Joe

 

[hsmith]

Probably a leaky supply or return fuel hose. Also check the pre-heater.

 

[JGheen]

I am not leaking any fuel anywhere, I searched high and low and I never messed with of the supply and return hoses. Only return line was the fuel drain manifold going to the fuel filter and it is leak free. Can they be leak free and suck air somehow?

 

[bmoeller]

Can they be leak free and suck air somehow?

Yes, it can. Check my RR pics in the "misc stuff" album. Have a couple of pics of my return hose. It was just starting to get wet. Not a short crack either. 3-4" long.

 

[JGheen]

Yes, it can. Check my RR pics in the "misc stuff" album. Have a couple of pics of my return hose. It was just starting to get wet. Not a short crack either. 3-4" long.

Well I will double check the hoses, but could it do the leak free and suck air thing through a used sealing washer on the drain manifold banjo on the fuel filter housing or any banjo on the injector drains for that matter?

 

[K5IP]

Mine starated slower after installing the 3 GSK kit. Turns out I set the springs up a bit too tight. After moving them back one click all is well.

Rog

 

[Andy Redmond]

Here's the short rubber return line on a 98 12v.



See this thread, I think its number 8 in the diagram



http://www.tdr1.com/forums/showthread.php?t=114425



Try ticking the idle up to just less than a thousand on the tach mark and I bet this will equal about 875 rpms on a scanner. Good for "foot starting" in normal temps, provided everything else the folks mentioned are okay.



Did your injectors come with new copper "horse-shoes" (return/drain gaskets at each injector)? These will often leak (weep) fuel if they have a leak or air leak then making for an easily identified leak and subsequent repair.



Good luck

Andy

 

[JGheen]

Did your injectors come with new copper "horse-shoes" (return/drain gaskets at each injector)? These will often leak (weep) fuel if they have a leak or air leak then making for an easily identified leak and subsequent repair.



Good luck

Andy

No my injectors did not come with any new drain manifold "horse-shoe" sealing washers. I have been keeping an eye on those to see if they were going to leak and so far so good.

Andy, I know you'll call me a liar till your blue in the face but I have looked high and low for this rubber return line that everyone claims my engine has, but it does not. I have looked wth the fuel filter off, flash light shining back in there and nothing but hard line all the way to the quick disconnect line around and under the filter housing.

For some reason the engine started with simple ease this morning and no stumble and stall, so maybe my issue is gone. I will continue to check the fuel lines and sealing washers but again, so far so good.



BTW, Andy, do you have Cummins part numbers for those horse-shoe drain manifold washers? If so would you have one for the sealing washers for te banjo on the filter housing? I tried getting them from my local Cummins place but they are idiots unless you have a part number.



Thanks, Joe

 

[biggy238]

Granted they didn't revise something:



Unless you have a pin head, you aren't going to make eye sight of that rubber section. It runs directly behind the fuel filter and tight up to the intake manifold.



Take the fuel filter loose and feel around under the manifold.



The return line is steel up until the section behind the filter, turns to rubber, and then back to steel at the back of the intake manifold.



An air leak can be anywhere. Just look at the B. S. i've gone through.



I think your springs are a click too tight.

 

[KYOUNG]

hard start

My 98 has Quick release plastic fuel lines on it

 

[Willys]

Usually you can feel around behind the fuel filter to find the supply/return lines. The return line starts at the overflow valve(between inj. pump and intake, near the front of the engine, but behind the timing cover area. Follow this hard line(probably only possible with your fingers) under the intake manifold, back around fuel filter like the last fellow said. Replacement hoses are available from larryb (IIRC, fostertruck.com). I don't know anything about the upgraded parts, sorry...

 

[Andy Redmond]

Joe:



Try 3903380 on the "horse shoes" they are likely about $3 a pop so 18 to go down the row. You can also source an injection reseal kit from any good injection shop that will include these and different copper sealing washers to shim the injector to the cylinder head (different b -series applications). A popular kit is made by dipaco DPE or DPZ5100 or 9100? Its about $25 and comes with plenty of extra parts not used on a Dodge B series application as well as the ones necessary for injector swap etc.



I don't have the number handy for the other seals you desire. Take your esn. and the diagram posted maybe the old point to trick will work. The esn number I used was for a 5spd 2500 truck manuf in 10/97. .



On the return line, I've yet to see a 98 12 valve that did not have the short rubber hose (7" vs the 14-15" used on the 94-97's). Keep looking.



I even changed one on a 12v (98) that should have been a 24 valve (maybe a little new years eve celebration) at the assy line to off load all the 12v's.



It should have the parts per the diagram.



If yours has the return line for the 24 valve I don't know how it would attach the metal return for the mechanically injected p pump (12 v). If you can get me a digital pic, I'd be interested to see the deviation from the norm.



Feel under the intake manifold approx at the front of the afc housing between the pump and the head/block. Find the end of the metal return line that originates at your overflow valve. You should feel some rubber line. This is a better diagram than the cropped version, you will recognize how it travels from the overflow valve to the oem return line near the starter motor on your truck.



Good luck

Andy

 

[Willys]

On the return line, I've yet to see a 98 12 valve that did not have the short rubber hose (7" vs the 14-15" used on the 94-97's). Keep looking.

Whoa, thats a new one on me. My parents have 2 98 12V's, I'll have to check them out. I don't think they've ever changed their lines, I've been through a few sets on my 96 since I bought it in '99.

 

[JGheen]

Ok, so I have narrowed my hard starting issue down to a possible shut-off solenoid problem. It seems to have trouble pulling the lever up when starting so I am gonna take it apart this weekend and clean it and lube the plunger up some to see if that helps.

Looked all over and found no leaks or wet spots anywhere on the fuel lines so most likely good there.

One small leak I found though was around the #1 injector and I am thinking it is coming from the "horse-shoe" banjo sealing washer on the drain manifold as I had to reuse all of the original stockers. HOWEVER, if the leak is not coming from there is there a slim chance the injector copper washer could be leaking up through the injector bore any? I am asking cuz I found fuel around the hold-down nut where the square cut o-ring is supposed to be but I am assuming it is the drain manifold? Any ideas, if that is the most likey culprit to the #1 injector leak I found?



Thanks, Joe

 

[Andy Redmond]

Joe:



I think you need a new shut down solenoid relay (above fuel filter mounted to firewall). They are available from Dodge $70ish or the aftermarket $20-30 (relay only not the fancy plastic and bracket). Send me a PM if you are interested in the 70 amp relay (aftermarket) and can't source one locally. You can temporarily remove the connector from the relay and source any 30amp relay and see if the solenoid arm retracts each time the starter is bumped and the key left on afterward. If this solves the problem source the HD relay and you are good to go.



I had to replace my relay for the first time this week, intermittantly it would crankover and not fire. When it would crank it was sluggish to start requiring more turns of the starter motor than normal. I looked under the hood after a no crank (key left on) and notice the solenoid arm was down. I grabbed a new relay from the tool box and its banged off quick everytime since.



Could also be the solenoid (bad pull coil--solenoid has a pull coil and a hold coil), blue fuseable link off the ds battery, dirty/poor connections, worn starter contacts etc.



FYI, I change relays about 9 out of 10 times to one solenoid replacement. The contact gets worn on the relay causing the complaint which you stated.



On your injector, loosen the banjo bolt (return drain line) and snug it up until it contacts, then another 1/8 turn and maybe a second 1/8 turn. If it still weeps after this, change the horseshoe. My money's on this one. Sometimes the injector turns in the bore a small bit and the previously compressed copper trys to reconform to the injector body and isn't up to the task.



Also loosen then re-snug the injector line to injector nut. Both steps are easier on a cool engine, as a hot exhaust manifold is not discriminatory who it burns!



If you tightened the injector, it would not leak up through the head. I would think it would have a bad miss and some compression loss, which you would hear if this were the case.



Good luck

Andy

 

[hsmith]

You may also want to check the leak at the injector. If the bottom sealing ring is leaking, it will show as dirty, almost engine oil looking. Will not cause hard starting issue though.

 

[hsmith]

Also, injector install kit from piers, very resonable, contains all seals needed.

 

[ELake]

My truck has the same symptoms as described, but it has stock injectors.

If you touch the throttle while cranking it over, it will start instantly.

Does that rule out the relay theory?

I stretched the OFV spring and replaced the fuel filter. The return lines look good.

 

[Willys]

ELake, I think you may need new brushes in your starter, and/or adjust the shut off solenoid. I had a similar problem, I thought my batteries were dying because the truck was getting slow and slower to turn over. The brushes finally bottomed out and shorted, while I was on a road trip. While on the road trip, I was trying to figure out where my power was hiding, so I found that the solenoid was out of adjustment and fixed it. Both a new starter was installed and the solenoid was adjusted within a few days, so its hard to pinpoint which one created a worse problem(with the slow to start issue). Up until the brushes bit the dust, I could start the truck in a split second with a little bit of pedal, but it would take several seconds on its own. Now it starts fairly quickly. I also bumped the idle up a hair in that time. Hope this helps instead of confuses you. I have a post within the last few months concerning the starter somewhere on here.

 

[ELake]

Yeah I read it...

I have a hard time believing its the starter - it sounds and seems to spin just as fast as any other cummins starter. .

Oh, I ruled out the relay contact theory, I manually lifted the shutdown solenoid up and then started it - still takes 4-5 revolutions to start.

One thing is for sure, it is consistant. It's to the point now where I can let off the key at just the right time and it will start... I'm going to put a fuel pressure gauge on the output side of the fuel filter and see what happens. It appears as though that particular fitting has a pipe thread (1/8 NPT?) on top of it. I just checked it out with a flashlight, I cant verify but I'm sure some of the experts can.

I'm also curious about the pre-filter or fuel strainer. Where is that located?

I just read about someone with the same type symptoms with a plugged strainer.