super slow...

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super slow...

Postby 01hillbillycummins » Fri Jan 13, 2012 7:51 pm

hey yall, ive been searching, havent been able to find anything yet. heres the story- its a 1990 w250, auto. 5" lift 37" toyos

it all started when I decided to rotate my fuel pin. I broke the banjo bolt for the boost line into the AFC. i figured, no big deal. truck sat for 3 days without a bolt as i cleaned the engine, air filter, and added some oil.

I went down to the Dodge dealer, told me the part is discontinued. Went over to Cummins, they said its a bosch part. After searching and searching i finally find one that fits. However, i put it in and realize the holes in the bolt are smaller than my stock one. i try drilling them out, and i dont notice a difference. i try drilling it out farther, but the bolt breaks again. I had to pick up another bolt, and the holes are smaller than the one that was in there originally still.

My truck got extremely slow all of a sudden. It really lags uphill. Any ideas how this could happen? i put the fuel pin back where it was, but still slow. My star wheel seems to be jammed or something, it wont turn at all. I cranked the smoke screw up to flush (i dont want black smoke) hoping to get more fuel, and that didnt help. doesnt even smoke at all. When i pull the fuel pin out, i dont see the follower pin when i move the throttle. tried running some power diesel kleen stuff, nothing.

any ideas at all? :cry:
1990 w250 Denny T II pin, 3200 spring, BHAF, DE 4" TBE, 5" lift, 37" toyos, kelderman air ride, 75 gal aux fuel tank
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01hillbillycummins
fuel screw!!!!
 
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Re: super slow...

Postby Tacoclaw » Fri Jan 13, 2012 9:13 pm

That pin should move when you move your throttle linkage, if it doesn't the truck will be a dog. You can improve it, but without that pin working it'll never run as fast as it should. There's a way to get it freed up, but I can't remember if the pump top has to come off or not.

Easy mods are to take up the slack in the throttle cable by pulling on it where it passes through the top of the pedal and shimming it. Then, move your throttle linkage to the inside hole on the injection pump arm and take your high idle screw completely out of the pump.

The big boy power is found on the screw on the rear of the pump. The "fuel screw", which also has the potential to make your engine run away. Basically, take the tamper proof cap off of it, back it completely out of the pump and knock off the ring they brazed on it to keep it from being turned in. Clean up the threads, and turn it back into the pump to where it was at previously. Then, take the inlet tube off your turbo, or intake horn, and grab something flat and sturdy that can completely cover whichever hole you're using.

Start turning the fuel screw into the pump 1/2 turn at a time, then starting the truck and giving the throttle a rev. The truck will rev up, and if you're on the edge of running away, will hang in the RPMs instead of coming back to an idle like normal. Back it off to where it still de-revved like normal, and she's "tuned".
1990 W250 4x4
Rattles, growls, whistles, and whines.
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Re: super slow...

Postby 01hillbillycummins » Fri Jan 13, 2012 10:35 pm

thanks man, ive definitely been contemplating the power screw adjustment. im gonna talk to my buddy who is a diesel mechanic and see if he can help me out with fixing the follower pin :lol:
1990 w250 Denny T II pin, 3200 spring, BHAF, DE 4" TBE, 5" lift, 37" toyos, kelderman air ride, 75 gal aux fuel tank
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01hillbillycummins
fuel screw!!!!
 
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Joined: Thu Jan 12, 2012 6:53 pm
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Re: super slow...

Postby cmann250 » Sat Jan 14, 2012 5:56 am

That guide pin got stuck in my truck too. There's a plug that you remove with a metric allen key on the front of the pump. its about 3/4" to 1" in diameter. Its on the pump, but your space to work is small because the timing case is right on the other side. I stuck the short side of an allen key in there and gently tapped it forward, pushing on the arm that pushes the guide pin into the fuel pin's bore. I sprayed it down with PB Blaster and pushed the pin back in with a flat blade screw driver. I worked it back and forth a few times and that fixed it for me.

I have a feeling this isn't how it's "supposed to" be done, but hey it worked for me :lol: I hope it helps
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Re: super slow...

Postby 01hillbillycummins » Sat Jan 14, 2012 6:46 pm

ill have to look into that for sure. thanks man
1990 w250 Denny T II pin, 3200 spring, BHAF, DE 4" TBE, 5" lift, 37" toyos, kelderman air ride, 75 gal aux fuel tank
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01hillbillycummins
fuel screw!!!!
 
Posts: 31
Joined: Thu Jan 12, 2012 6:53 pm
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Re: super slow...

Postby 01hillbillycummins » Sun Jan 15, 2012 8:50 pm

anybody got any other suggestions? 8)
1990 w250 Denny T II pin, 3200 spring, BHAF, DE 4" TBE, 5" lift, 37" toyos, kelderman air ride, 75 gal aux fuel tank
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01hillbillycummins
fuel screw!!!!
 
Posts: 31
Joined: Thu Jan 12, 2012 6:53 pm
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Re: super slow...

Postby delinquent » Sun Jan 15, 2012 9:12 pm

Take the big plug out of the top of the pump, you can see it once you remove the tps if applicable. Screws in from the front of the truck toward the back. takes like a 8mm allen wrech. From there you can push the pin in toward the "fuel cone" add some lubricant and move it back and forth till you are happy with the movement.
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Re: super slow...

Postby delinquent » Sun Jan 15, 2012 9:14 pm

just realized cmann offered the same advice. Kudo's to you!
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