Got my 1st diesel in late November. Its a 92 W250 Ex. cab. I have been trolling around on here reading up and can't say enough for the information and wisdom I have learned so far.



Well I turned up my full power screw one turn and that really woke her up! I finally got around to truning my idle down today and I ran into a problem that I have not seen or could find a solution too. After only 2 turns down the screw backed away from the throttle lever and the idle only went down a few hundred RPM.



The idle is right where I want it to be except for the fact that I was going to turn the FP screw up another turn and I don't want the idle to be higher. Has anyone run into this before?

 

I'm kinda new to this first gen forum and i'm hooked because of the simplicity(simple- like me). I don't have the answer for you , but wanted to welcome you to the boards. you won't be disappointed. someone will answer that for you. crossy

 

On the other side of the throttle is the throttle rod and you will notice a ball socket on each end of it. Loosen the jambnuts, and turn the rod (like a turnbuckle) to lengthen it. There should be a slight amount of slack in the throttle (VERY slight, but you dont want pressure on it). This should loosen it up to drop your idle some.

Nice looking rig. Welcome aboard.

Daniel

 

Well unfortunately we tried that. Took the rod off alltogether just to see if it was causing it, thats when I took the pic.

I work at a Dodge dealership and even our diesel tech is stumped, but he is a newer guy and only has alot of schooling on common rail trucks.

 

If you had just installed a 3200 RPM spring I'd tell you the throttle arm was indexed wrong. That's not a lot of idle screw showing, you may not be able to get it to drop any more without re-indexing the throttle arm. You should not have to do that on a stock pump - was the anti-tamper cap still on the power screw?

 

The cap was gone, the funny thing is that the band was still welded to it but I made one turn in with no problem and its still not touching the locknut. I have no idea what the P.O. did to the truck. And I get really crappy milage, 13.8 is the best tank I have gotten so far and thats running empty and taking the 55mph highway for my 60 mile round trip to work everyday instead of interstate at 80.

 

It's been turned up already, then. It may just be cranked all the way up. Do you have a pyrometer on there yet? If not, get one ASAP. The 21 cm turbine housing on the '92's will let you hit meltdown temps at low RPM.

 

Ordered gauges yesterday. Good to know, I'll go extra easy on her till I get em in. Right now it will spin the tires from a stop if you nail it.

 

Welcome, nice truck.

 

Thanks! It needs rockers and cab corners, we will tackle those this summer. In the next few weekends I will be replacing the front U-joints and installing some Warn hubs, mine are in pretty bad shape.

 

Look to see if the fuel supply line that goes around the front of the injector pump is bumping against the throttle assembly anywhere. I had that happen on my 91 after I redid the pump, and it wouldnt idle back down. I reindexed the throttle shaft, and must have bumped it just right, cause when I got it all back together, it would idle at like 550rpm. Got it all lined out, though.

13.8 mpg sucks, even for a stock auto. CHange all the fluids, and get the injectors tested.

DP

 

As soon as I get the gauges in I'm going for the 190 injectors. Hopefully that will help.?.?