I spent a good portion of yesterday, wiring up all my new gauges into the truck. Went with all ISSPRO gauges and a three pod dash mount system that I will eventually have my body mold into the dash.

Anyways after I was done, my buddy says lets do some adjustments now that we can monitor it. So we first started with the power adjustment.

There is some kind of locking collar or tabbed nut that is tac welded to keep it in place.

Has anybody ran into this? And how the hell do you get it off. I want to see what this ole girl will do.

 

First off, pull the whole fuel screw out so you can work on it. A little fuel will drip out but it's not a problem.

Little screwdrivers to pry the ends up, and then you can usually twist the tack weld off. Do whatever is necessary to clean the threads up, reinstall the fuel screw and crank 'er up.

 

Make a note of how many turns it takes to get it out and start with it there when you put it back in, then go 1/2 turn at a time until you like the power setting.

Read the sticky on runaway before you start. Too much fuel and the engine could go ballistic and grenade itself.

 

My buddy was the one under the hood working on the power screw, while i was in the dash rewiring all the gauges and such. I know that he pulled a protective cover off the power adjustment but didn't get anymore of look than at that piece.

I ran out of light before I could look under the hood and see what he was talking about.

Can I take the whole fuel screw out by using a deep well socket? that should bust the tack weld and allow it to come out right?

 

the tack weld keeps it from going in more, not out
take your screw driver and unscrew the fuel screw remove the coller and clean the threads then reinstall at stock setting and then go up from there

and read the sticky about run away

 

Read the stickies before you do anything.

There are other things that can be done besides turning up the full power screw. Fuel pin, star wheel, smoke screw, more air, free flow exhaust.

 

I just happen to have some pictures here.

Yes,

They put it there so you cannot change the settings.

This is what the collar looked like just before it just fell off the fuel screw on my pump.

Before I removed mine I used a digital vernier caliper and measured the distance from the end of the screw to the casting and recorded it, I took lots of pictures of it and then I counted the turns as I came out.



They really spent some time if you will notice the intricate design the way it interlocks.



Here is what the working end of the screw looks like inside the pump.



And another.



Before you go messing with the fuel screw get yourself a piece of 1X6 or 2X6 and cut it square and cement a piece of neoprene that you can get from Home Depot in the Plumbing Department to the face of it.

This will be your Emergency Shutoff you will block off your Turbo Inlet with in the event of a runaway; of course you will remove your intake ductwork first.

Also have an assistant to help you; it is a bit un-nerving to be lying across your engine trying to block off the turbo as it is nearing the point of self-destruction.

Only do this if it is your truck, if it is not your, then RUN.

Jim

 

Thanks for all the info I will get out there and get this thing off when the rains stops.

 

Just be careful! In some trucks, just a turn or two makes quite a difference. In other, 4 turns makes no difference. Be prepared for runaway! Make sure everything else is working right before you do too much.

 

I went in one turn then checked the idle.
Then went one turn and checked the idle.
Then went one turn and checked the idle.
Then re-indexed the throttle shaft.
Then went one turn and checked the idle.
Then went one-half turn and checked the idle.
Then went one-half turn and checked the idle.
Then went back 1/4 turn and checked the idle.

Yes I got 5 full turns before I got runaway. But I also installed a 3200 spring before I turned up the screw, that may have delayed runaway.

 

On the '89 it took 3 full turns untill runaway. Actually had to back it out a little with the 3200 spring, it was lazy to return to idle.

The lock collar was right against the jamb nut, too. Still had the cover on it.

 

You may need to reindex your throttle too to get the idle lowered to turn the screw in some more.

 

I second that

 

My buddy has done this to his truck, so I sure that he knows what to do. But I will take all this info on board as we do this. I have a 3200 gov spring but havent installed it yet, so mabye I will take the thing out and change the spring before I adjust the power screw. This will allow my to get at that locking collar as well.