Power screw stop collar

[jbolt]

I popped the tamper caps off today to adjust the power screw. The stop collar on the screw is up against the jam-nut. Can I peel this off or is this considered max? Thought I'd check before getting crazy with the hamer & chisle.

 

[Gary - K7GLD]

On my '91, I had to actually grind off the areas where the spot-welds are, then peel the rest off with a chisel - a file would probably work as well - then you can adjust to yer hearts content - and it WILL make a difference! On mine, I also installed a second locknut, so when/if I wanted to make additional adjustment, I simple removed the whole screw assembly as a unit, made the adjustment, then put the whole assembly back and locked it down...

 

[Midnite]

I believe that's not the full-power screw, but rather the high-idle stop. There is a jam-nut (actually two) on the high-idle stop, but there are none on the full-power screw.



Mike

 

[sgriffing]

Originally posted by Midnite

. There is a jam-nut (actually two) on the high-idle stop, but there are none on the full-power screw.



Mike

Then you better put one on there.

You might want to check and make sure your power screw is still there.

It should take a 10mm wrench with the funkiest bend I've ever seen to get to that locknot after the timing is advanced.

I barely got a straight one on there with stock timing.

 

[BushWakr - RIP]

To confirm which is which you can look in my picture galleries for pump photo's and stuff.

However, the high idle screw has two 10mm locknuts on it, and this screw is on upper side of the pump towards the drivers fender.

The full fuel screw is lower down, and on the rear side of the pump, just behind the connectors for the fuel solenoid.

That screw should have a lock collar and a single 13mm locknut on it. The only way to NOT have a locknut is if that screw was taken right out, the locknut removed, and then screwed back in right up to the lock collar.

Since the lock collar is held onto the screw by a couple tack welds (not that strong in some cases, mine included) I would not rely on it as a 'locking device' or a substitute for a locknut.

If the locknut has in fact been removed then you may want to use caution if you remove the lock collar.

Screwing that full fuel screw in too far can have odd consequences.

You may encounter "runaway" conditions or you may find the truck start acting very poorly, hard running, bad idle or other things.

Make sure to mark everything before you change settings.



Bob.