Fuel Screw

[cerberusiam]

sometimes the threads on the screw suffer when the collar is removed and you can get a false bottom. 

Are the stock fuel screws all the same legnth?

That makes sense about the threads. .

I'm betting the screws are the same length.

One would think the screws should be the same length but... ... ...





There is a noticeable difference between bottoming the screw and hitting messed up threads. The case threads are a lot softer and little pieces will come off them if you are not careful. :{

 

[JLEONARD]

There is a noticeable difference between bottoming the screw and hitting messed up threads

I'm betting that the position of the lock collar varies somewhat pump to pump. I don't know Bosch's process, but I would think that the pumps are calibrated 100% and thus differences in tolerances put that collar in different positions based on that calibration procedure. That also might account for why some engines seem to respond a lot to moving the screw and some not so much.

??

 

[SPoe]

I've tweaked the fuel screw on my 93 D250 and it's been bottomed out for about 6 months now and my plan was to back the screw out but it's stuck with no signs of turning in either direction. Does anyone have any suggestions to move that screw?

 

[R C Cola]

Just maybe ?

You most likely already checked this but just in case, Mine has a locknut that has to be loosened before that screw can be moved.

Could that be the problem ?

 

[SPoe]

yes i have loosened the 13mm nut but the screw still doesn't move. im affraid of breaking anything. ive even spayed some WD40 on it and let it sit a while and the screw still doesn't budge.