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What does this bolt really do? Need help with DB2 adjustment "turn up screw"

WarWagon

WarWagon

Well it hits on 7 of 8...
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(the local diesel shop would not do this for me so I have little choice but to do it myself...)

I could not get anything in the side cover of the pump without pulling the entire intake manifold. I had that cover off trying.

So I took the top IP cover off.

Had one of those "Oh $hit!" moments getting the assemblies out of the way.

What does this screw adjust? It hit the nut on the way out of the housing. So the nut was turned on the bolt. Is it simply a lock down for sealing diesel? Or is it the RPM limit screw for the governor?

See pic with bolt on top of IP. Note the throttle assembly rides on this. Was a white plastic cap on it.
 

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Yeah, one look inside of my DB2 and I closed it up. You have to remove the linkage assembly on the side of the IP, then remove the little cover with the two tiny 1/4 screws holding it on. Spin the engine over until you see the allen screw, insert a quality allen wrench and turn it clockwise 1/4 turn. You HAVE to use a inspection mirror to see the screw.
Sorry I can't help you on your question.
 
the way i turned my pump up was take top cover off, pull out the guide bolt for the govner asembly, (keep track of were everything goes take a good pic of it all) then rotate the engine over by hand (do not use starter motor will rev till it blows up) till u see the allen screw threw the top of the pump then rotate 1/4 turn or what ever u want (i turned it all the way in just when im pulling got to watch egt) then but back together but make sure u can hear fuel shut off soloind clicking like it should or motor will run away good luck
 
There is an orange spring that goes on the end of this bolt. It is inside of the spring loaded shaft 'governor control' just below the pictured bolt.
 
WarWagon said:
What does this screw adjust? It hit the nut on the way out of the housing. So the nut was turned on the bolt. Is it simply a lock down for sealing diesel? Or is it the RPM limit screw for the governor?
Click to expand...
That little doo-dah is called a 'guide stud', and it provides a smooth machined surface for the governor assembly to slide back and forth on. There's a small diameter spring that sits inside the governor assembly. The end of the guide stud hits this spring when the engine is throttled back to low/curb idle. On some pumps, the stud and bolt head are one piece, on others, the guide is threaded with a separate locking nut. Both use an o-ring seal under the nut/bolt head to ensure no fuel dribbles.
See pic with bolt on top of IP. Note the throttle assembly rides on this. Was a white plastic cap on it.
Click to expand...
Yup. Tamper-proof. Some are lock-tighted and sealed. Not designed to be adjusted in the field. Your best bet is to remove the pump and have a pump shop reset the adjustments. When you get it back, you can remove the cover and set the allen screw as you wish.

You also now have the issue of being absolutely sure that all the linkages are back where they belong. For example, the arm on the shut-off solenoid has a specific contact point on the throttle block. Miss that and you not only have no shut-off ability, but it causes the throttle to jam wide open with no governor override. Instant, catastrophic run-away. The pieces/parts gotta go back together exactly like they came apart.

No offense here, but basically, you're trying to pull a guy's wisdom teeth by going in thru his a**hole.
 
if you do decied to put it back together your self have some one stand close by with a board to put over the intake if run-a-way dose happen when i had mine apart i was alone and thought there is no way if it starts to run am i going to be able to get a board on it time so i had the park break set blocks infornt of all wheels and it in 5th figured i just dump the clutch it things went haywire thank god they didnt:D
 
Dave Barbieri said:
No offense here, but basically, you're trying to pull a guy's wisdom teeth by going in thru his a**hole.
Click to expand...

None taken - that is more or less accurate... There has to be a better guide on how to do this. I see two ways and one shows everything removed from the top cover area. I found that the throttle shaft can remain while you mess with this screw. How to get the allen wrench in the side for example would be helpful as I couldn't get it to work with the side cover removed.

I already have a board to stop any run away conditions.

I figure that the engine will not idle down if this is too far in or it will stall or jam the metering valve if it is too far out. I am sure I have it within 1 turn of where it was.

I see why the engine would run away as the metering valve is pulled wide open by springs in the pump. So as I put the cover on I watched the valve close from the stop solenoid assy.
 
Adjusting the guide pin sets the high rpm governor , if you go to far it will coil bind at idle.
 
You can do it through the top, with only removing the top, on the later 6.2 and 6.5 DB2 pumps. You need a good high quality ball ended allen wrench.

Banks has a writeup on how to do this.
 
When i did mine, i went in through the little triangle window under the throttle levers. I cut down an allen wrench somewhat shorter to just the right length, made it a lot easier. I had my wife look through the mirror to find the allen hole while i turned the engine over with the breaker bar. I thought that way was the easiest, compared to messing with the cap & solinoids. Took me about 15 monutes total.
Don
 
Acesneights1 said:
Go to Banks Website and download the manual for the 6.2 sidewinder system. It shows how to turn up a DB2.
Click to expand...

Thx. Banks site is INOP at the moment... :eek:

EDIT: Working now

http://assets.bankspower.com/manuals/430/96292-SidewinderTurbo-v2-web.pdf

And it says do not remove this guide stud...

midniteplowboyy is correct with a ball ended allen.

daustin said:
When i did mine, i went in through the little triangle window under the throttle levers. I cut down an allen wrench somewhat shorter to just the right length, made it a lot easier. I had my wife look through the mirror to find the allen hole while i turned the engine over with the breaker bar. I thought that way was the easiest, compared to messing with the cap & solinoids. Took me about 15 monutes total.
Don
Click to expand...

Tried that with several allen lengths. Broke the fuel filter drain hose getting it out of the way as the valve seized to the t stat bolt. I used a mirror and spun the engine by the alt. Was easy to align the pump screw with one person. Was very hard to see the bolt with the mirror.

Anyway I started the engine and everything works including the high RPM governor. Now got to work on even more air. :thumbsup:
 
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