engine hunts rpm on 1070 can I fix it?

I have a 1070 that the engine hunts rpm at idle to about 1400 rpm. Engine has a fresh overhaul and seems to be healthy all the way around. I read about some adjustments for this, but I was hoping some of you experts might chime in and post up a pic or diagram. I have the factory case manual.
 
my brothers 970 does that ,,. I think it is a timing issue , but my brother wont adjust it ,he says it aint hurting it ,,,. ,and the 970 simply runs reall good that way , other than hunting , when it goes into even a slight labor it levels out ,, starts good when cold weather ,plenty of power,. and no cold slobber . don't smoke bad either .. on the smaller 430 with 188, it has slotted titen areas on the fuel pump flange ,,.a little twist makes a world of difference for cold starting ,,.. bak to the 970, he lets it warm up at 12-1500 rpm when it cold starts .. with the straight pipe it is a cackler.,.. if any of you guys that KNOW , think this condition is detrimental to the 970 or 4240s turbo ,,. we REALLY need to KNOW ,,.
 
#2 on the diagram is the adjustment! You will have to take the 11/16 hex cap off and there is a flat screw driver adjusting screw loosen the jam nut with engine at idle running! slowly turn clockwise until it stops hunting it should not take much! Do not go any more than that tighten jam nut and put cap back should be good to go!
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Thanks, I did that on that adjustment, it made the rpm hunting go away, but the idle was slightly faster, making more grinding in the shifter, so I went back to allow for easier shifting. Any other ideas? How to idle it down? Thanks again.
 
Ok you Maybe able to set the idle on the throttle linkage with the 2 jam nuts on the pin if That doesn't idle it down you will have to adjust #1 on the diagram take 10mm cap off losen jam nut with it running and I think back it out slowly to desired rpm I think it's 725 rpm for idle for the 1070
 
Best way to set the low idle and bumper spring is like this, back out the bumper spring or take it out completely. Now set the top idle screw for about 150 RPM BELOW what you want the idle speed to be, then bring it up with the bumper spring and lock the nut and replace the cap if used. Newer Bosch RSV governors don't have the screw caps like the old covers did.
 
So by this you mean the upper or top screw; set that for idle rpm lower than desired after removing lower screw, correct?
 
Yes, top screw is the low idle stop screw, limits the lever internally. Set it about 150 below with the larger bumper spring assembly backed out. Finish to the idle speed you want WITH the bumper spring screw and lock. If you still have any surging and cab/platform mounts are OK then pump may have other problems if it has high hours. Worn plunger control sleeves will keep the equal delivery from staying in spec, loose/worn cam bearings can cause governor trouble too.
 

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