Bukh DV20 Idle Adjustment

T

theoldplucker

Well-Known Member
Joined
2 Apr 2008
Messages
271
Location
Cornwall
Visit site
Had to remove quadrant to get to anode hole for cleaning. Idle speed seems to have reduced. Nothing in workshop manual on how to adjust. Showing on VDO rev counter idling at 200 rpm ! Suspect rev counter to be under reading.
Looks like 2 methods to adjust idle. Turning up lower speed adjustment bolt on quadrant or, turning slotted screw in centre which is difficult as the smallest movement increases revs dramatically. Anyone know correct procedure ?
Thanks.
 
I believe that the idle speed adjustment on that engine (from when I had a DV20 in a previous boat), is by screwing in and out the electric stop solenoid, and re-locking it after.

I think the stop solenoid has to be unscrewed to raise the speed, as to stop the engine, the solenoid pushes the centre pin forward.
 
I have always adjusted the idle on my Bukh DV20 by adjusting the stop on the lower speed adjustment on the quadrant. I am not sure if you have the owners manual or the full workshop manual. The adjustment is covered in the full workshop manual on pages G14 and G15, you can download the manual here if you do not have it:

http://earlhill.de/files/Bukh_DV10_DV20_Workshop_Manual.pdf

Not a model of clarity, but it would appear that the Stop Solenoid is set up from the factory, and should not be adjusted without due cause.

You should adjust the stop, and if neccessary the nut on the governor arm until the engine idles at about 900 r.p.m. when against the stop. You also need to make sure that the engine will rev up to 3150 r.p.m. when fully opened up.

Hope this helps
 
theoldplucker said:
Had to remove quadrant to get to anode hole for cleaning. Idle speed seems to have reduced. Nothing in workshop manual on how to adjust. Showing on VDO rev counter idling at 200 rpm ! Suspect rev counter to be under reading.
Looks like 2 methods to adjust idle. Turning up lower speed adjustment bolt on quadrant or, turning slotted screw in centre which is difficult as the smallest movement increases revs dramatically. Anyone know correct procedure ?
Thanks.
Click to expand...

Sounds like you may have messed it up by not putting the quadrant back in the right place. On other engines I have recovered the correct position when this happens by slacking of the quadrant and putting the shaft back in the right position and retightening. The other methods of adjusting usine the solenoid and slow running screw are based on the shaft and quadrant being correctly assembled :D
 
I. too, have a Bukh DV20 with this same problem after lifting the quadrant assembly to access the anode. What is not clear to me from the Bukh shop manual is how to position the part of the governor that stick up through the quadrant, and to which the lever attaches that connects to the cable to the cockpit control lever. This part has a slot in the top which allows it to be rotated, but the slightest rotation causes massive speed change and there does not seem to be any governing going on.

I assume I'm missing some critical bit here in my interpretation of the instructions. I'd appreciate a explanation of how this bit works and how to set it up. I'm in Nova Scotia, Canada, the boat is a Westerly Merlin. There are no Bukh service depots here. Perhaps any diesel mechanic would know this stuff?
 
Finbar said:
You should adjust the stop, and if neccessary the nut on the governor arm until the engine idles at about 900 r.p.m. when against the stop. You also need to make sure that the engine will rev up to 3150 r.p.m. when fully opened up.

Hope this helps
Click to expand...

hello Finbarr
not meaning to drift, but I'm interested in knowing where you got the 3150rpm figure. I only ask as I could never find a max. referrence in the manuals.
thanks
 
philip_stevens said:
I believe that the idle speed adjustment on that engine (from when I had a DV20 in a previous boat), is by screwing in and out the electric stop solenoid, and re-locking it after.

I think the stop solenoid has to be unscrewed to raise the speed, as to stop the engine, the solenoid pushes the centre pin forward.
Click to expand...

No,do not play with the stop solenoid.It controls the max engine speed and has to be set carefully.
 
You must log in or register to reply here.

Share this page

Top