View Full Version : blackhawk stalling

05-31-2006, 11:33 AM
Has anyone had a problem with their blackhawk drive stalling the motor while around the dock :confused:

I understand the nature of the drive and the tough shifting etc.

when putting the drive into gear ( approx. 75%) time the boat will stall out and i will have to restart it
the motor fires right back up and will to the same thing again

The odd time i can give it a bit more throttle and it will go past the stalling but this isn't the best senario all the time
I don;t think this is a result of my gross incompetance :smile:

any suggestions?
installing a stall interuptor?



05-31-2006, 12:50 PM
Shea my BH drive was real tough to shift, I pulled the back cover and did a good greasing especially the detent plunger which has a ball, a sliding sleave and a spring. The detent is what gets real stiff, Merc was real cheap with the grease, Don Tamm had the same issue gooped it good and is now like butter.
I did not have any stalling issues with the SB but was not using the BH wheels, what is your idle RPM not sure but I think you need 7-750?


roadtrip se
05-31-2006, 01:47 PM
when mated up to the BH drive, according to Mercury. This was set in the computer by Mercury at the factory for shifting purposes.

The lube job shouldn't hurt either...

05-31-2006, 02:03 PM
My blackhawk idled at about 700-750 in neutral and 550-600 in gear if I remember right.

I had the same problem come out of nowhere. Ran fine all day then all of the sudden it would die every time I shifted into gear.

I got home and noticed there was a small allen screw that adjusted the secondary blade on the throttle body. I started it up and played with that until it idled up enough to not stall. It was a VERY small adjustment, but that was all it took.

I was later told by a merc mechanic that it was a big no-no to use that adjustment screw to adjust the idle. I then ask him why it was there and he replied "That's a good question". :boggled: All I know is it worked for me. I never had another problem over the next 3 years!

I also bypassed my neutral safety switch so I could start it in gear.

05-31-2006, 02:19 PM
I also bypassed my neutral safety switch so I could start it in gear.

Umm.... that sounds dangerous. :fire:

roadtrip se
05-31-2006, 02:29 PM
and in the troubleshooting guide, it mentions verifying the condition and tightness of the shift cable too.

No mention of the higher rpm requirement in the manual, the installation guide, or the promotional material I have.

05-31-2006, 02:31 PM
Umm.... that sounds dangerous. :fire:

As long as you have some common sense it's not! :D

Greg Maier
05-31-2006, 08:14 PM

Idle speed is/should be maintained by the Idle Air Control (IAC) Valve. This valve takes inputs from the engine (RPM, possibly crank position, etc) and opens and closes the valve to keep engine RPM at the predetermined level. If this valve gets dirty it can have an impact on idle quality. I never cleaned the valve on my boat, but I clean the valve on my Jeep Grand Cherokee about once every six months. The valve gets surprisingly dirty.

06-01-2006, 07:45 AM
I am changing the oil in the drive taday ( drained it last night and will be putting new oil in tonight)

I will take the top on of the drive as per Mop's suggestion and grease whatever I see

I don't think this is an idling problem with the motor as it seems to be working great, but I was talking to a service tech that seemed to think it may be a computer programing issue

Of course the Merc computer guy is apparently on sick leave for a month so I can't have it looked at until then when the tech has someone to talk to about settings



06-01-2006, 10:08 AM
Glas,do you have a mpi engine? if so clean the throttle and iac motor or your iac may have a dead spot in it..if your going to bump up the idle take a dvom meter and check the voltage at the tps(throttle position sensor)first..when you bump up the idle you will have to move the tps back the voltage reading before you bumped the idle up..
good luck

06-05-2006, 09:30 AM
changed the gear oil in the drive and it seemed to work real good over the weekend

didn't clunk or anything going in or out of gear and seemed to be quite silky

It did stall once or twice but i think that may be a computer setting on the motor as it was idling a little high some times (1000-1100) and other times it was right around 6-700

anyways boat is working great other than that (smoked a Powerquest yesterday) :rlol:

thanks for the help