Shifting Problem

[firefighter1962]

Boat has twin 4.3 mercruiser I/O , when shifting from neutral to reverse both motors conk out 90 % of the time. ANY IDEAS WHAT THE PROBLEM MAY BE ?????
Only happens when shifting into reverse

[Bob H.]

Dave, I've seen this somewhere before but my memory is foggy. I think there's a history of neutral safety switch problems and adjustments (Quicksilver shifters?). So how's the "new" boat otherwise?

[firefighter1962]

thanks bob , i will check that out
She ran pretty good yesterday , still have a few things to work on
trim tabs not working ( have to check fuse )
motors not starting right up ( checking fuel filters today also changing plugs )
have to replace float switchs for bildges

[bottom scratcher]

Your engines have a shift interrupter switch that momentarily stalls the engine to eliminate harsh shifting. They have to be adjusted according to the type switch your engine has. Merc has roller type and plunger type switches. Each one is adjusted differently. You'll need a manual to adjust them properly. If the switch is not adjusted properly it stalls the engine too long and what you have is the result. Good luck.

[rj]

Ditto What Bottom scratcher said ,

also Binding in the drive or shift cable will cause the shift interrupter switch to kill the engine when shifting in to or out of gear.In most cases you must pull the drive to find the cause. The shift arm on the drive must be free to move with just your finger tips. If the drive is ok, the problem is usually the cable. Even though it may feel ok with the drive off it may be binding under load. If the problem started after overheating the engine, most likely the cable has melted

[firefighter1962]

Thanks guys will have it looked at right away