Stalls in reverse

[Anacletus]

I recently purchased a 1986 Condurre 230. Came across my first issue; the previous owner replaced the throttle, when putting into reverse, it engages and will “idle” back, but when applying any throttle, the motor stalls. Thoughts?

[nolaboater99]

You don’t say whether it’s a Merc or Volvo but I am going to assume it’s a Merc. Early Mercruisers have a shift interrupt switch typically mountEd on a plate where the shift cable transitions from the long shift control cable to the shorter shift cable. On your boat the plate may be mounted on the side of the exhaust manifold or maybe on the transom. Follow the shift cable and you should find it. On that plate is a small black micro switch. Merc Alpha drives use this switch to cause the engine to “stumble” just enough to release the load on the forward/reverse gears so you can get it out of gear. It usually works very well but if the Switch gets out of alignment it can cause the engine to die at the worst moment. It usually needs readjustment after the installation of new shift cables.

The procedure to adjust is not hard but if not done correctly it can cause problems. It sounds to me that the adjustment was not done properly, or at all, when the last cable was changed. Go to YouTube and search for “Mercruiser Shift Interrupt Adjustment”. There will be a number of videos that will show you the process. Good luck.
Shawn

[akorcovelos]

^^^what he said.

[mdadgar]

Merc Alpha drives use this switch to cause the engine to “stumble” just enough to release the load on the forward/reverse gears so you can get it out of gear.

Holy crap, what a miserable hack that is. Someone should have been fired for that.

- Mark

[Anacletus]

Apologies for the late response, but nolaboayer99, that was indeed the issue. When the previous owner replaced the throttled and cables, they did not adjust. All back full again possible. Thank you.

[nolaboater99]

Apologies for the late response, but nolaboayer99, that was indeed the issue. When the previous owner replaced the throttled and cables, they did not adjust. All back full again possible. Thank you.

Happy it all worked for you.