outdrive kicks up in reverse

[bigones]

Howdy guys I just bought a new boat well to me anyways and I am having so problems with it. When I shift into reverse the outdrive kicks up. I have heard that there is a lock or some valve on it but I have no clue where it is. I believe its an alpha outdrive. Also the hose going from the carb to the engine the rubber one is way to big I think its a 5/8 would that cause a vac leak and cause it to loose power? Thanks

 

[Haut Medoc]

Re: outdrive kicks up in reverse

Post the year of your boat & engine make & size, at least.....
There is no vacuum advance in a marine set up.....

 

[bigones]

Re: outdrive kicks up in reverse

Its a 1980 20ft thompson, with a 470 mercruiser on it

 

[180shabah]

Re: outdrive kicks up in reverse

More details and include pics if you can.

We need to verify that you have a marine carb, before the explosion.

 

[Adjuster]

Re: outdrive kicks up in reverse

Your trim rams have failed is the reason for the outdrive kicking up.

 

[bigones]

Re: outdrive kicks up in reverse

Here is some pics

 

[bigones]

Re: outdrive kicks up in reverse

Is the trim rods any easy fix? I bet they are expensive

 

[Don S]

Re: outdrive kicks up in reverse

It may not be the trim rams, could be the reverse lockout valve is bad.
Here is a link to the OEM service manual which explains how to test and repair the trim system.
http://www-alt.mercurymarine.com/mnetdata/SERVICE/CRUISER/Servmanl/04/cover.pdf It's about 302MB, so it will take a while.
If you have a day or so, here is also the link to your engine manual. About 1.3GB.
http://www-alt.mercurymarine.com/mnetdata/SERVICE/CRUISER/Servmanl/03/cover.pdf