Mercruiser 4.3 Trim problem

[MikeKovalchuk]

My power trim won't lower. The trailer switch will raise it, but I have no luck lowering it. I have someone coming out to look at it in a few days. In the interim, is there a way to manually lower it?

Thanks
Mike

 

[Don S]

Re: Mercruiser 4.3 Trim problem

Back on the trim/tilt pump is 2 solenoids, one for up, one for down. Just jump across the 2 large terminals to run the pump. Is it an Alpha drive, Alpha I Gen II, or Bravo? and What year.

 

[MikeKovalchuk]

Re: Mercruiser 4.3 Trim problem

Back on the trim/tilt pump is 2 solenoids, one for up, one for down. Just jump across the 2 large terminals to run the pump. Is it an Alpha drive, Alpha I Gen II, or Bravo? and What year.

It is a 96 Alpha 1.

I jumped the Gree/White harness wire and the positive terminal. The motor ran, but the trim didn't go down. Am I headed in the right direction? Thanks for your help! Mike

 

[Don S]

Re: Mercruiser 4.3 Trim problem

Well, if it's a 95 or 96 engine and drive, then it's an Alpha I Gen II drive. The Alpha I ended in 1990.

Here is the manual for your drive,

http://www.boatfix.com/merc/Servmanl/14/14cover.pdf

Section 1C has the troubleshooting section for the trim.

In your original post you said "The trailer switch will raise it, but I have no luck lowering it." which really doesn't say much. Does the motor run and the drive doesn't go down, does it just click? What is happening?

It may be that when you trimmed it up last you left the drive pressureized in the up possition which will sometimes cause them to hang when up.
Might run the pump in the down position for a second or so to make sure there is no pressure on it then stand on the drive (carefully) and jump on it. Possibly freeing the check valves. Then see if it will work.
Best when you put the drive up to just bump the down button to take the excess pressure of the pump and cylinders.

 

[MikeKovalchuk]

Re: Mercruiser 4.3 Trim problem

I got it lowered now by jumping it. Had it on the wrong wire terminal. Thanks for your help. I let the pros find the problem.

Mike