Mercruiser 40HP power trim

[bmitchell82]

Boat is a 1997, I believe the motor is as well. Power trim works fine going down, going up it intermittently does not work (Just clicks). Ruled out the relay by swapping the wires and the problem persisted. When I am able to get the up to work it is normally by rapidly switching between up and down on the trim switch and then up will start working. It will stay working for anywhere from a minute to a month, and then the problem will return.

I have also ruled out the switch being the problem as it occurs on both the trim switch in the boat and the one on the motor.

There were plenty of corroded wires, but best I can tell, all of them related to the trim operation are in good condition.

I was heavily suspecting it to be the UP solenoid, but upon further inspection and research, I found that this motor only uses one solenoid for the up trim, down trim, and starter. Both the down trim and starter work without issue 100% of the time. Is it possible for the solenoid to cause a problem for just the up trim when it is an all in one solenoid?

This is the style solenoid that it has: http://bpi.ebasicpower.com/pc/ARCSW054/OB-MERSOLREL

If that is not a possibility, what else could cause intermittent issues with the up trim only?

 

[bmitchell82]

Anyone have any ideas? Is it possible the trim motor is starting to fail? (I assume it spins opposite direction for up than it does down?)


Other than that, I can't seem to think of anything that would cause this other than possibly a bad electrical connection somewhere that I cant seem to find?

 

[GA_Boater]

I found that this motor only uses one solenoid for the up trim, down trim, and starter.

You sure about that? What's the serial number?

 

[bmitchell82]

Ok so apparently its a 98 Mercury, not a 97. But yes, I am fairly certain. Here is the serial number: 06650371 (Hard to tell if second digit is a 6 or a G)

 

[GA_Boater]

Your solenoid and trim relays aren't tied to one another except for power. You have a starter solenoid like you posted in the link. Trim is controlled by two relays - item 21 or 29 in the pic below. There is no way for one solenoid to power the starter and up/down trim, it takes a combination of 3 relays/solenoids. Find the relays and swap the two relays and see if the problem moves to down I used SN 0G055314 THRU 0G760299.

 

[bmitchell82]

I had already swapped the relays and the problem persisted. Would still go down but not up. Anything else you recommend checking?

 

[GA_Boater]

How did you swap relays if you thought you only had one?

Nevermind - Clean all the connections since you said there is wire corrosion. The ring connectors to the +/- and all the bullet connectors. Also pull firmly on the wires to make sure they are held well in the connectors.

 

[bmitchell82]

I never thought there was only one relay. I said there was only one solenoid. in my original post I even stated: "Ruled out the relay by swapping the wires and the problem persisted. " I will go back through and check/clean the connections, etc. Thank you!

I suppose my mistake was that I thought there would be a relay AND a solenoid for each. I am far from an electrician, but I have done what I know how and understood from research, and I did swap the wires from the relays.

 

[bmitchell82]

I am pretty sure it is a wiring issue. Way too many corroded wires to attempt to repair individual wires, how would I go about looking up what wiring harness this motor uses to replace it?

Thanks!