1992 Merc 200 Trim

[dsinger]

This trim has me stumped. The other day the motor stopped triming up when you were going. The motor will only trim about half the way but it you slow down to around 2500-3000 rpms it will go ahead and trim up like normal. It will also trim like normal at ideal. Any ideas. No leaks around the seals and it sounds normal.

 

[Texasmark]

Re: 1992 Merc 200 Trim

SWAG but has merit.

If your engine is like son's 150 in the center rear of the engine (between the cylinder heads) is an alum plate with several things mounted to it.....two of them being trim relays (have large wires attached).

Check the part numbers stamped on them. They should be identical. I'm assuming they have a connector that is removable, or screw lugs.

Swap connections to them (or physically change places with them) so that UP uses what was the DOWN relay. If your trim works properly replace the UP relay.....the contacts got crudded up.

Mark

 

[dsinger]

Re: 1992 Merc 200 Trim

Will give it a shot

 

[dsinger]

Re: 1992 Merc 200 Trim

Will swapping the solenoids did not work.

 

[Texasmark]

Re: 1992 Merc 200 Trim

Well your problem is elsewhere. Ok move on to connections.....taken from my 90-125 hp repair manual:

Merc uses one terminal on the starting solenoid to get 12v for the trim power (super place for corrosion) then 12v goes several places, one is thru a 20 amp fuse and goes to the trim buttons. I really don't think the trim button path is your problem as you only have trouble at high trim loads. The energizing circuit has no idea as to why you energized it....totally separate circuit from the high current path that runs the motor.

Other outputs go directly to the trim relays as do the wires from the trim unit.

Since you need the most current to trim out when at WOT, you are looking for a problem which does not allow you to get max current. Corrosion under or between electrical terminals is a great place to start......since you know (or now suspect) your relays are ok.....course both could have crudded internal contacts so don't rule that out.

Other thing, clean your battery terminals too.

Lastly could be some binding or a motor partially shorted.....but go after corrosion before you worry about that.

Mark