1988 mercruiser alpha one, 4.3 thunderbolt, trim goes down ok but will only come back up with trailering button, where is the best place to start with this problem?
Re: Trim goes down ok, but only goes back up with trailering button, what ales it?
Usually it is the trim limit switch, it limits how high you can trim the drive with the up button. The trailer button bypasses the limit switch so you can raise the drive all the way up. It could also be the up button itself. Most times it's the limit switch. It's mounted on the gimble ring on the port side. Should have a "TL" marking on it. Sometimes you can take them apart and clean the contacts up and they'll work. To test your up button you can make contact between the 2 wires in the limit switch and the up button should work. Could also be that it is out of adjustment. Did it ever work since you have had the boat? When working with the trim wiring green wires are the DOWN circuit and blue wires are the UP circuit.
Usually it is the trim limit switch, it limits how high you can trim the drive with the up button. The trailer button bypasses the limit switch so you can raise the drive all the way up. It could also be the up button itself. Most times it's the limit switch. It's mounted on the gimble ring on the port side. Should have a "TL" marking on it. Sometimes you can take them apart and clean the contacts up and they'll work. To test your up button you can make contact between the 2 wires in the limit switch and the up button should work. Could also be that it is out of adjustment. Did it ever work since you have had the boat? When working with the trim wiring green wires are the DOWN circuit and blue wires are the UP circuit.
Thanks for the info, that gives me a place to start. The trim was like that when I got the boat the day before yesterday (1987 Regal Sebring Cuddy 19ft)! It needs some work before I can put it back in the water. It was in the water when I became the new owner. The scum is another story all together, But I'll check what you said about the trim when I get home today, thanks again....
Re: Trim goes down ok, but only goes back up with trailering button, what ales it?
Pretty easy to isolate the problem. In the stern, locate two black wires that come from the transom (trim limit), one plugs into a connector with 2 blue/white wires, and one with a purple white wire. Unplug the two black wires and jumper between the two connectors. Try your switch, if it works, your problem is the limit switch (or its wires). Good luck.
Re: Trim goes down ok, but only goes back up with trailering button, what ales it?
Mine was doing this as well. Adjusting the switch - limits how high it goes - fixed it. Just loosened the screws and twisted and works. I found a spec on how high it goes by the length of the cylinders and adjusted it.
Re: Trim goes down ok, but only goes back up with trailering button, what ales it?
I had the same problem; my black wires going to the port limit switch on the outdrive had lost their sheething around the bellows and were grounding out against the outdrive and touching each other; i used good electrical tape on them and haven't had an issue since. Had to crank the steering all they way starboard and sqeeze my hand in there...
Re: Trim goes down ok, but only goes back up with trailering button, what ales it?
Ok I rechecked it and now it is seems to be working right, I may have had it at the limit already when I thought it should go up more with the bow up switch, either that or something is loose somewhere, if it messes up again I'll start over.
Ok I rechecked it and now it is seems to be working right, I may have had it at the limit already when I thought it should go up more with the bow up switch, either that or something is loose somewhere, if it messes up again I'll start over.
Does it go all the way up when you hold in the trailer button? Shouldn't go up very much with bow up. If it did it could cause abnormal wear of the U joints, etc...
Re: Trim goes down ok, but only goes back up with trailering button, what ales it?
It may need adjusting. Run it all the way down, then up till it stops (with the trim switch). Measure center to center on the bolts holding on the hydraulic trim cylinders. For Alpha 1 should be 21 3/4 " . The adjustment is on the port side switch. loosen screws in slot rotate CCW to lengthen the stroke. Good luck.
