Trimming problem

[Big Unit]

Hi,

I got a trimming issue on my mercruiser 4.3LX alpha 1 gen 2. I can trim it down but not up. The only way to trim it up is to use the ''trailer'' button.

Any idea?

Thanks

 

[ChrisCraftJohnny]

Re: Trimming problem

Funny, I have the exact same problem. My manual says that if this situation exists, (Trim Down & Trailer but no Trim UP) that you have a bad trim limit switch or bad wiring going to the trim limit switch. It makes sense. If the trim up goes too far up during cruising, you could cause major driveshaft problems. The limit switch prevents this. With a fault in the trim limit switch, it enters a "safe mode". It will not leave you stranded, but it will not work like it shoud either.

Not sure if this is our problem. Sounds good from the manual though.

Can anyone confirm this?

 

[jtmarten]

Re: Trimming problem

Have you tried adjusting the limit switch?

 

[stonyloam]

Re: Trimming problem

You are correct. You can check by unplugging the two wires (inside the boat) from the limit switch and putting an ohm meter across them. With the outdrive trimmed down it should read 0 ohms. You can also place a jumper across the plug that the wires go into. Try the up trim. If it works it is switch or wire. If switch or wire you can remove the trim limit (port side) switch (mark it's position well) from the gimbal ring, turn it over and on the older style (your 88) you will see two screws. Place a jumper across the screws and see if the up trim works, if it does your problem is inside the switch. You may be able to disassemble the old style switch, and clean it up to get it working again. If a broken wire you may be able to splice and solder it back together, and use several coats of liquid tape over the repair. Download Merc Manual 4A. Good luck.

 

[Big Unit]

Re: Trimming problem

Hi,

I have noticed that one of the 5amp fuse was burned. Maybe this could be the problem. But why, in this case, I could trim down? I can't be possible to have 2 fuses: one for trimming down and the other one for trimming up?

 

[stonyloam]

Re: Trimming problem

According to the wiring diagram (that I have) there are not separate fuses for up and down. Just 20 amp fuses in line on the main power from the switch.

 

[Big Unit]

Re: Trimming problem

Hi stonyloam,

Do you have the diagram in PDF format? Because I have another problem regarding 2 wires that are disconnected and I'm not able to find where they're supposed to be connected.

Thanks

 

[stonyloam]

Re: Trimming problem

No but: go to the "Adults only section" #9, download Service Manual #14 (Alpha gen II right?) and look at section 5, trim pump. Has troubleshooting guide and wiring diagram at end of section. Good Luck!