91 mercury 75HP starter engages when I tilt and trim

[slowmocomotion]

Hello,

I have discovered this forum while searching for an answer to a perplexing phenomenon I am experiencing with my newly acquired boat.

I am completely green to boating and just purchased a 1994 Lund Angler Deluxe with a 75 hp mercury outboard. I was thoroughly going through the boat and motor in my drive way and I came across this problem.

When I turn the key the starter pops up, engages the flywheel and then proceeds to spin and turn the motor over to start with no problem.

When I hit up or down on tilt/trim the motor moves up and down respectively. The problem is that when I hit up or down on the tilt/trim the starter also engages the flywheel simultaneously. Once engage the starter only spins the motor/flywheel by about 10 degrees. It does not spin the flywheel much, no matter how long i hold up or down, but I did not think the starter was supposed to touch the flywheel while tilt/trim is being operated. To make it clear. When hitting up or down on tilt the motor does not spin like it would when I am starting it only moves the flywheel by an inch if that.

Please help explain if this is normal.

 

[CharlieB]

Re: 91 mercury 75HP starter engages when I tilt and trim

First you need a Factory Service Manual for your motor. Check these links

http://forums.iboats.com/showthread.php?t=309079&p=2072211#post2072211

http://1manual.com/Mercury manuals/Service_Manual_Index.html

Once you locate the correct manual, right click and 'Save as' to your computer.

Then find the wiring diagrams for the trim/tilt, notice the color coding and and start comparing to your motor.

I suspect you are going to find one of the trim wires connected to the wrong post on the starter solenoid, when the trim is operated it is attempting to power the starter.

The starter solenoid has two larger terminals, one has a single cable connected to the starter motor, the other may have one or two smaller red wires plus the cable to the positive post of the battery. The solenoid will have a single yellow wire with a red line, that is the trigger from the ignition switch.

Check these and repost what you find.

 

[slowmocomotion]

Re: 91 mercury 75HP starter engages when I tilt and trim

hello,

Thanks for the links to the wiring diagrams. I found the problem today.

The black wire coming from the up relay on the tilt/trim was connected to the negative terminal of the starter solenoid.

I took that wire and ground it out on a proper ground and now the tilt/trim works perfectly.