OMC 800 tilt & trim not working!

[AltonR]

I have an 85 Cobalt with a Chevy 350 motor. Out drive go's up and down when direct connected to the battery, solenoid clicks but replaced new anyway. Tilt and trim still don't work from the switch. Probem seems between the solenoid and the trim & tilt motors. Is a 2 volt voltage drop between battery and tilt motor. Can any on help? Thanks! Rich

 

[Howard Sterndrive]

Re: OMC 800 tilt & trim not working!

Lets troubleshoot 1 system at a time.
I can't follow if you are working on the tilt.
Or the trim.

Out drive go's up and down when direct connected to the battery
..........................................
Probem seems between the solenoid and the trim & tilt motors.

Not to me.
Sounds to me like the problem is more on the control side of the relay.

However, a 2V drop is a bit high. I like to see 1 max.

There should be an almost 12V drop across the motor obviously...
and as a rule of thumb, no more than .5V across any single connection or wire in the circuit.
..and No more than 1V drop total drop between battery + and motor green or blue when tilting.

What I like to do for stringer tilt, is remove the terminals from the relay and file both sides of each ring terminal shiny.
Then, file both sides of the washer shiny.
Then (most important...) file the side of the nut that faces the washer shiny.
It makes a huge difference.

Also check for tight pivot bushings on the drive - grease 'em lately?
You can remove the quadrant gear and lift the drive to see if it goes easy

 

[AltonR]

Re: OMC 800 tilt & trim not working!

Thanks! Good idea on cleaning the terminals. I didn't realize unclean they would cause that kind of voltage drop. Are you aware of any other relay in the tilt circuit besides the solenoid? The drive pops right up with no binding when connected directly to the battery. R

 

[havasuboatman]

Re: OMC 800 tilt & trim not working!

I agree with Howard S/D... It sounds like your problem is on the control side of the solidnoid. I would be inclined to look for either a break in the supply wire to the switch, Or (if you have a single lever shift/throttle lever) look to the wires inside the handle. The wires in the handle are prone to cutting inside. Especially if your shift/throttle lever is getting a little sloppy from age

 

[Howard Sterndrive]

Re: OMC 800 tilt & trim not working!

but then I reread that he said the solenoid clicks.... I missed that at first.

Hope he knows the tilt is not the trim...

Rich, in case you are new to this boat... always have the tilt all the way down before running the engine, and avoid tilting it up when engine is running.

 

[AltonR]

Re: OMC 800 tilt & trim not working!

Thanks! I am aware that raising the tilt with the drive engaged plays hell with the ball gear. But thanks for the reminder. I thought I was getting a voltage drop because the solenoid was going bad, I replaced it even though it was clicking. So far no difference, however, I confess I didn't clean the washers and nuts. Had to use the old hardware because what was sent with the new solenoids had the wrong threads. I Will clean and sand today and see if it makes the difference. I'm surprised that both the tilt and trim are affected. I thought these were completely separate circuits and motors. Any ideas?

 

[Howard Sterndrive]

Re: OMC 800 tilt & trim not working!

While you are cleaning connections, remove the two 50A barrel fuses (should be beside and behind carburetor on the harness bracket) and check for corrosion in there.

 

[AltonR]

Re: OMC 800 tilt & trim not working!

Howard, I have 11 volts to the tilt wire terminals but Zero to the tilt motor. I will check for continuity today but it seems unlikely to me that both the up and down wires developed breaks. If the 2 barrel fuses are blown would it kill power to the tilt and trim? Rich

 

[AltonR]

Re: OMC 800 tilt & trim not working!

Tested continuity and battery power to the tilt post on the up and the down solenoid raises and lowers to out drive. Solenoids still click from the switch but does not raise or lower out drive. I don't know what could cause two new solenoids to not transfer power from the battery to the up and down terminals. Rich

 

[Howard Sterndrive]

Re: OMC 800 tilt & trim not working!

What happens if you jump across the 2 heavy terminals with a screwdriver or heavy jumper wire? Jumping Red to green should lower. Jumping red to blue should raise.

Run the bilge blower before making jumper connections though...arcing inevitible.

If no go, and no arcing when jumpering, then you don't have good current flow to the relay lugs. Pull those 50A fuses and I'll bet they're all corroded.

You should have 4 relays if equipped with SelecTrim.

Tilt UP
Tilt Down
Trim UP
Trim Down

 

[WizeOne]

Re: OMC 800 tilt & trim not working!

I periodically pull my two 50A fuselings apart and spray them with electrical contact cleaner. They do get cruddy and refuse to pass power thru one pin or another.

 

[AltonR]

Re: OMC 800 tilt & trim not working!

Can you give me an Idea what the fuse casings look like? What I thought were the fuses turned out to be connectors. And Yes, I have 4 solenoids plus a 5th that operates the starter. I'll jump across the major teminals and again look for the 50 amp fuses this AM. Am I correct to assume that the out drive would not have operated by direct application of 12 volts to the up and down terminals unless the ground was OK?

 

[AltonR]

Re: OMC 800 tilt & trim not working!

I FOUND THE PROBLEM! I had a 50A blown fuse. Now to find a replacement. We have a West Marine. So will try them first. Thanks all for you help!!! Rich

 

[Howard Sterndrive]

Re: OMC 800 tilt & trim not working!

Car stereo shop your best bet for those fuses.

I FOUND THE PROBLEM!

Not really,
A blown fuse is never the cause of a problem. It is the result of more than 50A being passed through it. Something else is wrong.
If the filament is gently melted, your motor is probably drawing more current than expected.
If the glass is black and the fuse blew violently, probably a short circuit to ground somewhere in the wiring.

 

[AltonR]

Re: OMC 800 tilt & trim not working!

Now that I found the fuse. I recall that when I used the distributor wrench adjusting the timing I grounded the hot terminal on the solenoid. I think that melted the fuse. I've ordered 3 spares and from now on I'm going to use electrical tape on the wrench. Now I think I only have to deal with it running rough under load. Rich