OMC 800 Trim Motor Issues

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Century

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I have a 78 Century with a OMC 800 Stringer outdrive. The powerplant is not original but is a 350 Magnum 270 hp Mercruiser. The Motor Trim solenoids are both clicking both in the up and down switched position but with no motor movement. I tryed increasing the battery amperage with 2 batteries and cleaned the wiring contacts to no resolve. Any ideas on fuse, wiring, solenoid or motor suggestions would be awesome. Also I would like to get a hold a repair manual for the beast as well. Any ideas? :confused:
 
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SeaSkwurrel

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Re: OMC 800 Trim Motor Issues

A couple of things to check. Check the clutch housing oil and make sure it really is oil. They're notorious for filling with water. Also, try tapping the motor housing while hitting the switch to see if there might be a short. Check for power at the motor wiring harness when hitting the switch. If you have power there, it's probably a bad motor. If it sounds like the motor is spinning but nothing's happening, it could be the hammer blow coupler (connects the motor to the worm gear).
 
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SeaSkwurrel

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Re: OMC 800 Trim Motor Issues

Sorry, lots of distractions here-I was thinking tilt motor. Messing with the tilt motor probably will have little effect on your trim motor! You may still be able to use parts of my suggestions.
 
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whywhyzed

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Re: OMC 800 Trim Motor Issues

I assume you don't hear the hydraulic pump running?<br />I would try jumping 12V right to the hydraulic pump motor and see what kind of spark I get... the motor could be dead...<br />no spark - try tapping on it<br />huge spark - it's seized
 
C

Century

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Re: OMC 800 Trim Motor Issues

Originally posted by SeaSkwurrel:<br /> Sorry, lots of distractions here-I was thinking tilt motor. Messing with the tilt motor probably will have little effect on your trim motor! You may still be able to use parts of my suggestions.
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Thanks SeaSkwurrel: I will probably do the tilt next but it seems to be moving at the moment.
 
C

Century

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Re: OMC 800 Trim Motor Issues

Originally posted by hystat:<br /> I assume you don't hear the hydraulic pump running?<br />I would try jumping 12V right to the hydraulic pump motor and see what kind of spark I get... the motor could be dead...<br />no spark - try tapping on it<br />huge spark - it's seized
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Mechanically I can get around but as soon as someone says "Electricity" I get dumb as a stump. When you say 12 V to the motor are you saying to come off of either the down or up power out side of the solenoid? If so what do I ground to? If tapping it does not help and there is no spark can I assume that its done and needs replaced? If so because of the age can I get it rewound or replaced?
 
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SeaSkwurrel

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Re: OMC 800 Trim Motor Issues

You would run power from the battery + post to the + of the motor. This would eliminate the solenoid and any other wiring as the problem. Grounding shouldn't be necessary-it should already be grounded (although that could be an issue as well). Make sure you vent the engine compartment for awhile first. You should be able to get a replacement on eBay if you need one. Just pull the motor and search on the model#.
 
C

Century

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Re: OMC 800 Trim Motor Issues

SeaSkwurrel,<br />I made up a remote switch to by-pass the dashboard and switch at the motor while doing readings off of the + side of the solenoid. There is power on both up and down solenoids. While energizing the downside I gave the motor housing a few taps and away she went. Unfortunately I can't get it up (No Pun Intended). I have resolved myself to replacing the motor. If you would be so kind to stick with me a little longer I will ask for some additional advice on removal of the motor. Its stuck way underneath the front cross member. Any secrets on removal would be appreciated.
 
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SeaSkwurrel

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Re: OMC 800 Trim Motor Issues

CAS,<br /><br />I'll have to get back to you a little later, after I look up a few things. I'm not familair with the trim motor setup in the compartment.
 
C

Century

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Re: OMC 800 Trim Motor Issues

Originally posted by SeaSkwurrel:<br /> CAS,<br /><br />I'll have to get back to you a little later, after I look up a few things. I'm not familair with the trim motor setup in the compartment.
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Thanks for hanging in there. The body is a Century 200. I think I would need Universals all the way up my arm to get in there.<br />Thanks again.
 
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SeaSkwurrel

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Re: OMC 800 Trim Motor Issues

I can't find much info in my 800 manual on that. Is it the OMC Select Trim?
 
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whywhyzed

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Re: OMC 800 Trim Motor Issues

Originally posted by CAS:<br /> I will ask for some additional advice on removal of the motor. Its stuck way underneath the front cross member. Any secrets on removal would be appreciated.
Click to expand...
OK, that's WEIRD... only the 4 cylinder and inline 6 cylinder OMC's used that style of trim. The V6's and V8's shouldn't even have a front crossmember.<br /><br />On my V6, the front engine mounts (at the engine's sides) are hydraulic rams to tilt.
 
C

Century

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Re: OMC 800 Trim Motor Issues

Originally posted by SeaSkwurrel:<br /> I can't find much info in my 800 manual on that. Is it the OMC Select Trim?
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Yes, Select Trim with a mechanical system. It seems to be like a jack screw that comes up through the crossmember and is driven by a reversable motor.
 
keelhauled

keelhauled

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Re: OMC 800 Trim Motor Issues

I have this same setup... yes, it's a gear-driven jackscrew --no hydraulics. These trim motors are just as cranky as the tilt motors.<br /><br />I unbolted the engine from the crossmember and raised the engine a little with a chain hoist. Gave me just enough room to get my arms in there to get to the trim motor.<br /><br />It's a real good time to replace the belt while the motor mount is unbolted!<br /><br />Good luck!<br /><br />P.S. Mine's also a V8
 
C

Century

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Re: OMC 800 Trim Motor Issues

Thanks for the reply.<br />Did you unbolt the nut on top of the jackscrew? I can't get at the bolts to the motor bracket as the motor is in its down position. Also when I get at the motor how did you pull the motor. There are 2 machine screws that go through the motor. Are these the ones I need to get at. Also the trim sensor is presently unhooked. How does the motor know its in the full down position or up position. What limits it? Where do the 2 wires go to from the sensor? Sorry for the barage of questions.<br />CAS
 
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