1999 Merc XR6 150 - Trim/Tilt Couple Questions

Mebster

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Joined
Jun 11, 2003
Messages
9
History - Skeg hit hard bottom at slow trolling speed.<br /><br />Symptom - Tilt up works fine. Tilt down works fine until you hit the trim rams, then motor spins for about 5 seconds with no movement. It does not seem to transistion from tilt ram to trim rams. After 5 seconds or so motor struggles to lower. You hear a noticable strain (air??) at this time. At first the motor would not lower at all past trim without additional pressure (weight) applied, then tilt ram would spring back up. I mucked with the manual release and have made some improvements but it still does not seem to transistion from tilt to trim like it did.<br /><br />Questions:<br />1) What triggers the transistion between the tilt and trim rams?<br /><br />2) How do you properly bleed the hydraulics on a trim/tilt system<br /><br />3) Do you really have to remove the motor to get this unit out (ouch)?<br /><br />4) Any other ideas?<br /><br />Any feedback is greatly appreciated!
 

Mebster

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Joined
Jun 11, 2003
Messages
9
Re: 1999 Merc XR6 150 - Trim/Tilt Couple Questions

This message board flies. One day and I'm down on page 3.<br /><br />Any takers on this issue??
 

Mebster

Cadet
Joined
Jun 11, 2003
Messages
9
Re: 1999 Merc XR6 150 - Trim/Tilt Couple Questions

Well guys, I fixed it. Can't say that I was overwhelmed with the feedback from the group. I assume no one has history on this problem so I'll supply the feedback myself for your future reference.<br /><br />If you read my original post, the problem occured after I bumped bottom. On older engines the motor was not physically connected to the tilt/trim unit. The motor would simply lay on the rams. Reverse lock was a hook that swung down and hooked the engine in place when shifted into reverse. If you hit something while moving forward the motor simply popped up.<br /><br />This is not the case with later model units from Mercury and I assume OMC as well. The main cylinder is physically tied to the engine. Reverse lock is achieved by the fact that you can't move the tilt cylinder when under pressure.<br /><br />If you remove the main cylinder piston, you will see small holes on the top. These holes are plugged by ball bearing/stem/spring mechanisms. This is the "impact relief" system. After a certain amount of force is applied (by hitting something), the hydraulic pressure will bleed through the holes creating in effect a leaky piston allowing the engine to kick up. Once the force is relieved, the springs press the ball bearings back into the holes sealing the piston again.<br /><br />What happened to me was that one of the ball bearings did not seat properly after I hit bottom. The symptoms were that I had no reverse lock and that the tilt/trim system would not go down once the motor hit the 2 outer trim rams. (Leaky main cylinder)<br /><br />What I did find in this experience is that these are not very complex devices and anyone with average mechanical skills should be able to fix them. The hardest part is having to remove a transom motor mount to get the tilt/trim unit off the boat if need be.<br /><br />If the motor doesn't spin then look to the solonoids, the DC motor, or corroded wiring/switch.<br /><br />If the motor spins but you have issues raising or lowering the engine then start with fluid level check, then move to locating leaky seals(o-rings)/pilot valves. Same holds true if you boys can't keep your motor up :D . Fluid in leaking where it is supposed to be sealed. In this case always start by looking at the manual release screw. This has 3 o-rings on it and any of them leaking will cause issues with the tilt/trim, plus it's the easiest place to start.<br /><br />One other possibility, in the case of Mercury anyway, is that there is a brass coupler between the DC motor and the pump that could break. Anyway, none of this is rocket science as I found out. Buying the manual helps but every manual seems to leave out specific details for do-it-yourselfers. If you need to get into the cylinders, better get yourself a spanner wrench to get that top cap off. I had to order one off the internet. <br /><br />Personally I think my situation was kind of a fluke. That's why it took me 2 weeks to find it. That's my story, and I'm sticking to it.
 
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