Mercruiser Stern Drive Tilt Stuck in the Up Position

[skipmac]

OK. My dirty little secret. I have a power boat that's not a dinghy and need some help.

This is a 1994 Mercruiser with an Alpha One stern-drive. It has been sitting on the trailer for about 8 months with the drive tilted all the way up. Went out to crank and run it and the stern-drive will not tilt down.

1. The batteries are fine.

2. Switches are operating correctly.

3. Motor sounds strong and sounds like full rpm in up and down but the drive doesn't budge.

4. Fluid reservoir is full.

5. Jumped up and down on the drive and tried the power tilt again, still no movement.

6. If I hold the switch up the motor runs for a second and bogs down like normal when the drive reaches max up or max down position.

From the symptoms I am guessing it is something in the pump or valve section of the trim/tilt unit. Anyone familiar with these and any quick checks I can do without total disassembly?

[skipmac]

Fixed, if anyone is interested.

Got a 250 lb mercruiser mechanic to jump on the outdrive while I hit the down trim switch. Of course this would not have worked if he had not been a Mercruiser mechanic.

Without disassembly his best guess was a stuck valve in the hydraulic system. Suggested tilting it down slightly while the boat is laid up.

At least I now have a way to get on the water while the sailboat is still in overhaul mode.

[US1Fountain]

Leaving your drive stored in the up position isn't the best, especially in cold temps and with bellows of age. Your u-joint bellows takes set, being stretched out on the bottom side. Best if you can store with drive in full down position for periods of time.

Have also heard of stuck drives and a good jouncing will free it up. Most suggests it's the rams that are stuck. Also when your drive is stored up, leaves all of the trim rams rods exposed to elements.

[RatzelsRide]

I am having the same problem. However the oil was very milky in the tank. Would this cause the shafts to rust?

[skipmac]

Originally Posted by RatzelsRide

I am having the same problem. However the oil was very milky in the tank. Would this cause the shafts to rust?

Milky oil is the classic indication of water in the oil. Water certainly promotes rust so that could be a problem but I would still consider the rams are stuck if the drive has been stored tilted up for a long period.

I don't use my power boat very often and almost ever time I get it out the drives won't go up or down. It has become standard procedure for me to bounce on the drive while my wife plays with the trim/tilt buttons. So far it works every time. I would give that a try but still you need to drain all the oil and refill a couple of times to get the water out AND find the source of the water intrusion.

[RatzelsRide]

He is trying to remove the trim arms and is having trouble with the back part. He can't get them to come off the pin
Is there a trick to remove these ? I sure hope so cuz he's driving me nuts. Lol

[skipmac]

Originally Posted by RatzelsRide

He is trying to remove the trim arms and is having trouble with the back part. He can't get them to come off the pin
Is there a trick to remove these ? I sure hope so cuz he's driving me nuts. Lol

There's a pin on both ends of the arm. Do you mean the end over the propeller or the end at the transom of the boat? Either way why remove the arms? If the arms are just jammed so the tilt won't move up or down then you can probably fix it without taking it apart. In fact it might be easier with it not taken apart.

This was how the Mercruiser mechanic from the local shop fixed mine. Get the biggest person you know to stand on top of the outdrive and bounce up and down while you push the trim/tilt buttons. Don't just hold the button down, you might burn out the motor or the pump. Bump it for down AND up, holding it a few seconds in each direction at most. That's worked every time for me.