Yamaha F50T - power tilt problem

[Gary N]

Man, I am having some problems with this boat!

Anyway, I noticed that recently the power tilt has been getting slower and slower when the engine is raised. The boat has a new battery fully charged, but the rate of rise is now so slow it is difficult to see it even moving.

There does not appear to be any leaking oil from the hydraulic raising/lowering arm. However, the body of the tilt motor is quite corroded. My thoughts are that it may have allowed water inside.

The Yamaha engine manual I have is very brief in its description of the tilt mechanism.

Anyone worked on one of these? If I unbolt the Allen bolts that hold the body of the motor to its bracket and hydraulic assembly, will the motor come away for inspection of will oil squirt out?

[Chinook]

I don't have a Yamaha, but I experienced a power tilt problem with my Nissan 50 hp TLDI last fall. I'd been hearing a squeak noise for some time when raising or lowering, but hadn't paid it much mind. While out on the Chesapeake last September it finally failed. I was under sail, with motor tilted up, and I heard a clunk. The motor had dropped about half way down. It turned out that the pivot in the tilt mechanism had become corroded (not readily visible), causing the tilt mechanism to bind. The noise I'd been hearing was the pivot pin scraping in its bushing as it pivoted up and down. The ultimate failure was a break in the pushrod coming out of the hydraulic cylinder. This rod is welded to the tilt mechanism, and when the weld broke, the motor dropped down, bending the push rod. It was a fairly expensive thing to repair. Based on this experience, I'd recommend that you try to check the pivot pin, to make sure that it is turning freely and not binding up. If you can't get this pin to easily move, you may need to replace the hydraulic tilt assembly.

[Gary N]

I'm fairly sure it isn't a tilt mechanism issue, but I may be wrong.

When the engine goes down at normal speed, the mechanism doesn't shudder or anything, it just moves and pivots smoothly.

[Gary N]

We pulled the tilt motor off and it will actually operate sometimes. It will run in up or down mode until something happens inside it. After that point it won't run unless you move the motor spindle a bit, then the same behavior.

The nest step is to strip the motor down and have a look.

[Chinook]

I'm wondering if it could be a faulty solenoid. I had one go bad once, and the tilt behaved erratically.

[opie]

Tell us you checked the fluid level in the filler hole....

Mine stopped working like you described when I was low in fluid.

[Gary N]

Tell us you checked the fluid level in the filler hole....

No, because the problem seemed to be the motor.

Turns out that the motor was full of rusty water, lots of iron filings stuck on the magnets and the brushes seized up. The bottom seal was no good so that was probably the source of the water entry. We will try to repair it and see what happens.

[Gary N]

Also, anyone know what exact fluid to use in the tilt system?

[opie]

any ol' ATF fluid you have hanging around your garage.... seriously....

[Gary N]

any ol' ATF fluid you have hanging around your garage.... seriously....

Really?

Should all the old fluid be drained off first? It looks clean.

[opie]

read this link, 'cause I should not give advice on Yamy's when all I know about is Honda. The Yamaha may take a different fluid. Check with a dealer.......

[DaveB]

Opie,
Hows that new Rectifier/regulator working out? I acually loved it when it failed and got 17.5 volts chargeing my 2-27 house and starter battery.(no over heating or bubles after 4 hrs cruise,many times)..wet cells group27 deep cycles house.
My down fall was hooking into a Yandina combiner100.
The Combiner wouldn't except 17.5 volts so I had to pay the $117 for the new Reg./rect.
Dave

read this link, 'cause I should not give advice on Yamy's when all I know about is Honda. The Yamaha may take a different fluid. Check with a dealer.......

[opie]

Dave,

thanks for asking.

Not to hijack this thread, let me say that I had an issue or two with the regulator.

See this topic discussion where I posted some recent activity I had.

The new reg puts out 14.6 volts like it should.

[DaveB]

I should have put a post of your Dec. but things grow, have major results from system and will add to your Dec. post or add new.
Sorry got off subject.
Dave

Dave,

thanks for asking.

Not to hijack this thread, let me say that I had an issue or two with the regulator.

See this topic discussion where I posted some recent activity I had.

The new reg puts out 14.6 volts like it should.

[Gary N]

The pump is knackered so a new pump is on its way (£165). However, I need to replace some fluid in the tilt mechanism after replacing the motor. The manual I have say to remove the filler nut to put the oil in. However, the picture in my manual only shows one large bolt whereas the tilt body has both a large bolt head and a large slotted screw head above it just like the picture below.



Which is the fluid filler hole? The slotted screw or the hex head bolt?