Yamaha 70 hydrailic tilt diagnosis and repair

[WhalerSal]

I have a 1994 Yamaha 70 two stroke, and the electric tilt and trim tilts up fine (so I dont think this is an electric problem), but it will slowly decline, and also leak fluid. Does anyone know this engine?

Where can I add hydraulic fluid?

What kind of fluid?

Any quick fixes to stop the leak? I dont want to throw money into a 15 year old engine if I can help it, although this is a nice simple well designed, but thirsty, two stroke.

[Cracker Larry]

On the trim cylinder about 3/4 of the way up towards the starboard side there is a large hex head bolt. That's where you add fluid. I'd use Yamaha trim tilt fluid, but I know others who use Dexron II hydraulic fluid.

Open the bleed valve on the starboard side of the leg and manually raise the engine and engage the trailer lock. Close the bleed valve and add fluid until it runs out. Cycle it a few times and top it off again. You may be low on fluid or have air in the system, although it's self bleeding. If that doesn't fix it, it will need new seals and a check valve. You can buy a trim cylinder rebuild kit with everything you need. seals, valves, wipers, O-rings for under $100 or a shop can rebuild it for about $250.

There are also additives for hydraulic fluids that can, maybe, expand the seals and temporarily stop the leak, but ultimately you need new seals and check valve, or you can maybe just add fluid once a month or so and live with it, depending on your disposition with such things.

Edited August 28, 2009 by Cracker Larry

[Cracker Larry]

Deleted: duplicate post

Edited August 28, 2009 by Cracker Larry

[WhalerSal]

Larry Thanks.

One marina quoted me $2400 for a new tilt and trim installed, another "well over $1,000".

I will try adding fluid and a sealant.

[autobaun70]

double check the manual release screw & make sure that it isn't barely backed off. This would cause it to leak down slowly as well.

[WhalerSal]

Thanks autobahn