Need TBH Braintrust help... Outboard Issue?

[brunner]

I have a 2000 Yamaha 250 OX66 Saltwater Series. I am getting water building up in the pan below the block inside the calling. I have done several things to try and figure out where this water is coming from:

1. Ran the boat with the calling off with a buddy to see if I could see any water spraying from the water jacket or pisser hoses. Could not see anything but yet water was still building up in the back of the pan.

2. Dropped the lower unit and hooked up a hose to the water pump fitting. Turned on water and let the water circulate through the motor to see if I could see a leak from looking straight at the back of the motor. Again no water leaking anywhere at the obvious places. No water building up in pan under the block either.

3. Backed the boat in the water, leaving it on the trailer, and running the engine in gear up to 1800 RPMs with the calling off to see if I noticed any spraying or a leak. Again nothing. No water building up anywhere either.

It seems I have to run the boat at a higher RPM 2000+ for it to begin to leak. Could the water jacket only leak at a higher RPM?

Ideas or help is greatly appreciated.

[froghunter]

this is gona get typed out clear as mud.............

is any of the houseing around the motor loose or cracked? i have seen the aluminum houseing that goes aroung the lower unit develope a crack (at a seam) and when the boat is under way the water is forced into the houseing.

im sure that came out real clear

[brunner]

I will look. Will it have to be a page crack?

This motor sits pretty high up and normally the lowest third of the shaft and the lower unit is the only thing in the water.

[brunner]

Looked all around it no visible cracks but again the motor sits very up from the water line

[SaltwaterSlick]

I will look. Will it have to be a page crack?

This motor sits pretty high up and normally the lowest third of the shaft and the lower unit is the only thing in the water.

I was going to suggest backwash when shutting down, but if it's sitting high like on a jack plate on a shallow draft boat, that shouldn't be an issue. The only place where water enters this area is the water jacket and the "tattle-tale", so it has to be coming from the water jacket or a loose fitting, hose or a hole in the tattle tale hose if it is not coming from free water being either blown in the front of the cowling or backwash coming the back upon shutdown... water jacket leaks can be a real pain! ... experience talkin here, but not on a power head that big... I had a small Merc that ate my lunch for the better part of a whole season before I finally figured it out.

Good luck!

[brunner]

Ttt

[brunner]

I was going to suggest backwash when shutting down, but if it's sitting high like on a jack plate on a shallow draft boat, that shouldn't be an issue. The only place where water enters this area is the water jacket and the "tattle-tale", so it has to be coming from the water jacket or a loose fitting, hose or a hole in the tattle tale hose if it is not coming from free water being either blown in the front of the cowling or backwash coming the back upon shutdown... water jacket leaks can be a real pain! ... experience talkin here, but not on a power head that big... I had a small Merc that ate my lunch for the better part of a whole season before I finally figured it out.

Good luck!

Could it only be leaking at the water jacket at a higher RPM under a load?

[brunner]

Ttt

[brunner]

Ttt

[SaltwaterSlick]

Could it only be leaking at the water jacket at a higher RPM under a load?

Yea, the higher speed, the more pressure it develops. One of the little hoses on the tattle tale could be doing the same thing. I think those hoses are zip tied instead of having screw clamps. Might check that.