I pulled the cooler off and tested it. Does not seem to be leaking. I do not see power steering fluid any where, any ideas?

Boat is an older 85 Scarab with twin TRS set up

Thanks Steve

If there isn't any oil leaking anywhere than it has to be the oil cooler.
The oil is going somewhere.

Put 15psi of air into ps cooler in line and cap the out port. Then drop it in a tank of water and watch for bubbles.

another great tool to have as I mentioned about 100 times. A outdrive / gear case pressure tester tool. Test all kinds of coolers - water / oil and test water pressure sensors - exhaust manifolds and risers, headers and all kinds of reservoirs including outdrive reservoirs, heat exchangers, even test fuel rails, cool fuel modules and so on and so on.

Testing power steering cooler a couple of weeks ago on 350 HO MAG

You can test right on the engine and in the boat. Its a hand pump to 30 psi but one can really go higher if change out the gauge.

I would think you would have all kinds of pretty rainbows behind the boat if you were pumping that power steering fluid into the cooling water and out the back. Does it do it at idle also, or just at higher RPMs?

You could also bypass the power steering cooler and run it with none for a while to see if you're level drops.

I had an intake leak I couln`t find. Bought a smoke machine and I love this thing. Found the leak in 3 minutes. It is awesome. Where ever there is a leak you get tons of smoke.

I haven`t run a cooler in 3 years. I have temp indicators on the pump, temp is no problem.

if you are loosing it that quick and the bilge is not red has to be the cooler...not burning it