Trim/tilt fluid gone awol

I noticed the other day that the trim/tilt fluid level was right down (its hard to tell, but it looked like the reservoir was in fact empty) and the engine trim/tilt is no longer working. The pump runs when I press the button, but no movement on the leg (the leg is in the fully down position and the boat is out of the water on the trailer).

So today I bought 2 litres of 10W-30 oil and topped it up to full and tried again. The pump ran as before, the oil level dropped in the reservoir but still no leg movement and I can't see an oil leak anywhere.

I went through topping the reservoir up several times until I used up all 2 litres of oil, but still no signs of movement or leaking oil.

My question is where should I be looking for leaks? I have looked all round the pump itself, the hoses from the pump and the rams/hoses on the leg. I can't see anywhere where oil is leaking. The only place I can't view properly is the back of the bilge, so I will take a digital camera with me next time to try and get a shot of the back.

Also how much fluid is needed to completely fill the system? I was expecting just to have to top the reservoir up, but maybe not.

The trim was working fine last week when I took the boat out. Any other thoughts or suggestions welcome.

The engine is a 2002 Mercruiser 4.3EFI with Alpha 1 Gen 2 leg.

Re: Trim/tilt fluid gone awol

Under the engine is about the only place for it to be if you can't see it anywhere else.

Re: Trim/tilt fluid gone awol

I think you will see the oil around the back of the bilge. It can leak in just a few places. Around the pump which running the pump should show it squirting, the line to the transom mount which if running your hand all along the line would tell you that, at the transom mount itself which the back of the bilge would be full of oil, the back side of the transom which oil on back of outdrive or puddle under it would tell you that, the lines between transom and the cylinders which running hand again or looking for pool of oil, or the cylinders themselves leaking. That is a lot of oil you lost somewhere. It has to be somewhere and probably some place you can not easily see (hence the back of the bulge seems logical). The only other place I can think that you cant see is a leak developed in the transom itself but it happening would be a strange even that could happen (water in line right at that spot and froze causing expansion). Just grab a good light and try to twist your body in strange positions or start rubbing your hand everywhere to find the oil, then look for where it is comming from.

Re: Trim/tilt fluid gone awol

Ayuh,... With 2 liters gone,...
It's Gotta be either in the bilge, or on the ground....

Re: Trim/tilt fluid gone awol

Thanks guys for the responses. I will go down to the boat tomorrow with my digital camera and get some pics of the back of the bilge as that does seem to be the only place the oil can have gone.

How much oil does the system take to re-fill (assuming non-leaking)?