Water in Mercruiser Auto trans

I have a 74 sea ray 240, it has a ford 351 with some kind of mercruiser automatic transmission. the other day I noticed that the fluid in it was grey soup like water had gotten into it. I noticed there is a water line going into a plate on the back of the drive and another line coming out going to the exhaust. Is there a little coil in there that water flows through that maybe leaking? Anybody know what to expect when I pull that little plate off? this is the only way I figure water could get into the ATF fluid?

Re: Water in Mercruiser Auto trans

Most trans have an oil cooler it probably went bad.
You need to get the ugly stuff out ASAP.J

Re: Water in Mercruiser Auto trans

I just replied to this about 15 minutes ago, and it's gone

Anyway, go up to the Adults only sticky, (first thread in this forum) and find the Merc manuals link. Download manual #2 and go to section 6E page 2.
You will see where the cooler is located in the transmission.

Re: Water in Mercruiser Auto trans

What you have is a Merc Trans ll. Yes that is the cooler connected to that plate. You need to remove it so all the fluid will drain out of there. Water will cause the friction material to come off the clutch plates. Try not to damage the gasket when you remove it as they are NLA. However they are simple enough to make yourself. Inspect the cooler for any possible leaks. Usually when they leak the fluid level will get high in the trans and start coming out the dipstick tube. If the water wasn't drained from those lines over winter it will freeze and split the cooler. Don't ask me how I know. Fluid should be changed in those transmissions every year. If you need more info on that trans download manual #2 73-79 from the Adults only section. It has a complete section on it.

Re: Water in Mercruiser Auto trans

Thanks for the help guys I hope this system is all its cracked up to be when I get it in the water so far its just been on the hose.