Tilt and Trim fluid

sdoomaha

Petty Officer 3rd Class
Joined
Oct 6, 2008
Messages
94
'94 Caravelle 4.3 Alpha - When winterizing, I noticed I could not see the level of fluid in the tilt and trim pump tank. Opened it up, and it was full, but the fluid has a definite light colored milky appearance, very similar to the lower unit gear lube when it has taken on water. Cannot find any leaks on the cylinders where it might take on water, so think it probably was left out in the rain with the drain plug in by previous owner and the water level in the bilge reached the punp tank and got in through the cap.

The service manual mentions the fluid getting contaminted and taking on a thick honey like appearance, but no mention is made of a milky appearance. I know I need to change it, but wanted confirmation before completing the work. I assume the easiest way will be to use the bleeding method noted in the manual? Disconnect the Out/Up hose leading to the trim cylinder and pumping it out, refilling the tank and doing again until I get clear fluid. Then disconnecing the In/Down hose and pumping again until clean fluid is being pumped form that hose cleaning out the bad fluid form the cylinder. Logic tells me to do both cylinders at the same time to avoid returning bad fluid to the pump from one side while doing the other.

Is my thought process correct? Overlooking anything?

Many thanks to all who respond.

Steve O!
 

Don S

Honorary Moderator Emeritus
Joined
Aug 31, 2004
Messages
62,321
Re: Tilt and Trim fluid

The only way I have found to get the milky (yes, that is caused by water) out of the pump reservoir is to remove the reservoir and clean it out. Put new oil in it and run the pump (both ways) to clean it out.
Also remove the cylinders and pump them full stroke by hand and pump the oil out. Blow the lines out refill and run it for a while. You may still have a tiny bit of milky oil in the cylinders but probably not enough to show up after bleeding it and running in and out a few times. If you do, repeat the process.
 

sdoomaha

Petty Officer 3rd Class
Joined
Oct 6, 2008
Messages
94
Re: Tilt and Trim fluid

Many thanks Don. Will follow your advice.

Steve O!
 
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