1983 Evinrude 140HP Tilt/Trim Problem

[cmperry56]

Hello,
I have a 1983 Evinrude 140HP that is having a problem with the tilt/trim. The motor would trim and tilt fine but would not stay up. I noticed it was leaking fluid around the trim rods and I have replaced all the O-rings associated with the trim rods. It still doesn't stay up. It will go all the way down. I have read several different posts and in several places some of you have indicated the check valve is probably bad. I have looked at an exploded view of the unit but none of the valves are called a "check" valve. In the pic below I have circled the valve that I believe is the check valve. Can anyone verify that is the right valve?

 

[Joe Reeves]

Re: 1983 Evinrude 140HP Tilt/Trim Problem

There are many areas which could cause the "Tilt Cylinder" to leak down to the trim rams which would normally be the stopping point, including the tilt cylinder itself.

The tilt cylinder could be checked by removing the curled line from the bottom and inserting a blocked off fitting... a plug with a pipe thread fitting. Yes, I know you would need to make one as I did.

However, the two areas that are most likely to be causing the leak down are the rubber tipped relief check valve (#37) and the O Rings associated with the valve assembly parts (#5 thru #10) both of which are located under the oil pump assembly which in turn is located under the electric motor.