Power Trim Issues

[kaw550]

For the second year in a row the power trim stopped working as the season ended.

The first year I noticed the fluid was milky. I drained, filled and cycled the trim a bunch of times. It fixed the issue for most of the following season (last year).


When I ended the season I repeated the same events as before with limited success. It would work once or twice and then the pump would get louder as the outdrive moved slower or stopped moving. I probably drained and filled the pump 10 times.

Now that I am getting ready to put the boat in the water, I want to fix it once and for all.

Is the fluid still contaminated or is the pump/seals worn? Can I disconnect the return line at the pump and drain all the fluid?
What steps should I take to trouble shoot?

It's a 98 Bayliner, with the 4.3 mercruiser. I used 30wt engine oil/

 

[Don S]

Re: Power Trim Issues

The pump is not hooked up to water, so pump seals are not the problem, unless water is leaking down on your pump motor. In that case, find a dry spot for the trim pump, and protect if from water getting on it.
Parts that are underwater are the trim rams and trim hoses outside the boat. Without the special gauges, not much of a way of testing them. You could try resealing the piston rods, that's the only way for water to get in.

 

[kaw550]

Re: Power Trim Issues

Do you think it is worth the effort to drain/fill a few more times or is it time to bring it to a shop?

 

[Don S]

Re: Power Trim Issues

It's time to remove the reservoir and clean it out. Too many nooks and crannies in them to hold that milky stuffl. Then, with the lines removed, run the pump and bleed the milky oil out of the pump. Disconnect the lines from the cylinders and blow the lines out with compressed air, Remove the cylinders and pump the piston back and forth to remove as much milky stuff as possible. Put it back together. Repeat as necessary.

 

[kaw550]

Re: Power Trim Issues

I took the boat out of storage and ran the trim up and down 4-5 times without issue. Should I count it as a win and move on (I did change the fluid several times before storing)?

I noticed that on the pump the lines are labeled up and down. Is the down the return line? If I remove line will it allow me to pump the fluid out of the system?

I assume that by the end of the season I will have the problem again but I am not sure there is anything I can do short of rebuilding the rams.