Trim cylinder bleeding/fluid recommendation

Knot 4 Me

New member
How do you bleed a drive trim cylinder after removing and rebuilding one? Do you simply cycle the pump up and down several times to remove the air? Also, the pump still contains the original fluid which I assume to be Merc's Power Steering and Trim Pump fluid. I have never had to add any fluid but on past boats I have used 10W30 motor oil to top the pumps off. Should I just use motor oil to replace the fluid I lose or should I change over to ATF at this time? If I do switch to ATF, how would I flush out all the old fluid? Suck out the reservoir, add ATF, cycle several times, suck out fluid, repeat? TIA!
 
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How do you bleed a drive trim cylinder after removing and rebuilding one? Do you simply cylcle the pump up and down several times to remove the air? Also, the pump still contains the original fluid which I assume to be Merc's Power Steering and Trim Pump fluid. I have never had to add any fluid but on past boats I have used 10W30 motor oil to top the pumps off. Should I just use motor oil to replace the fluid I lose or should I change over to ATF at this time? If I do switch to ATF, how would I flush out all the old fluid? Suck out the reservoir, add ATF, cycle several times, suck out fluid, repeat? TIA!

Mount it ,fill the pump up half way,,,and trim up and down until the air is all out,,,keep filling the res. in between don't let air get back in ....DONE !!!:cheers2:
 
Mount it ,fill the pump up half way,,,and trim up and down until the air is all out,,,keep filling the res. in between don't let air get back in ....DONE !!!:cheers2:
:iagree: Also make sure you check and fill the oil level with the drive down or it may :puke::sifone:
 
How can you tell whats in it? Just by the color?

I just added some Merc drive oil last summer to top it off, but didnt realize it could have been regular oil. I am going to drain both & put fresh Merc stuff in before summer anyway so i guess it wont matter.
 
How can you tell whats in it? Just by the color?

I just added some Merc drive oil last summer to top it off, but didnt realize it could have been regular oil. I am going to drain both & put fresh Merc stuff in before summer anyway so i guess it wont matter.

It is definately not or at least should not be drive lube in them. Drive lube is way to thick and will make them run slow. The easiest way to tell is by color. neither oil nor the ATF will change color very much and you should be able to tell.
 
I use the Napa clear power steering fluid. When bleeding after rebuild, of course you want to fill reserivor, cap the down fittings on the trim line manifold block, tap the up button until clear fuild comes out of the lines, then connect up lines to cylinders, trim up keeping the tank full. Once up to the stop, remove plugs from down manifold ports and tap down button until clear fluid, connect lines and top off fliud level and run down. That should take care of it.
 
I just usually take the rear ram ends loose and tip them down toward the ground ( make sure you brace them so they don't hit anything) then run them in and out a bunch of times. You will hear when all of the air is out.
 
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