Power Trim?

[mjwendorf]

I have recently pruchesed a jon boat with a 1994 40hp force. At one time it had power trim and for some reason it is missing the motor. Im guessing it burned up and they just took it off. Is there any way that I can check the cylinder or do I just have to get a motor and see if it works? It has 2 hoses that run to where the motor goes and it would be a 2 wire motor.

 

[Stachi]

Re: Power Trim?

are you sure it is a power trim and not a shock absorber ? Does it have lines going to and from it ? if it does , compressed air will aplied to either of the lines will tell you if the cyclinder is operable....post some pics of it

 

[mjwendorf]

Re: Power Trim?

I am positive it is power trim. Here is a pic,

 

[RRitt]

Re: Power Trim?

At first your problem was simply needing a trim motor rebuild. That system uses tall skinny motor/reservoir (see picture). But that sure looks like rust on the pump bolts. So now you're better off swapping out for a whole new pump assembly. You should also take the time to make sure that there is no water in system. I'm guessing $210ish to swap out what is in picture for new pump assy. If you have old motor and it is rebuildable then you'll save yourself about $60.

 

[mjwendorf]

Re: Power Trim?

At first your problem was simply needing a trim motor rebuild. That system uses tall skinny motor/reservoir (see picture). But that sure looks like rust on the pump bolts. So now you're better off swapping out for a whole new pump assembly. You should also take the time to make sure that there is no water in system. I'm guessing $210ish to swap out what is in picture for new pump assy. If you have old motor and it is rebuildable then you'll save yourself about $60.

When I got the boat it was missing the trim motor. My main question was how to test the cylinder/hydraulic.

 

[RRitt]

Re: Power Trim?

Your ram should be fine. Disconnect tubes from pump base, manually lift engine and block into place, cap off tubes, remove engine blocks. If it stays up then ram is fine.

 

[mjwendorf]

Re: Power Trim?

Thanks for the help.

 

[Stachi]

Re: Power Trim?

Again , I am saying this as a trained hydraulics mechanic...we bench test hydraulic cylinders with compressed air....apply compressed air to the line that goes to the bottom of the cylinder and see if it goes up and stays up while under pressure, you should be fine....you do not need to block off either line to do this...very simple to do....

 

[mjwendorf]

Re: Power Trim?

What kind of psi should I use?

 

[Stachi]

Re: Power Trim?

most small compressors are set to around 90 psi , just do it slowly...don't just blast it in there....ya don't want to shock your transom when the engine raises....also , you must disconnect the line coming from the upper part of the cylinder at the pump end of the line...if there is any fluid in there, it will need to escape (normal function of the cylinder) you might want to put a hose over the end of the line from the upper part of the cylinder and direct it to a bucket , as the oil IS going to come out if there is still any in there...

 

[RRitt]

Re: Power Trim?

Compressed air is fine for bench testing but inadequate for on-boat. It usually takes 600-900psi to tilt a force engine all the way up because the piston eye is so close to pivot point. Way easier to just grab the prop, lift, stick in piece of wood, and cap off lines. But, then again, 40HP may not have a heavy gear case or long driveshaft .... so maybe ... on a smaller engine .... if you have the compressed air handy but not brake fittings then give it a shot. No way it would give meaningful results on a 90-150HP .. but a 40? let us know.

*********************************************************
actually, I've been giving this some thought. I think you should steer clear of compressed air. I don't think it is safe with the ram mounted on engine. The caps are cheap. It's just not worth the risk.