Tilt/trim problem

[Capt dave 258]

Just picked up a 1992, 40hp Johnson with power trim. I had to remove the motor from the boat to get it home since I couldn't find the screw to release the pressure and manually lift it. I can here the motor when I press the up or down button, but it doesn't move. It appears to have been out of fluid and I filled it with trans fluid a few times and ran the button both up and down and it still doesn't move. I watched YouTube videos to try and find the release screw but no luck. On the very bottom of the piston housing are two Allen screws. One is much larger than the other. When I unscrewed the larger, it was under pressure and spit out the Trans fluid. The smaller Allen screw, I was unable to remove. Does anyone know where the release screw is on this unit? There is not a hole in the side of the mounting bracket that I can see, which is often the typical spot. Thanks for the help. See attached photos.

 

[Capt dave 258]

Found my release screw. See the above link. It was buried in the middle hole on the lower, port side and previous owner had it open. Too dark to work on it further tonight. Had to remove the long bolt that is threaded on each end and connects the pump to the frame. I was then able to lift the motor.

 

[Chris1956]

Sometimes you need to "help" the motor to trim up, by grabbing it and lifting. This will bleed them as well. Just let her sit a minute all the way up to allow air to bubble out of the fluid.

Usually, you fill them when tilted all the way up.

 

[Capt dave 258]

I'm filling the pump via the top hole, replacing the screw and running the switch up and down with no motor movement. When I remove the screw, the unit is still full. Can't quite figure it out

 

[Chris1956]

Run the PTT motor in the up direction, grab the gearcase and lift it. Use the manual tilt lock to hold the gearcase in the tilted position. Let her sit 5 min and refill.

Now unlock the manual tilt lock, run the PTT motor in the down direction and lower the gearcase.

Repeat a few times. That should bleed the PTT system.

 

[Capt dave 258]

The pump is leaking from the seal around the ram piston. I'm going to order a rebuild kit and address the leak. Thanks for your input. Hopefully I'll have better luck once that's done.

 

[Capt dave 258]

Replaced the seals and it's no longer leaking. I believe the pump is full of fluid and bled. The motor only goes up with me pulling up on it while holding the up button. My thoughts are the motor is too weak?

 

[Crosbyman]

cycle and refill a few times to purge any air .......unlikely you had 2 problems...seals and motor at the same time.

 

[Capt dave 258]

Well, I had the motor on a bench and ran it up and down and filled it until it would run out when removing the screw. I put the unit back on the boat and it will not raise the motor on its own. I have to lift up on the motor as I'm pressing the up button to get it to raise and once up, if I leave go of the motor, it lowers itself back down. Is this an internal problem with the pump, that it will not maintain pressure? I don't see it leaking anywhere. Frustrating!

 

[Chris1956]

Is the release valve tight? If so, a leak past the piston seal would cause that, but i would need to be a pretty bad leak.

 

[Capt dave 258]

The release valve is tight. I came across this video that may give me some insight. At about 13:43, it shows the guy working on the release valve. There is a small piece that goes in the body just before the release screw goes back in. I don't know if I have that piece or if it's missing. First chance I get, I'm going to take it apart and look further. There are also springs and poppets behind some of the larger screws. I'm going to check for them also. I'll have to see if those parts are available if they are if fact missing.

 

[Capt dave 258]

Yep, I'm missing the part that will seat in the port for the relief valve. I was missing the spring also, but found it under the engine in the grass. I checked for that missing piece that seats in that hole but cannot find it. Going to check to see if it comes with a rebuild kit.

 

[Capt dave 258]

Found the missing needle on MarineEngine.com. Waiting to receive it. Hopefully that solves my problem. I'll post the results. Thanks everyone for your help.