Power tilt & trim with 70hp Chrysler

Joined
Jul 6, 2005
Messages
12
Hello. I have been struggling with my trim for a year now. I have replaced the pump with a brand new volvo penta pump, replaced the lines with new 3/16" hard lines and hoses, and took apart the cylinder to check for wear. I am using SAE 30 motor oil non detergent and 8 gauge wires to run the pump. I have the lines hooked up to the 2 ports that run the trim cylinder per the Chrysler service manual. The setup is not the standard setup. I only have the tilt cylinder acting as a single unit. It is a presolite trim/ tilt cyl. The problem I am having is that the outboard will raise and lower just fine with little or no load on it but when I am at 1/4 throttle or better it will compress the cylinder. Also it will not raise the motor under the load either, you can hear the pump running but it doesn't do anything. I can stand on the back of the motor and it will not raise me either (175 lbs). If the motor is slightly raised I can stand on it without it compressing. Any suggestions? Is the cylinder too big or not big enough to hold the motor?

Any suggestions will help!

Thank you!
 

MickLovin

Master Chief Petty Officer
Joined
Feb 18, 2013
Messages
822
Can you post some pictures of your set up, I take it you have a trim ram and a tilt cylinder, it is the trim ram which adjusts the motor in the water. I had a similiar problem, but it was due to the trim ram not engaging the stainless metal plate on the motor, the trim ram was moving and missing the striking plate it is supposed to hit upon, it was actually going to high and not giving me any adjustment and sinking the same as you mention. The tilt ram would not be the one that would hold your weight, it would be the trim ram and only to it's trim length.

I fixed my problem by adjusting the shaft the trim ram was mounted on, it's two bolts either side were loose allowing the shaft to move, therefore moving the trim ram out of place. Hope this helps, if not post a picture so we can have a good look at your set up.
 

Frank Acampora

Supreme Mariner
Joined
Jan 19, 2007
Messages
12,004
If your system has only the tilt cylinder to raise the engine with a small lock that engages a trim bar, then it is acting normally. The tilt cylinder is meant to raise the engine for very shallow water or for trailering. It has relief valves in the piston and will not hold the engine up at more than about 1500 RPM. It has very low hydraulic and mechanical advantage and will not trim the engine while under power or with a significant load on the lower unit (you standing on it).

If you want trim while under power, you must get a 4 port pump and the pentagon shaped trim cylinder that fits between the transom clamps.
 
Joined
Jul 6, 2005
Messages
12
Thank you. I ended up finding a smaller cylinder for the trim and one for tilt like the stock setup is. I think this may work. I will keep you posted.
 
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