need help ASAP 78 115 rude trim not going down.

[anderso8623]

I left my trim in the up position and now it won't go down. It is off the brace and if I run it up for a bit, I can get a little sound when I switch to down but then it dies. I can hear a click after the down noise dies.

For example, I make the trim go up for about 10-20 seconds even though it is all the way up. Then I try the down and I hear it try to go down (the sound is faint) but then it dies out and it stops making sound. At no point is the motor moving down

 

[Fun Times]

Have you checked battery voltage? Knowing what the cold cranking amps are is helpful too.
http://www.harborfreight.com/digital-automotive-battery-analyzer-66892.html

Some trim systems offer a manual release screw to allow it to go down.

 

[Fed]

Check your fluid level, make sure you put the support lever thing in place before checking.

 

[anderso8623]

Battery is fine, brand new august last year and fresh charge overnight. Fluid level is fine as well. It sounds as if the motor is going or already gone. However, while going up, the motor sounds strong like it was brand new.

 

[Joe Reeves]

The following will prove the PTT electric motor to be good or bad.... a starting point.

That 1978 model incorporates a large solenoid for the up mode... and straight thru wiring for the down mode. THe PTT motor willl have three (3) wires. Trace the three wires from the electric PTT motor back to its nylon connector. Disconnect it at that point. Run jumper wires from a good fully charged battery directly to the PTT electric motor... the negative jumper wire from the battery to the PTT motor's black wire, and the battery positive jumper wire to either the green or the blue wire of the PTT motor. One PTT motor wire should make the engine tilt up, the other making it drop down.

 

[Fun Times]

Have you tried adding some downward pressure by hand/sitting on it while running the trim motor down? Sometimes they may need a little extra help going down after being run in the up position to long.

Unseen corrosion buildup at the ram end caps could hold them in the up position as well.

 

[anderso8623]

I know the up works well because when I put it on the kick stand, per the local Evinrude dealer, I run it all the way down through both the tilt and trim, until the motor actually synches down. I got it off the kick stand by running the up through both the tilt and trim.

This is why it is odd, if the motor works for the up position, should'nt it also work for the down?

I can try both pressure and tracing the wires back.

 

[emdsapmgr]

After you do the test that Joe Reeves suggests, check the trim switch in the control box handle. Make sure it's making good continuity in the "down" position. It's always possible the down contact is burned or cracked.

 

[Joe Reeves]

This is why it is odd, if the motor works for the up position, should'nt it also work for the down?.

Becaue that model does not have a two wire (Dual Polarity) electric motor or relays.... It has a three wire electric motor with a (1) solenoid and as such, it can work fine in one direction and not at all in the other direction. You're getting good advice BUT check the electric motor out first as I suggested.

 

[glust]

I had a similar issue and the problem was not in the unit, but the switch operating the down. I had to replace the switch. The unit was fine. Go to the control box where the wires run to your throttle and short across them to make the unit think you are pushing the down switch. Sometimes the easiest thing to fix is actually what is wrong...

 

[anderso8623]

Trim motor was bad. Swapped out the trim motor and still did not work! Found this gem of a suggestion from Joe back in 2012 and was a quick 20 minute fix in the dark!

Re: 86 Johnson 90 Trim Tilt stuck

Sounds like you've possibly developed a hydraulic lock. This is usually due to trailering the engine in a tilted position without having it locked down. If so, the cure is as follows.

(PTT Hydraulic Lockup)
(J. Reeves)

If the engine has been trailered without having both of the trim rams pulled in, or trailered without even having the engine being supported by the trailering support, it is possible for the PTT to encounter a hydraulic lock up. The slight up and down motion, when trailering allows over 1700 psi of oil pressure to build up on the wrong side of the oil pump. Since the oil pump cannot exceed that 1700 psi, the unit is effectively hydraulically locked into position (the elec motor runs and does nothing).

The proper method for trailering is to have the engine in a full tilt position and resting on the trailering support bracket, then have both trim rams pulled in to a point where the engine makes a jerking motion. At this point, immediately take your finger off of the PTT trim switch. Now, quickly and sharply, tap the PTT up button. This removes the vast majority of down hydraulic pressure but at the same time, the engine is solidly locked into position and cannot rock up and down.

(The Cure)
Have the engine in the up position and supported so that it cannot fall. Look straight at the PTT assy.... you will see what looks like a large slotted screw on the port (left) side of the PTT assy, but which is in fact a check valve. Remove that valve and what you find inside which is a shuttle valve, and a spring on each end of that shuttle valve.

After you've removed those items, look straight inside of that chamber. You'll be looking at the reverse side of another check valve. Look at the hole in the backside of the valve you removed. You will need a punch that will fit inside of that hole.

Now, place the punch inside of the hole in that check valve that is still in the unit, and tap it rather sharply with a hammer. It will take quite a rap but the idea is to unseat the valve to release the hydraulic pressure. Watch your eyes as when you do release the pressure, it will have a tendency to spray out somewhat.

After releasing the pressure, reassemble the shuttle valve, springs, and outer check valve. Fill the oil reservoir with PTT fluid, having the engine in the extreme full tilt position. That's it.

 

[anderso8623]

Thanks for everyone es help!

 

[anderso8623]

One last question, the old trim motor would not run in the down direction, is it bad? Can it be fixed or should I just toss it?