'85 Johnson 70VRO Power Tilt/Trim Problem

[shelscot]

First heard this horrible noise yesterday at the boat launch. As I was tilting motor up to engage the trail lock, it started making a loud crunching noise. I immediately let off switch, went to rear and did not see any visible obstruction. Hit the switch up again and it lifted smooth with no noise.

Now today, while doing routine maintenance it is making the same loud crunching noise in both directions. The motor holds in all positions, so I know its not a seal issue. I put it up in lock, filled with fluid, lowered & raised and topped with fluid. Repeated cycle several times. It is functioning, but still making a loud crunching noise. Almost sounds like a gear issue. Only thing of note is that I noticed fluid was pretty foamy when topping off. Now I'm scared to death to engage the PTT motor at all.

The model number is J70ELCOS. Any ideas?

 

[RRitt]

Re: '85 Johnson 70VRO Power Tilt/Trim Problem

2w trim motors make a grinding noise when they have rust on inside. When rust gets behind magnets it will push them out from frame and into armature.

So have somebody run system while you stand back there and see if it is the electric motor. If so, then it has one foot in the grave.

 

[shelscot]

Re: '85 Johnson 70VRO Power Tilt/Trim Problem

Good morning sir and thanks for the reply. I've seen the term 2W & 3W trim. I'm not sure what that means and how would I know what my config is? The crunching/grinding noise is definitely coming from the motor area. Sounds mechanical and not electrical in nature.

 

[shelscot]

Re: '85 Johnson 70VRO Power Tilt/Trim Problem

OK, while tinkering around with the PTT hydraulic system some more I realized this:

Once the motor is all the way down, it does not make the noise when moving up or down in the "trim range" or first 15 degrees. Smooth as can be.

Also when the motor is fully up and the trail lock is engaged, it does not make the noise when continuing to press the down tilt to retract the trim rods.

It continues to make the loud crunching noise when going up or down in the "tilt range" and only under the weight of the motor.

Any engineers/mechanics out there with any ideas?

 

[Fed]

Re: '85 Johnson 70VRO Power Tilt/Trim Problem

The noise in one I had was the tilt ram binding where it attaches to the swivel bracket. There's a pin that goes through a nylon bush at the top of the ram. I removed the pin, cleaned it all up & lubricated it and the noise stopped. It was a grumbling noise that sounded like something was about to break. You could try squirting some crc type stuff up there.

 

[shelscot]

Re: '85 Johnson 70VRO Power Tilt/Trim Problem

Thanks for the reply Fed. Where exactly is this pin & bushing you're referring to? What is the swivel bracket? I am fairly mechanically inclined, but I'm new to boating, so pardon my ignorance.

The good news is that during my continued troubleshooting, I've learned that it is not the PTT motor at all. I've unscrewed the manual release valve and its making the same binding noise when I lift or lower the motor manually. So maybe it is exactly the same problem you had.

 

[Fed]

Re: '85 Johnson 70VRO Power Tilt/Trim Problem

Tilt the motor up then follow the tilt ram (the tall one in the middle) to the top of the shiny shaft, that's where the pin is.

 

[Home Cookin']

Re: '85 Johnson 70VRO Power Tilt/Trim Problem

if not there it could be in the steernig tube or other places where the motor moves.