Converting a Console Control Motor to Tiller Control
There may become a time when you want to convert a remote controlled motor to a tiller unit. OK, some of you think this is crazy, but just in case you desire this, here is my story.
My Johnson motor is a 1980 70 HP 2 stroke. In my situation this motor is on a jet sled that would normally be used in a river. These rivers I use it on in the Pacific Northwest are not large, with an average river being from 75' to 150' across just above the mouth. Once you get above tidewater, things start getting shallower and with riffles, bends, debris, holes etc. The fishing normally encountered are Steelhead or Coho salmon during the fall, when the water flow/height may fluxuate depending on the rainfall.
Some of the methods of fishing are "side-drifting" or "back-trolling". In doing so you will either be drifting down river holding the boat parallel to shore, casting toward shore, possibly maintaining the boat's position using a kicker or electric trolling motor. Or in back-trolling you head the boat upriver and use just enough power to very slowly slip downstream. You can move side to side in the river by using your kicker motor, which allows you to cover all the water in a "hole" or the tail-out above a riffle.
If you are using a remote controlled motor where the steering wheel with shifting/throttle controls are forward, the skipper is just that, giving him very little time to also be a fisherman. With the remote, if the skipper is at the stern using the smaller motors to control the boat and possibly also trying to fish, he has to be VERY alert to controlling the boat but MORE alert to what is coming up downstream than himself being a fisherman. If a snag, riffle, bend etc. comes up faster than he anticipates, he can not lift the small motor to keep it from chewing the prop in the gravel, run forward, start the main motor, maintain the boat's position from becoming crosswise of the current, save his rod that is still fishing and get the boat out of possible trouble all at the same time (GUARANTEED).
However if the boat/motor was set up for a tiller controlled motor, then that will allow the skipper to also become a fisherman possibly 80% of the time because he is at a position where he could start, yet maintain position with the main motor, raise the kicker, and slide on effortlessly downstream, or move back upstream out of harms way if conditions dictate.
This conversion was done on a outboard jet unit, which involved a little more that if it was to be a prop unit.
There is a growing demand for these used conversion units. I found mine on eBay. Now be aware that many of these eBay sellers may not really know what will fit, they may not even know what year it came off of. The 3 cylinder OMC motors range from 55 to 75 HP all appear to have the same mounting base whether it was designed for a tiller ort not. I found that (for me at least) that a tiller handle off a newer 1996 60 HP, bolted right on. The mounting bracket on the motor was the same as my older 1980 70 HP.
|Here we see the shifting handle, choke push button & battery cables|
The newer motors that use the shifting lever on the tiller handle will work on the older motors, (at least mine did). The newer linkage would attach directly to the the same linkage inside the cowling. I had to make my own shifting cable mounting bracket unit because of the jet out-drive unit.
In the photo below you see the shifting cable linkage that I had to make to be able to use the jet unit. However you will notice that the pivot shaft on the shifting handle is directly in line with the rubber grommet that the remote shifting cable went thru. The used prop linkage that came with the unit that I purchased would have attached thru the grommet hole and onto the internal linkage.
|My fabricated shifting adapter for the jet unit|
The electronics was something else. I found that the wiring bundle has more wires running in it than may be used at the console. Mine did not have a temperature gauge, warning horn, trim/tilt gauge, however these wires were in the harness. The trim/tilt control buttons on the throttle were controlled by a separate set of wires. Apparently some trim motors are controlled by either 2 or 3 wires depending on the year/brand of motor. The 2 wire appears to be the newer more common style. What I found was that the 3 wire set up utilized the 3rd wire as a ground, while the 2 wire system switches inside the solenoid contacts box mounted on the rear of the head so that the wire that was not hot to the trim motor acted as ground.
I have also found that these solenoid contact boxes differ from year to year on these motors after looking at mine and 2 of my neighbor's same size motors but different years.
You can cut the wiring bundle from that goes out of the motor cowling to give you enough length to splice the new wires together inside the LH side of the cowling. However I wanted to not damage this remote wiring in case that when I may sell this boat that it would be possible to return it back to a remote steering/controls. So I managed to purchase a used wiring harness pigtail for $50 off a salvaged motor. This way I saved the original wiring and made my connections wired into this used shortened harness.
You will have to do some testing of the wiring to confirm which wire goes where. The color coding may not carry thru.
|Here is shown the battery cables & the trim/tilt wires from the motor to the clamp bracket housing the trim motor|
The trim/tilt up/down buttons were purchased separately for about $30 that are used on most newer OMC outboards from a Bombardier dealer. It has both up and down buttons which is attached by a threaded stud on the back that is threaded for a standard 1/2" X 13 nut which was designed to be mounted on the lower cowlings by simply drilling a 1/2" hole. It comes with enough wire to be cut to length inside the cowling. This switch assembly was attached to a aluminum angle that was in turn tapped and threaded onto the bottom of the tiller handle. The wires run along the underside of the handle along with the wiring bundle of the kill button. With this trim button mounted here, the operator can have immediate control of raising the motor if need be when standing at the rear running the motor.
Also shown here in the photo below is the man overboard kill button/lanyard. A note of caution, if you bid on a unit like this on eBay the kill button assembly may have been removed as it was on mine. Having to add this little jewel will add to the conversion cost by only $130.
|Trim/tilt up/down buttons & the man-overboard kill button|
The new starter button is located in this tiller base, is activated by a button in the lower rear of the shift handle. This starter button has the wiring contacts inside with the actual push button mounted in the handle. The shift linkage needs to be adjusted so that in neutral, the push button and the actual electrical button are aligned, making for a neutral safety switch if they are not. This button is shown as the black button protruding to the rear of the handle pivot. It has the symbol of a key location and an arrow.
The large black rubber button in the center that I have added a blue (CHOKE) tape is obviously the electric choke button.
Here you can also see a couple of wiring harnesses running thru the old shift cable grommet & a couple of arrows indicating forward and reverse for the shifting.
The twist grip throttle cable for this handle unit has it's end compatible with attaching to the throttle linkage inside the cowling.
The one thing is that now with no steering cable, this motor does not have any method of applying friction to the motor pivot shaft, so the motor is very easy to turn. This may or may not be an issue when running. As in operating this system the skipper will usually be standing at the rear instead of setting, making for any slight move the possibility of very fast steering movement. However there is a aftermarket friction shaft unit that goes thru the original steering cable tube that is then attached to under the handle area that puts adjustable friction inside the tube to correct this if needed.
|Here the motor is mounted on my old 16' Hewescraft river jet sled|
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Originated 01-07-2011, Last updated 12-15-2014
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