outboards that run backwards?

[rdrfan]

At work the other day a guy was talking about an old style outboard that would run backwards. To go in reverse he said you had to shut the motor off and flip a switch then restart it and the motor would be running backwards for going in reverse. Has any one heard of this? I'm very curious and interested if any one has any info I'd like to hear about it!<br />Thanks a lot.

 

[Trent]

Re: outboards that run backwards?

It was called "Direct Reversing" and it was used by Mercury in the "Mark" series. It was used in the late 50's and early 60's<br /><br /> Wireing For Direct Reversing Mercury

 

[Joe Reeves]

Re: outboards that run backwards?

The Mercury outboard had that feature but that's going back quite a few years.

 

[JB]

Re: outboards that run backwards?

Howdy RDRFAN.<br /><br />Sounds like a neat, cheap way to get reverse on a "shiftless" engine.<br /><br />Getting many 2 strokes to run "backward" is a matter of changing the magneto timing and spinning her the other way to start. It does require a particular type of magneto to get it to fire either way.<br /><br />I was able to do this with some chainsaw engines for twin installation on my racing karts by using a magneto from lawnmower engines.

 

[sloopy]

Re: outboards that run backwards?

wow! I know J.B is going to kill me for adding a question to a anothers post. But why did it need a different magneto? and can I build my own chainsaw powered go cart?

 

[Gold Bear]

Re: outboards that run backwards?

rdrfan <br /> <br />The Mercury's had a pistol grip looking shifter with a button on the top. When you wanted to go forward you had to move the shifter slightly forward then hit the starter button. When you shifted back to neutral, the engine stopped. If you wanted to go in reverse, you had to pull the shifter back slightly, then hit the starter button again.<br /><br />The engines were lovingly (or hatenling?) known as "dock busters".<br /><br />Regards to all,<br /><br />Gold Bear

 

[rdrfan]

Re: outboards that run backwards?

That's very interesting. Thanks for replying guys. I appreciate it.

 

[SeaHorse]

Re: outboards that run backwards?

I had one of those old Mercs, affectionately known as a "dockbuster". It had a single lever control with the starter button on the top. You pulled back the handle and the motor would stop then pull back farther and press the starter and the motor would start in reverse...sometimes. The "sometimes" is how it got the name "dockbuster". My battery was always half dead so getting in and out of the dock was great fun. Water skiing was even more fun and I had the cut up ropes and almost cut up skiers to prove it. <br /> I had a lot of fun one day when it wouldn't start in the middle of the lake so I went back to pull it over (70 hp, 6 cyl, not so easy to pull over). When it wouldn't start I pushed the throttle up to about two thirds then went back and pulled again. When it started it almost threw me over the transom so I grabbed the powerhead to keep from going over. I had to steer by turning the powerhead since I couldn't get back up to the steering wheel since the boat was at a steep angle with me in the back. Like I said, these motors were great fun.

 

[JB]

Re: outboards that run backwards?

Hi, Sloopy!<br /><br />Welcome back. We missed you for a while there.<br /><br />Whether a magneto can make fire in either direction or not depends on the style of the cam that operates the points.<br /><br />Some mags use a cam that leaves the points open most of the time and closes them briefly when the magnets in the flywheel are passing the coil core. Others leave them closed most of the time and open them briefly to time the spark.<br /><br />If I remember correctly (it has been over 40 years) the ones that leave the points open most of the time are reversible. The others are not. Just switching the cam doesn't work. You have to use the whole magneto. I used Power Products chainsaw engines with power products lawnmower mags.<br /><br />Chainsaw engines make very good racing kart engines. For simple recreational riding around the 4 strokes are much more civilized.

 

[Jack Shellac]

Re: outboards that run backwards?

Recently read an article in National Fisherman [commercial fisherman's journal] about motors like this, except that they were inboards. I'd never heard of it, but apparently they were pretty common at one time.

 

[Forktail]

Re: outboards that run backwards?

I posted this about a month ago during a similar topic.... <br /><br />"The old merc reversing system (ironically called dock bangers) had two starters, each engaging and turning the flywheel in opposite directions. In order to go in reverse the outboard had to first be shut off. Then a toggle switch was flipped. Then the motor was again started (using the other starter), now running in the opposite direction. They had no neutral and were started either directly in forward or reverse."

 

[Hooty]

Re: outboards that run backwards?

The second boat I ever had was a 16' Yellowjacket with a DR800 and Speedmaster l/u. It was a real water rocket.<br /><br />Power Products 82? I remember them well.<br /><br />Sloopy, back in the dark ages, gocart engines were chainsaw engines first.<br /><br />c/6<br /><br />Hooty

 

[sailor_turned_stinkpotter]

Re: outboards that run backwards?

My gokart had an old snowblower motor on it<br />

 

[roscoe]

Re: outboards that run backwards?

Isn't there a new to outboards company that makes snowmobiles with a similar reversing setup?<br /><br />Starts with a "B", I think.

 

[Forktail]

Re: outboards that run backwards?

Not the same roscoe...a little more high-tech. <br /><br />Ski-doo's (Bombardier's) RER reverse system electronically reverses the direction of the engine through the electronic control module (MPEM) by retarding the ignition to a point where it idles so slow that the direction of the crankshaft rotation is reversed as the ignition is fired. The engine does not shut off. No starters. No toggles. No weight. No mechanical devices. No danger. Furthermore a unique helix was designed so the variable belt drive clutches could work in the opposite direction....something an outboard doesn't have to worry about.

 

[roscoe]

Re: outboards that run backwards?

Absolutely correct Forktail. But with innovative designs like that, Bombardier could turn the ob market in a new direction (pun intended). I think that they could surprise us all with some new designs.

 

[Forktail]

Re: outboards that run backwards?

That reverse do-dad thingy alone would eliminate an extra gear, linkage, etc. I'm sure they've considered many things like that. Bombardier is very innovative....that's why I have several of their products including that snowmobile with RER.

 

[sloopy]

Re: outboards that run backwards?

why don't they use something like that for twin outboard boats? would'nt that take place of the gear for counter rotation?

 

[Forktail]

Re: outboards that run backwards?

Yea, but then they'd have to manufacture a separate outboard that ran the crank the other way. And they'd still have to put a different prop on it. At this point it's easier (and cheaper) to just gear and prop.

 

[Franki]

Re: outboards that run backwards?

Thats an excellent idea...<br /><br />having a system like that could make the gearcase alot smaller for less water displacement in high speed setups..<br /><br />Just not sure how good it is for emergency stops in a boat.. like when you realise at the last minute that your about 20 meters away from hitting something.. how long does a throttled forward to a throttled reverse take in one of these things. (the Skidoo version I mean, not the Merc..)<br /><br />rgds<br /><br />Franki