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Starting in Reverse?

Posted: Sat Jul 11, 2015 9:20 pm
by polc1410
So I'm sat at my Dad's house commenting that the new tpoy doesn't have reverse and that in the wrong wind/tide conditions that makes starting at a slipway and leaving without fouling the propellor. He's a mechanic knows some stuff about engines... ...he says if I coil the rope the other way on the starter will it start in reverse?

So - will it? And will it do any harm?

Re: Starting in Reverse?

Posted: Sat Jul 11, 2015 9:58 pm
by Charles uk
It wasn't designed to start backwards, but there is a remote possibility it might run badly, but be very difficult to start, ask him to check out the relationship between the flywheel magnets/ignition coil & the point that the points open when rotated backwards, that shouldn't prove too difficult for a mechanic.

Please let us know what he finds.

Re: Starting in Reverse?

Posted: Sun Jul 12, 2015 11:44 pm
by headdownarseup
I once had an old toyota that did that.
5 reverse gears and 1 forward gear....interesting
Nearly went into the front of the car behind me at the traffic lights. (1st gear is now a reverse gear as the engine is running backwards)
Mind you, it filled the cabin with lots of smoke from running backwards for 30 seconds.

Never did it again though-- strange never the less

jon

Re: Starting in Reverse?

Posted: Sun Jul 12, 2015 11:53 pm
by Charles uk
I think you ought to type "Honest" at the end of that post!

Re: Starting in Reverse?

Posted: Mon Jul 13, 2015 8:28 am
by Keith.P
Being lazy at the time, I was unloading the back of the lorry, first off was an Ausa forklift, right on the back of the lorry, easy just to roll off, but I decided to bump start in on the way down, it was a little slow rolling off so I dipped the clutch to let it roll all the way off, but as I did that it started backwards, which made a mess of the air filter.

Diesel three cylinder kubota if I remember correctly.
"Honest"

Running a seagull backwards may not be that hard, but pumping water maybe.

Re: Starting in Reverse?

Posted: Wed Jul 15, 2015 3:51 am
by AusAnzani
Charles uk wrote:I think you ought to type "Honest" at the end of that post!
:lol: :lol: :lol:

Re: Starting in Reverse?

Posted: Thu Jul 16, 2015 7:56 pm
by headdownarseup
Sorry Charles

"Honest"


honestly, that old toyota never did run backwards after that episode.
Confused the toyota mechanics as well (honestly)

:lol: :lol:


Honest Jon (lol)

Re: Starting in Reverse?

Posted: Fri Jun 17, 2016 6:37 pm
by smutts
It can be done with diesels with in-line injector pumps.
At least I managed it reverse bumping a three cylinder lister engined dumper. Honest. I still have the mental scars, ten degrees of frost, three plungers of SAE30 oil, (glow plugs, wot they?) and using that starting handle (don't they go a LONG way if they stick!), gave me some more.

The seagull might be possible, but if so, the spark if existant, would be well retarded.

Re: Starting in Reverse?

Posted: Sat Jun 18, 2016 11:17 am
by Collector Inspector
Starting Reverse........how Cool!

Not a Gull sorry as pointed out above......coz they have a magneto made to go the Tuther Way.

If a motor single cyl two stroke has a battery ignition......another story. I had a Vespa when I was very young.....not that long ago really.....it backfired and ran backwards at the drop of a hat.....well 1966 or something that I am not willing to admit to just now?

HONEST!

If an Anzani with a dynastart with battery ignition.......yes. They are something else again yeh? The ignition was designed for that though.

BnC


EDIT:

It was a Badged "150 Electric"..........Vespa....Lambretta.....or something..................Battleship Grey with twin saddles anyway......had a spare wheel and tool kit in a flimsy bag.

It was quite poky I remember........

Re: Starting in Reverse?

Posted: Tue Jun 21, 2016 10:15 pm
by chris
had a bultaco 360 pursang motorbike that would start in reverse, very embarrassing when taking off

Re: Starting in Reverse?

Posted: Sun Oct 04, 2020 7:41 pm
by andrew
Did anyone every try this successfully or not? Wondering about this for some time now and just found this old thread.

I had an old 50cc moped with clutch/gears that would run backwards if you roll started it. Even got to 2nd gear once, very wobbly going backwards though! So I know some 2 stroke motors will run backwards.

Re: Starting in Reverse?

Posted: Sun Oct 04, 2020 9:38 pm
by Silver Surfer
I tried it with my Little 40, but it didn't want to know, so I gave up, with a very sore shoulder!

1968 - Traffic Lights changed - My old Lambretta pulled away fine, but my mate, on his BSA Bantam, stalled it, kicked it over in a hurry, and rode backwards into the front of a Bus.
Laugh? I nearly got the drinks in!

Honest!

Re: Starting in Reverse?

Posted: Sun Oct 04, 2020 10:51 pm
by Charles uk
There is the small problem of the spark instead of being 23 degrees before top dead centre, being 23 degrees after on a Seagull rotating in the wrong direction.

Meaning most of the fuel/air charge shouldn't have enough time to combust before the exhaust port opens.

Perhaps someone should try starting a Seagull that runs with points, by using a large reversible electric drill, that will spin it backwards at more than 700 revs.

Re: Starting in Reverse?

Posted: Wed Oct 07, 2020 4:42 pm
by Journeyman
OK firstly there will be no need to say Honest at the end of this!
Most two strokes will run backwards some are even designed to do so.
There are many big marine engines that are coupled directly to the prop shaft with no gearbox involved. Most of the these engines are two stroke diesels with sleeve valves, when the bridge wants to go astern they ring down with the telegraph and the engineer stopes the engine ( it’s very important the engine is stoped) then he pulls a lever that alters the timing of both the sleeve valve and the injection pump. When it is restarted (compresed air on piston) it runs in reverse and the ship goes astern. The only problem with this very simple system is that if the engine is not completely stoped it will continue to go ahead.
Two strokes with piston controlled ports will run backwards if the ignition is advanced until it becomes after TDC then if the engine is spun backwards the ignition becomes before TDC and the engine will run. The Mag running backwards should still produce a spark as the mags will still be pasing the Iron ends of the primary coil and when the points open it will produce a spark.
If you want some stories about the consequences of not getting an engine to go full astern but going full ahead or how I got a 16 cylinder four stroke diesel to run backwards let me know, they will be honest stories :) !

Re: Starting in Reverse?

Posted: Mon Oct 26, 2020 2:37 pm
by John@sos
Been there and done it with my 1958 Bantam! Very embarassing!

Not tried it with a Seagull as yet!

John
SOS