Can you bump start a boat?

[jimi]

If your battery was flat could you get a tow, get the prop spinning in neutral then if you banged it into gear, would the engine start?

<hr width=100% size=1>

 

[snowleopard]

i was warned that if i used self-pitching props they could bump-start the engines at high speed. the speed quoted was 17 knots+

so if you got a tow behind a mcgregor 26.....

<hr width=100% size=1>

 

[BrianJ]

Only in the height of passion
BrianJ

<hr width=100% size=1>BrianJ

 

[Robin]

We once had a problem with a Bukh 10 on a Liz 30 where the engine stop sometimes went too far and in order to restart it you had to spin the engine very fast to reset the injection rack and get it started, faster than sometimes the battery could manage alone. I forget the details now but you somehow knew after shutting the engine off that it was 'wrong' and we would need to restart it and shut it down properly ready for instant use later. The way we discovered worked was to spin the engine on the starter with the decompressor open and then put the engine into gear whilst sailing at speed (even did it under spinnaker), dropping the decompressor would then usualy restart it ok. We eventually had the injector pump serviced and the problem was solved.

<hr width=100% size=1><font size=1>Sermons from my pulpit are with tongue firmly in cheek and come with no warranty!</font size=1>

 

[bedouin]

At a guess - no. I doubt if there is enough energy stored in the prop/shaft to turn the engine.

<hr width=100% size=1>

 

[Clive_Rigden]

I've bump stopped a boat.

But there again, I would have wouldn't I . . . ?

<hr width=100% size=1>Khyber

 

[ccscott49]

No!

<hr width=100% size=1>

 

[fireball]

The only method I've heard of to "bump" start an engine is

Wind a long line around the flywheel/crank (where ever possible)
Tie a bucket on the other end
Get the boat sailing as fast as possible
Throw the bucket over the back (assuming your going ahead!)

Unless you tie another line to the bucket, you'll loose it along with the line, and it would probably be a good idea to put a block in a suitable place to help direct the line (rather than chaffing the companionway)

If leaving it in gear would help or not I don't know - but doubt it, more assistance would probably be to use the decompression levers to let the engine spin up before fireing.



<hr width=100% size=1>

 

[StugeronSteve]

Only if you can find a big enough hill to push it down.

<hr width=100% size=1>Think I'll draw some little rabbits on my head, from a distance they might be mistaken for hairs.

 

[MOLLYdownUnder]

You can Bump start a Hercules, saw it a few times whilst serving in RAF, use jet wash from laed aircraft to start props of rear a/c and then light blue touch paper and retire.
regards Nick

<hr width=100% size=1>

 

[TheBoatman]

I wouldn't have thought that it was possible just by towing the boat but if I found myself in the back of beyond with no hope of help and had to "try" to start the engine I would probably attempt something like this.

First attempt to wind a rope around the crank pulley (v.difficult)

Then pull the boom in (no sail up) so that it was above the companionway and using a line and block fix it to the boom above the engine pulley.

Run the crank line up through the block and attach it to the genny clew.
Using a sacrificial piece of line tie a rolling hitch between the genny sheet and the winch.

Start to sail hard on the wind with all lines tightened.

Cut the sacrificial line and let the genny do its work.

I have no idea if this would work or not but it might be fun trying. The next problem is, if the battery is completely flat the chances are that even if you start the engine the alternator won't charge until you can get 12v across the exciter wire?

<hr width=100% size=1>

 

[MOLLYdownUnder]

Molly has a Yanmar 20 diesel and comes standard with a hand starter, decompress and away you go, shouldnt all marine engines have this facility?
regards Nick

<hr width=100% size=1>

 

[claymore]

Yes
Mr Curwen who lived on Belle Isle on Windermere used to own an amphibious Triumph Herald.
I have it on good authority that he once bump started it on the hill in Bowness.

<hr width=100% size=1><font color=purple>regards
Claymore<font color=purple>
/forums/images/icons/smile.gif
http://www.whoi.edu/services/facilities/CLAYMORE/

 

[MOLLYdownUnder]

PLEASE UPDATE YOUR BOOKMARKS....

THE CLAYMORE OWNER'S WEBSITE HAS MOVED TO:

http://www.whoi.edu/services/facilities/external/people/CLAYMORE/index.htm

Hey Claymore Please keep up to Date!!!!!!!!!!!!!!!! & more recently Isnt the Claymore also a Land Mine?

Regards Nick

<hr width=100% size=1>

 

[andy_wilson]

Only if you had a huge flywheel attached to a very free spinning propellor (these two items are relative to each other and the engine size).

An indestructible gearbox would help, but if the flywheel were VERY large you could try getting it in gear with de-compressors on then releasing them to start.

Engines with an exposed flywheel have been started mid-ocean by use of a rope leading to a controlled gybe.

<hr width=100% size=1>

 

[BlueSkyNick]

Where SWMBO comes from, (Bermuda) MollyDownUnder would be considered a rude name.... Molly is child-slang for a part of the female anatomy.

<hr width=100% size=1>I can't be bothered with a footnote - it's usually rubbish anyway.

 

[ParaHandy]

Re: Can you bump start a beneteaux?

hmmm ....

what do you call a bene with a bimini? A skip ...

how do you double the value of a bene? fill the fuel tank ..

what's the difference between a bene and a tampon? one's got a tow-rope

bene owner asks if dealer has a rudder for a bene? sounds like a fair swap says ancaster ...

what's the difference between a bene and a sheep? it's less embarassing getting out the back of a sheep ...

why's a bene got a rudder? don't know but someone might ....

<hr width=100% size=1>

 

[MOLLYdownUnder]

Hi Molly was shipyard built in Durban and originally called GOGOK which is Africaan for Tin Can .......hence the name change!
regards Nick

<hr width=100% size=1>

 

[claymore]

Hmm
I'm not one who can do internet things like websites so if it changes it was done by an American Lady.
Claymore landmines are indeed as you describe - there is also an Ice hockey team - the americans seem to like changing things.

<hr width=100% size=1><font color=purple>regards
Claymore<font color=purple>
/forums/images/icons/smile.gif
http://www.whoi.edu/services/facilities/CLAYMORE/

 

[Wiggo]

Why not press the link switch, and start it from the other engine's start battery? Or use one of the domestics, or the bow thruster/windlass battery, or the start the genny..?

Anyway, I thought you were going nuclear/electric, Jimi?

<hr width=100% size=1>Si hoc legere scis, nimium eruditionis habes.