3GMF Hand Crank

[Uricanejack]

Just collected my boat out of yard last weekend and went for my first sail on her.
Before we could get going I had to borrow a battery and jump start the engine as batteries were way down after a month on the hard.
Unfortunatly the boat does not have a crank. I was wondering if any one knows if you can get a hand crank for a Yanmar 3GMF looks like I would need a fitting on end of shaft to attach crank as well.
Looks like there is room to turn crank some boats have crank but no room to turn.

 

[Contest1]

My 3gm30 Is raw water cooled and has a hand crank awkwardly placed but mannagable.
Even with the help of an experienced dumper driver we couldn,t start it last year when the batterys failed.
Just wondering if its worth all the trouble.
I now carry a small 31ah gel, originaly bought for my electric outboard, that starts the engine no bother and holds the charge for months.
Just bought new 100 ah batteries so hopefuly have a belt a braces system giong forward.

 

[yoda]

I may be wrong but I don't think the fresh water cooled Yanmars can have a hand crank fitted, the raw water cooled ones do. I think you would be better off with a dedicated engine battery and a solar panel to keep it topped up. I have had this arrangement for many years and never any trouble.

Yoda

 

[charles_reed]

My 3gm30 Is raw water cooled and has a hand crank awkwardly placed but mannagable.
Even with the help of an experienced dumper driver we couldn,t start it last year when the batterys failed.
Just wondering if its worth all the trouble.
I now carry a small 31ah gel, originaly bought for my electric outboard, that starts the engine no bother and holds the charge for months.
Just bought new 100 ah batteries so hopefuly have a belt a braces system giong forward.

Both raw-water cooled 3GM and 2GM had provision for a starting handle.
Unfortunately this was at the end of the camshaft and on a 1:2 gearing from the crank - even with the decompressors lifted it was almost impossible to turn over the 2GM that I had (I did it once but that was under the influence of terror and never managed it again).
For that reason, even if your 3GM is raw-water cooled, I wouldn't even consider it.
I fitted another battery after that incident!!!

 

[Salty John]

The 3GM30F has two holes in the flywheel into which you insert two bolts. Then you can use a winch handle across them to turn the motor over. It would take a lot of practice and much luck to get this all to work properly, I concluded.
By using the decompression lever you can get the engine spinning on a tiny residue of battery power, then drop the lever, and off she goes. Never failed for me when I'd contrived to run the batteries down at anchor.

 

[Spyro]

I'd be a bit more bothered about the batteries. A month on the hard shouldn't be a problem if your batteries are in good condition.

 

[Bosun Higgs]

Just collected my boat out of yard last weekend and went for my first sail on her.
Before we could get going I had to borrow a battery and jump start the engine as batteries were way down after a month on the hard.
Unfortunatly the boat does not have a crank. I was wondering if any one knows if you can get a hand crank for a Yanmar 3GMF looks like I would need a fitting on end of shaft to attach crank as well.
Looks like there is room to turn crank some boats have crank but no room to turn.

You would be lucky to turn it. I had a 2GM or was it my 1GM with hand cranking facilities and despite being a bit of a bloater I could stand on the cranking handle and the engine wouldnt turn. On the other hand in 25 years of boating I have never had a flat battery or an engine fail to start. Cars dont need hand starting, why boats?

 

[Spyro]

You would be lucky to turn it. I had a 2GM or was it my 1GM with hand cranking facilities and despite being a bit of a bloater I could stand on the cranking handle and the engine wouldnt turn. On the other hand in 25 years of boating I have never had a flat battery or an engine fail to start. Cars dont need hand starting, why boats?

I can spin my 2gm20 quite easily with the handle as long as the decompression levers are open. Wouldn't you spin it up to speed then drop the levers?

 

[markhomer]

And if your starter is goosed, i have an old spare working available from a 3gm30f

 

[vyv_cox]

I can spin my 2gm20 quite easily with the handle as long as the decompression levers are open. Wouldn't you spin it up to speed then drop the levers?

I would be very interested to hear whether you can get this to work. With an older engine with a big flywheel, like a Bukh, there is plenty of momentum to keep it going when you drop the decompression levers. The flywheel on more modern engines is small and I suspect the compression would be too much to allow the pistons to pass TDC.

 

[Spyro]

I would be very interested to hear whether you can get this to work. With an older engine with a big flywheel, like a Bukh, there is plenty of momentum to keep it going when you drop the decompression levers. The flywheel on more modern engines is small and I suspect the compression would be too much to allow the pistons to pass TDC.

Never actually tried but I should give it a go

 

[ghostlymoron]

Cars dont need hand starting, why boats?

With a car you can call the AA

 

[Blueboatman]

I carry a spare starter for 30GMf.
It is the first marine engine I have owned that clearly is not, realistically, a hand starter!
Maybe one could fire it up from decompressed on one cylinder using flywheel momentum and a blowtorch up the air intake using the residual battery charge but better to have alternative charging methods IMO, cheap petrol genny, two battery banks, solar, wind charger, what have you ...

 

[earlybird]

When I had a 2GM20 I tried hand starting on a number of occasions, warm and cold. Never came near to succeeding.
I had good access to the handle and I regarded the engine as a good starter.
A assistant to operate the de-compressors might have helped, but I wouldn't be too confident of that.
My earlier YSE8 however was a reliable hand starter, although I needed a lie down afterwards!

 

[Spyro]

I would be very interested to hear whether you can get this to work. With an older engine with a big flywheel, like a Bukh, there is plenty of momentum to keep it going when you drop the decompression levers. The flywheel on more modern engines is small and I suspect the compression would be too much to allow the pistons to pass TDC.

Tried today and you're right, couldn't do it. Perhaps with my adapted handle that I can get 2 hands on and someone else to operate the decomp' levers it might have been possible.

 

[ghostlymoron]

I used to start Wingett dumpers by hand when I worked on site. I'm not sure what engines they had but they had a substantial flywheel which kept going once it was up to speed then, drop the decompressor and away you go. However, that was 40 years ago - I don't think I could do it now.

 

[Uricanejack]

Thanks for the replies. this is the first boat I have had with a Yanmar 3GMF. I've sailed other boats with simmillar sise diesel which could be hand started quite easly.
I did try turning over with decompresion levers open no luck batteries to low. Looks like the concensous is 3GMF is not easy to hand start.
The fly wheel is quite small compared to others. I have have hand started.
As a boy I used to hepl start an old Kelvin 8 cylinder by hand.
Big fly wheel. open all the compresion levers, started turning slowly, gradualy worked up to speed, Closed no one cylinder, and she would start then close the rest one at a time.
So a back up battery may be a better option.
Pitty, the ability to hand start and you are never stuck.
Or what the heck its a sailboat. I can always sail home.

 

[Tranona]

Hand starting dates from the days when small boats had no - or unreliable electrics. Many of the engines originated in industrial use where again electrics were not available. Therefore they were designed with heavy flywheels and decompressers as it was the only way of getting them going. This type of construction limited revs and power and resulted in heavy, noisy engines.

Modern diesels are a fraction of the weight and size and part of this is achieved by using lighter flywheels and power gained by higher revs. This of course leads to greater refinement and the ability to fit more powerful engines in smaller boats. What makes all this work is the improvements in electrical equipment which means starting is no longer an issue in a well maintained boat. So there is little point in compromising design to provide something that is largely unnecessary. As already suggested a dedicated engine start battery and a means of paralleling the house battery is the way to go.

 

[ghostlymoron]

' As already suggested a dedicated engine start battery and a means of paralleling the house battery is the way to go.'
Noooo . If you parallel a flat battery with a charged battery, you'll get the equivalent of a half-charged battery which may not have enough grunt to start your engine - then what do you do? Instead of paralleling, you need to substitute the house battery. This is easily achieved by appropriate switching.