Starting a small diesel, manually...just how hard can it be?

Greenheart

Greenheart

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I've heard that when batteries or starter-motors fail, or if for another reason it isn't possible to turn a small diesel engine over electrically, it can be done by hand.

I've no idea, but I'd like to know whether it's a question of judgement and familiarity with the technique, raw muscle-power, sheer luck, or a combination of these.

Maybe it's worth practicing the manual start, for those days when battery-amps don't oblige? Does anybody prefer their own manual-starting procedure, over electric starting?
 
dancrane said:
I've heard that when batteries or starter-motors fail, or if for another reason it isn't possible to turn a small diesel engine over electrically, it can be done by hand.

I've no idea, but I'd like to know whether it's a question of judgement and familiarity with the technique, raw muscle-power, sheer luck, or a combination of these.

Maybe it's worth practicing the manual start, for those days when battery-amps don't oblige? Does anybody prefer their own manual-starting procedure, over electric starting?
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I have tried to start my 1GM10 by hand and failed miserable. The problem is that I have to stand on the wrong side of the engine and turn it the wrong way through compression which is at the most awkward and inefficient angle possible. I know some people do it, but I am sure they must have a much more ergonomic layout than I have. If it had a decently heavy flywheel then it might be possible to spin it up decompressed, but the 1GM10 flywheel appears to be stamped out of an old tin can.
 
JumbleDuck said:
I have tried to start my 1GM10 by hand and failed miserable. The problem is that I have to stand on the wrong side of the engine and turn it the wrong way through compression which is at the most awkward and inefficient angle possible. I know some people do it, but I am sure they must have a much more ergonomic layout than I have. If it had a decently heavy flywheel then it might be possible to spin it up decompressed, but the 1GM10 flywheel appears to be stamped out of an old tin can.
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Tried it once on our MD11D, this had two decompression levers so swmbo flipped one when I had some speed up. Fired up on one cylinder obviously but I was mid 30's then and quite fit - it nearly killed me :)
 
I don't think anyone hand starts a diesel by choice!

I've started a 1GM10 by hand (reasonable easily but I was in an easy position compared with the previous poster).

I have failed miserably with other larger engines.

The general principle is to put all the decompressors to 'decompress' and spin the engine as fast as you can and then 'drop' one of the decompressors to start it on one cylinder. By yourself it's very difficult but some people manage with a helper and a bit of string to the decompression lever...
 
As said, big flywheels and decompressors. But I have often started small Petters with a cord and a quick flip of the lever. On the farm, with no lecky, the bore hole pump was a 16hp Lister diesel turning 50 mtrs of shaft and the pump. If you didn't get that first time, a 'little' rest was needed.
If the battery is not dead, decompressing and then spinning up on the starter can do it, if there is not enough juice to overcome the compression.

There are hydraulic or spring starters that you compress or wind up by hand. I understand the big RTW boats carry one as a back up.
 
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A round the world SH sailor had flat batteries & suddenly realised that his race was over if he could not start his engine
His answer was to wrap webbing around the flwheel, rig pullies to keep it in line then lead it to the mainsheet of his boat.
When ready he hauled the main in then released it with a bang. The main applied a massive force, pulling on the strap, & engine started
You do need to remember what way the flywheel has to turn but if in trouble I think that I would stand on the coachroof where I could get max leverage with webbing around the flywheel & pull upwards. I suspect that a lot of modern engines do not have decompressors so it makes it harder

Once when broad reaching in a gale in the English channel I went below & found that the engine was inexplicably ticking over. I can only think that as I surfed down a wave (I was regularly doing over 11Kts) I must have kicked the gear lever from neutral & effectively bump started the engine. I had left the fixed bladed prop spinning freely so when i kicked the lever it suddenly engaged the gear & flipped it over
 
In days gone by, when small Volvo Penta engines used to be supplied with starting handles, I tried to start mine by hand. Total fail - even using the decompression levers!
 
I used to have to do this regularly with our old BMW D7 with no decompressor. It could be hard work. In some ways I'm quite glad to see that its successor, a Beta 10, has nowhere to apply a starting handle.
 
pvb said:
In days gone by, when small Volvo Penta engines used to be supplied with starting handles, I tried to start mine by hand. Total fail - even using the decompression levers!
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A mate used to start his engine by attaching a string to the decompression lever, turning it over using the starter motor, then whack the lever in when the engine was turning quickly. Claimed it saved something. Not sure he did it manually though.
 
pvb said:
In days gone by, when small Volvo Penta engines used to be supplied with starting handles, I tried to start mine by hand. Total fail - even using the decompression levers!
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Snap to that on a Bukh DV36. After spinning up, dropped the compression lever and the whole thing stopped still. Didn't even feel I was getting close. Bl00dy hard work as well!

Chas
 
I've tried starting my Volvo 2001 by hand with one person on the 'starting' handle and one on the decompressor. We didn't stand a chance. Since there is no flywheel, as soon as the decompressor was flicked, the engine stopped turning. If you don't use the desompressor, the engine just turns in a series of stop/starts every time it hits TDC. I think it's the lack of a flywheel that makes it impossible.
 
Dipper said:
I've tried starting my Volvo 2001 by hand with one person on the 'starting' handle and one on the decompressor. We didn't stand a chance. Since there is no flywheel, as soon as the decompressor was flicked, the engine stopped turning. If you don't use the desompressor, the engine just turns in a series of stop/starts every time it hits TDC. I think it's the lack of a flywheel that makes it impossible.
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The flywheel will be the starter ring on its aft end all small engines will have one to even out / damp the compression stroke
 
You need a good standing position, a good handle, "easy start" spray, and a good technique. Also to avoid braking the bones of your thumb, you need to tack your thumb in with the rest of the fingers, ie the handle must not be between the thumb and the fingers or you will loose your thumb when/if the engine kicks back. Virtually impossible to hand start yacht engines as there is no much space to get a good footing.
 
Easy Start :sleeping:
This is what the Australians use
SYBcanLOWjpg_resized_240_-1.jpg
 
Dipper said:
I've tried starting my Volvo 2001 by hand with one person on the 'starting' handle and one on the decompressor. We didn't stand a chance. Since there is no flywheel, as soon as the decompressor was flicked, the engine stopped turning. If you don't use the desompressor, the engine just turns in a series of stop/starts every time it hits TDC. I think it's the lack of a flywheel that makes it impossible.
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The 2001 does have a flywheel, but it's enclosed. It weighs about 20kg, so not as heavy as some conventional flywheels on older engines.
 
I've also tried this once or twice with my MD2B - getting it up to speed with the flywheel with the decompression levers up and then dropping just one I can just about manage 2 compression strokes - nothing like enough to start from cold.

the very first boat I owned had a single cylinder Coventry Victor that could only be started by hand but that was a much smaller beast.
 
Hand-starting a modern engine, which has a much lighter flywheel that is not even readily accessible, is bound to be very difficult if not impossible.

I can still manage it on my old (1973) MD2b. The usual reason why people fail is that they flip the decompression lever before the flywheel is turning rapidly enough. I turn the starting handle, as fast as I can, until I am almost out of breath. When that stage is reached is when the lever is flipped, not before.
 
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