2GM20 decompression levers - correct action

bluerm166

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Can anyone with hands-on knowledge of the 2GM20 please advise the correct position for the levers when normal compression is allowed and the other position at which decompression is activated.
I ask this because I have total travel of each lever between approx 9.30 and 2.30 and the owners manual is unclear. On Page 47 the sketch appears to show that the valve is lowered for decomp by raising the lever to 2.00 (toward stern) whereas on page 49 the sketch apparently indicates the opposite but may be showing how you return the lever during cold starting.Both sketches are made from the same side of the engine.
The workshop manual doesn't include this info.
Would be grateful for any experience.
 
Can anyone with hands-on knowledge of the 2GM20 please advise the correct position for the levers when normal compression is allowed and the other position at which decompression is activated.
I ask this because I have total travel of each lever between approx 9.30 and 2.30 and the owners manual is unclear. On Page 47 the sketch appears to show that the valve is lowered for decomp by raising the lever to 2.00 (toward stern) whereas on page 49 the sketch apparently indicates the opposite but may be showing how you return the lever during cold starting.Both sketches are made from the same side of the engine.
The workshop manual doesn't include this info.
Would be grateful for any experience.

Looking astern if the levers are aft no compression if forward compression, there is no cold start on the 2gm20 it's just open throttle to full start adjust.

John
 
I think the levers should be down, I.e. flat along the top of the cylinders for normal running, so you can swing the engine and literally drop the hammers to start it once it's turning over. In my experience with 2 and 3-GM they work just fine like that.
 
You can easily tell the difference. When the levers are up (valves lifted) you can turn the engine by hand with little effort.
 
Many thanks for your replies.It is the vague annotation in the manual that made me doubt my memory, coupled with the large arc that my levers describe,so as to lie flattish in either direction.Also I have been timid at turning the engine to check compression after it has shown initial firing in case it fires accidentally,but I can see,not being Popeye, that this is pretty unlikely.In fact the workshop manual does show the pair of levers in what I now know to be the normal,compression position.
Thank you all.
 
I have a 2GM and live in Tasmania where the temps range from 0 to 30 degrees C and when starting by the starter motor I just press the button and it will fire and run within a couple of seconds

Hand starting would need the decompression lever activated but for battery starting it is not required

Regards Don
 
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