Volvo 2003 decomp lever

svaha

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Hi,

The "new" boat has a Volvo penta 2003. I just been poking round familiarizing my self with the engine and...

There doesnt appear to be a decompression lever. After a bit of surfing I have found some online manuals which appear to show it where you'd expect ie on the cylinder head above the fuel filter.

You can see where it ought to be or was: theres a "fitting" still there.

Has it been removed? Why? Were any 2003s made without a decomp lever?

Help!


cheers
martin
 
I would imagine there should be a decompression lever as it is used as the emergency stop on the 2000 series engines that i have seen. Personally i would order the parts from key Parts (very reasonable and helpful) and fit it.
Rgds
Bob
 
The decompression lever has to be removed to get the valve cover off. I'd imagine it's possible that the lever on your engine just got lost and someone filled the hole in where it should be.
 
I'm sure your right but perhaps I should qualify the term "fitting" above.

Its clearly designed to block the hole in the cylinder head where the lever should be (its just a flush circle of metal), so its not like the fitting of a lever would be straight forward.

I am more interested in why the lever isnt there...is there a story or can or worms lurking?


cheers
m.
 
If you take the valve cover off, you should see the decompression shaft above the camshaft. It's supported in the camshaft bearing brackets. If that's there, all you need is the lever and the O-ring which fits round it.
 
I had a 2002 in 1987 which was seawater-cooled but had to be replaced about 5 yrs later. It was replaced by a freshwater-cooled engine which had neither a decompression lever or hand start. I imagine all the 2000 series from around then had been changed.
 
Kermudjon: interestingly mine is fresh water cooled but does have hand cranking...i havent tried this without decomp as I like the discs in my spine to be disc shaped:)

pvb: you make it sound so easy...i wish i had the nerve to give it a go!


cheers all
m.
 
As far as I remember, from 10 yrs ago, the procedure was - half throttle, pull the stop lever & release, and then start. My 2nd engine ran for about another ten years and we had very little trouble starting.
 
I did hand-start my first 2002 occasionally, for practice in case I needed to. I believe the only difficult thing was racing out into the cockpit to turn the throttle down went it started. I used to do it single-handed and I'm not particularly strong, though I imagine the 2003 would be harder.
 
Svaha
Can't remember exactly if anything clutters up the access to the rocker cover. But, undo the bolts on top of the cover and gently prise the cover off, a gentle tap with a blunt instrument might help. Be careful not to damage the joint between the cover and the cylinderhead. All will be revealed underneath. Refitting is the reverse, just remeber not to overtighten the bolts when you put it back.
Hope this helps
Rgds
Bob
 
That is the normal procedure for starting these engines. But if you tried pulling the stop lever with the throttle open the probability is the engine wouldn't stop. Maybe they altered the internal linkage in the later models so they would.
Rgds
Bob
 
I've just had our 2003 reconditioned, and if the decomp lever is in the vertical position, there is no compression on any cylinder, and therefore the engine can/will be stopped.

If it is fully to the left/starboard, only one cylinder is in service - two are decompressed.

Fully to the right/port, all cylinders are in service.

Download engine manuals from here

or here
 
With a slice of luck and a warmish engine the 2002 can be hand started. The 2003? Unlikely, unless your name's Clark Kent.

Flywheel's too light, being the main problem.
 
Hi,

I really only wanted to decompress to turn the engine over by hand as I have a long held superstition that this moves the oil round and does other magical things to make the engine start nicely and never wear out:)

Perhaps I should just get over this:)

Thanks everyone for the responses, this has been really very helpful...


cheers
martin
 
It would take a couple of revolutions of the engine under starter motor to get the oil pump delivering significant oil flow. Under hand turning it might be possible to get the pump to operate but in general I suspect the leakage back through the pump would be greater than the flow rate that it could deliver.

However, even if flow was established it would only lubricate the bearings, which are perfectly OK standing still without any lubricant. Lubricating the bores and pistons is achieved by oil splash from the gudgeon pin, and even the aforementioned Clark Kent would have difficulty in doing that by hand cranking. Getting any oil to the cylinder head, cams and tappets would also be a very long job under hand cranking.

It is really best to fully winter the engine at the end of the season and then don't touch it until you need it again in the spring. Running it briefly during the winter to 'see if it's OK' is probably the worst thing you can do for it, so don't be tempted by that one either /forums/images/graemlins/smile.gif
 
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