OMG - lawnmower problem....Right now a very statinary engine...

Briggs & Stratton 3.5 .
Just lost loads of power. Intermittent splutter under no load.
Tried fresh petrol, thorough cleaning of air filter, cleaned spark
plug, fat spark, replaced spark plug. Seems to have plenty of compession.... Oil is clean ( replaced every season and is at correct levels. Does smoke on startup ( well, it always did since new). And now smokes a bit more than I remember... Gummed rings? Any quick and dirty solutions? (i'd have been tempted to bung in some ether to free it up but I remembered that the 2l bottle of ether I had was more than 20 yrs old .. and old ether can decompose explosively. So I disposed of the ether ecologically (pour over weeds gently, move car (I know that was the wrong order now), throw match.. Well, ethers organic isn't it?
The fuelling system is new to me - it seems to have an oil feed into the (carb? drip feed petrol thingy - the carbs on my old Cossack Ur(in)al seem futuristic compared to that...)
Anything obvoius I should check ( I've had almost all my spanners hijacked by my brother for his new motorcycle project - he left me three big imperial spanners, a 22mm deep socket, a torque wrench, my second best impact driver and one set of imperial feeler gauges - he even took my WD40... - teach me to go into into hospital... I'm going to have to go to the auction houses as on past experience I'll never see them again. Why he felt the need to take the Ducati thing extractor I'll never know....)
Bum.
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On Mon, 15 Oct 2007 05:59:44 -0700, Derek Lord Of Misrule!

Sounds like cr*p in the carb.....
Peter -- Peter A Forbes Prepair Ltd, Rushden, UK snipped-for-privacy@easynet.co.uk http://www.prepair.co.uk http://www.prepair.eu
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Thats my current thought... but its being a bit of a b to get off. Did try a quich flush through with solvent... But I expect it'll need a good soaking and blowing through... I suspect photos will be needed to refer to the correct positioning of the springs located above the carb. Which you can see doing interesting wobbly things when youve got the air cleaner off. I suspect I'll find out what they're for after I've lost at least one of them, but honestly, I've seen sturdier springs in a 10p ball point pen.... And I thought paying the extra for Briggs and Stratton was a good choice...
Second best impact driver is due for an outing ... :-)
Or I'll threaten the thing with a lump(hammer)ectomy.... And sell it for spares on fleabay.... Slightly used Champion spark plug from unfinished project (rare).
I'll keep you posted if I find anything of interest...
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On Mon, 15 Oct 2007 08:38:21 -0700, Derek Lord Of Misrule!

Our 10hp B&S has similarly awful fine springs, you need to make sure they are assembled correctly as the speed governing is by air flap on some models if my memory serves me correctly.
I have the B&S master manual here someplace, bl**dy great thick thing that covers most engines (except the one you have just bought!)
Peter -- Peter & Rita Forbes Email: snipped-for-privacy@easynet.co.uk Web: http://www.oldengine.org/members/diesel
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On Mon, 15 Oct 2007 05:59:44 -0700, Derek Lord Of Misrule! wrote:

What colour smoke?
As you've changed adjusted most everything but the carb I suspect that is where the problem lies. On mine there is a diaphragm between the carb and tank that forms several little flap valves and fuel pump driven by the vacuum. I had loss of power, hunting and general not running when one of the flap valves had got out of position/slightly worn. Carefully repositioned the diaphragm and it's been fine since.
--
Cheers snipped-for-privacy@howhill.com
Dave. pam is missing e-mail
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Remove carb/tank assy take off carb blow thro with carb cleaner clean out fuel well in tank ensure gauze on fuel feed is clean reassemble with new diaphragm/gasket clean and reoil(not too much) air cleaner check you've not lost the "O" ring that slides over the intake stub and the plastic keeper ring refit carb/tank assy This cures most of B&S carb problems I do at least 5 a week
Mike.H

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Thanks team, I shall apply your useful and positive suggestions this weekend. Or my mattock...
And by hook or by crook I WILL get it working... Air flap speed governing? Buttocks.. I want my lawnmower to give maximum power - the weeds deserve respect... But I suppose its cheaper than a throttle... sigh.. Off to auction house on Saturday morning to try to replace missing spanners.
My remaining mole grip clone does suffice for many tasks but I do feel wrong using it ....BTW I used to have a triangular shaped screwdriver ( two cross head, one flatty) Very useful - are they still made?
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