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Collection, Preservation and Display of Old Lawn Mowers

decompression valve

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Hi again. Very sorry if i appear to be hogging these pages of late.Having recently retired,i find i am attending to two or three mower at once instead of the weekend hobby that it used to be.

My question this time concerns the decompression valve on my Standard 16.Most people will already know the answer but i confess i don't. Will the engine start whilst the valve is open ?.I assume it will close automatically when the engine fires. It seems an easy question,but i've been pulling my arm out of its socket by disregarding the valve and i'm sure there must be an easier way.

Once again,many thanks.

Forums

wristpin Mon, 05/05/2014

There's an operators manual on this site under Lawn Mowers, Technical Help , Mower Makes, Atco Operating Manuals, Atco Standard.pdf   but you have to stand your screen on its side to read it!!! 

It covers the starting procedure using the decompressor .

topgunhorse Tue, 06/05/2014

I'm assuming your decompression valve is working? As long as the valve is closed tight with the spring that is built into it, you can just leave it closed while trying to start the mower. I use mine for stopping only.

Many similar engines don't have one, eg the HY

olcadmin Tue, 06/05/2014

Thanks for highlighting the link the operating manual wristpin.

Don't forget, in most browsers, you can rotate the pdf to fit your screen. In IE or Chrome, simply right-click to show a menu of options and then choose the rotate clockwise or anti-clockwise.

If you download the document, all of the main pdf readers have a rotate function which is normally accessed on the menu bar. Web browsers don't normally have that which is why you need to right-click when viewing it online.

olcadmin Tue, 06/05/2014

If you pull the lever to the horizontal the slight cam on the mounting should ensure it stays in position. Once you get the engine turning over you can flick the lever to release it. The spring will close the valve and, assuming all else is correct, the engine should fire. I too use the lever to stop the engine.