Yanmar 1GM10 Valve Clearances

Severnman

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About to do this job on this engine. Seems straight forward enough, I have manual. Anybody with any useful 'got the t shirt' info - much appreciated. I will be replacing rocker cover gasket - is a non setting gasket sealant also required? Thanks
 
I can't remember the valve clearances.

Just remember to get TDC on the compression stroke. Theres on little hole on the bell housing which you can peer though and should see "TDC" mark on the fly wheel.

When on the compression stroke the tappets should be "slack".

I found its better to do when the engine is cold because everything hasnt expanded with heat.
 
check them cold and the clearance is 0.2mm or 0.008in

nothing really to look out for except when you take the bonnet cover off the rockers are free to slide off so beware of the top hats slipping off the valvetops.



Steve
 
About to do this job on this engine. Seems straight forward enough, I have manual. Anybody with any useful 'got the t shirt' info - much appreciated. I will be replacing rocker cover gasket - is a non setting gasket sealant also required? Thanks

Rocker clearance is 0.2 mm (8 thou) and should be set cold. I can't find anything in manual about sealant for the rocker cover. I'm not going to bother.
 
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agree about the top hats, i used to use an inspection mirror to see the timing marks

the rocker cover gasket is nothing more than posh brown paper but it's an awkward shape to try and cut from gasket paper so just bite the bullet and buy a new one
 
Experts please check my valve clearance idea!

My installation is so tight that I have no way of finding/seeing an inspection hole for the timing mark. The other option is to remove the starter says the service book. Also not too appealing.

So what I did was to rotate the crank until the intake valve was obviously opening. I then adjusted the exhaust valve to 0.02. I rotated further until the exhaust valve was opening and adjusted the intake valve to 0.02.

Is this an ok way of doing valve adjustment? Or is there a specific reason to adjust with the cylinder in top dead centre?
 
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