[GigglyHz]

Anyone know the clearance settings on an OS 110 4 banger.

The manual states .004mm and .010mm but not which which measurement to which valve.
I presume the .004 is inlet and .010 is exhaust, could someone please verify.

Thanks in advance.

[acook]

Are you sure the 0.004 isn't the inches dimension? ie. 4 thou

because 0.004" = 0.10mm roughly....

[GigglyHz]

Originally Posted by acook

Are you sure the 0.004 isn't the inches dimension? ie. 4 thou

because 0.004" = 0.10mm roughly....

Yes..the manual is definitely in millimeters. Roughly 1.5 and 4 thou'

I have the feeler gauges but no reference as to which valve the measurements refer too.

[Swifty]

I think the clearance on both valves is the same, will check in my OS 120 manual to see what it says. Those measurements are what the valve clearances should be min max.

[controlliner]

The .004 is the lash clearance. The .100 is the max alowable clearance. These are basicly go-nogo guages.

[Cougar429]

I find on most of mine I set the lash at .002".

[Frank Klenk]

Originally Posted by GigglyHz

Anyone know the clearance settings on an OS 110 4 banger.

The manual states .004mm and .010mm but not which which measurement to which valve.
I presume the .004 is inlet and .010 is exhaust, could someone please verify.

Thanks in advance.

The larger clearance will be for the exhaust valve as it runs hotter and the clearance will close up as it does get hot. The smaller clearance is obviously then for the intake. Go by the book and you can't go wrong.

[AJCoholic]

Originally Posted by controlliner

The .004 is the lash clearance. The .100 is the max alowable clearance. These are basicly go-nogo guages.

This is correct. You should be unable to get the thicker (0.1mm) shim under the rocker when cold, but just be able to get the thinner one (0.04mm) in. This will give you somewhere in between the two clearances and that is correct for BOTH valves.

Remember, yo want to be able to just slide the thinner feeler in the gap, but not be able to get the thicker on in.

.04mm is the thinner one (which is 1 1/2 thousandths)
.1mm is the thicker one (which is 4 thousandths)

This is pretty much standard for all brands of model 4 stroke, not just the O.S.

AJC

[AJCoholic]

Originally Posted by Frank Klenk

The larger clearance will be for the exhaust valve as it runs hotter and the clearance will close up as it does get hot. The smaller clearance is obviously then for the intake. Go by the book and you can't go wrong.

Frank, both valves are set the same.

The booklets O.S. include are VERY good, and actually tell you all this. I sometimes wonder why people just don't read them...

Quoted from the manual:

"The standard valve clearance, on both inlet and
exhaust valves, is between 0.04mm and
0.10mm(0.0015-0.004 inch), measured between
valve stem and rocker arm. Use the 0.04mm and
0.10mm feeler gauges to check clearances. "

[GigglyHz]

Thanks for the info gentlemen.

Just had a reply from OS engine support, The measurements are go and no go.



AJChoholic

The booklet supplied with the engine has no information regarding the adjustments, just that you need to purchase a kit and periodically check.

The instructions come with the adjustment kit. I have 5 sets of feeler gauges imperial and metric and didn't want to purchase any extra.