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Valve/Rocker arm setting

Harley Dixon
 

What's the accepted way to adjust the valve lash?  Lycoming instructions say to set the cylinder at TDC, then check or adjust the rocker arm/push rod gap (solid lifters...it's an O-235 C) but wouldn't it be easier to rotate the prop until the intake valve is approaching fully open then set the exhaust valve rocker arm gap, and vice versa for the exhaust valve settings? That's the way I used to do it for my cars before hydraulic lifters. Looking around the internet, I don't see any mention of doing it this way on solid lifter aircraft engines.

Harley
Long EZ N28EZ

Virus-free. www.avg.com

longezn911gg
 

Harley,
You want to pre-load #2 and #4 then start with #1 at TDC set it to .008” +/-.001 then continue in the firing order. After you have completed it go around once more re-checking with the feeler gauge. There is a you tube video on the 0-290, which is the same. Always refer to the lycoming manual.

Good luck 

Craig Gearhart


On Jun 30, 2020, at 12:09 PM, Harley Dixon <harley@...> wrote:


What's the accepted way to adjust the valve lash?  Lycoming instructions say to set the cylinder at TDC, then check or adjust the rocker arm/push rod gap (solid lifters...it's an O-235 C) but wouldn't it be easier to rotate the prop until the intake valve is approaching fully open then set the exhaust valve rocker arm gap, and vice versa for the exhaust valve settings? That's the way I used to do it for my cars before hydraulic lifters. Looking around the internet, I don't see any mention of doing it this way on solid lifter aircraft engines.

Harley
Long EZ N28EZ

Virus-free. www.avg.com

Steve Beert
 

Harley look at your Data Plate My O235 L2C Data plate says .010 but like Craig’s states look in the engine manual also. 

Steve Beert


On Jun 30, 2020, at 12:04 PM, longezn911gg via groups.io <longezn911gg@...> wrote:

Harley,
You want to pre-load #2 and #4 then start with #1 at TDC set it to .008” +/-.001 then continue in the firing order. After you have completed it go around once more re-checking with the feeler gauge. There is a you tube video on the 0-290, which is the same. Always refer to the lycoming manual.

Good luck 

Craig Gearhart


On Jun 30, 2020, at 12:09 PM, Harley Dixon <harley@...> wrote:


What's the accepted way to adjust the valve lash?  Lycoming instructions say to set the cylinder at TDC, then check or adjust the rocker arm/push rod gap (solid lifters...it's an O-235 C) but wouldn't it be easier to rotate the prop until the intake valve is approaching fully open then set the exhaust valve rocker arm gap, and vice versa for the exhaust valve settings? That's the way I used to do it for my cars before hydraulic lifters. Looking around the internet, I don't see any mention of doing it this way on solid lifter aircraft engines.

Harley
Long EZ N28EZ

Virus-free. www.avg.com

Harley Dixon
 

Thanks. That what what I was going to do (using the Lycoming Service Instruction #1068A), but I was hoping that there would be a bit shorter and simpler way!  I have nothing but time now anyway, so no problem!

Harley


On 6/30/2020 1:04 PM, longezn911gg via groups.io wrote:
Harley,
You want to pre-load #2 and #4 then start with #1 at TDC set it to .008” +/-.001 then continue in the firing order. After you have completed it go around once more re-checking with the feeler gauge. There is a you tube video on the 0-290, which is the same. Always refer to the lycoming manual.

Good luck 

Craig Gearhart


On Jun 30, 2020, at 12:09 PM, Harley Dixon <harley@...> wrote:


What's the accepted way to adjust the valve lash?  Lycoming instructions say to set the cylinder at TDC, then check or adjust the rocker arm/push rod gap (solid lifters...it's an O-235 C) but wouldn't it be easier to rotate the prop until the intake valve is approaching fully open then set the exhaust valve rocker arm gap, and vice versa for the exhaust valve settings? That's the way I used to do it for my cars before hydraulic lifters. Looking around the internet, I don't see any mention of doing it this way on solid lifter aircraft engines.

Harley
Long EZ N28EZ

Virus-free. www.avg.com

Harley Dixon
 

Thanks Steve...already checked mine.  Lists them as .007 to .009. So .010 is a no go, and .008 is a go IMHO.

Harley


On 6/30/2020 1:36 PM, Steve Beert wrote:
Harley look at your Data Plate My O235 L2C Data plate says .010 but like Craig’s states look in the engine manual also. 

Steve Beert


On Jun 30, 2020, at 12:04 PM, longezn911gg via groups.io <longezn911gg@...> wrote:

 Harley,
You want to pre-load #2 and #4 then start with #1 at TDC set it to .008” +/-.001 then continue in the firing order. After you have completed it go around once more re-checking with the feeler gauge. There is a you tube video on the 0-290, which is the same. Always refer to the lycoming manual.

Good luck 

Craig Gearhart


On Jun 30, 2020, at 12:09 PM, Harley Dixon <harley@...> wrote:


What's the accepted way to adjust the valve lash?  Lycoming instructions say to set the cylinder at TDC, then check or adjust the rocker arm/push rod gap (solid lifters...it's an O-235 C) but wouldn't it be easier to rotate the prop until the intake valve is approaching fully open then set the exhaust valve rocker arm gap, and vice versa for the exhaust valve settings? That's the way I used to do it for my cars before hydraulic lifters. Looking around the internet, I don't see any mention of doing it this way on solid lifter aircraft engines.

Harley
Long EZ N28EZ

Virus-free. www.avg.com