Valve lash adjustments

[yugo]

Valve adjustment on a Farm Pro 2425 with a Y385 engine, 300 hour preventive maintenance on a rainy afternoon, and this is what we found. The book that came with the tractor said that adjusting the valves was a three step procedure. ( I can relate that to a 3 can project) The first can was to remove the valve cover and locate top dead center on number one. I found the marks on the fly wheel, and also on the front dampener pulley. Can #2 is to adjust the valves. Number one - A-OK. The book says to rotate engine crank shaft 180 degrees, and check number 3 cylinder. Somewhat tight. The book says rotate the crank shaft 180 degrees to cylinder number 2. Valve adjustment here waaay tight. Somethings wrong! Now we see it must be Can #3 step. Stop and recheck top dead center. Check that we're turning the engine the correct way. Still the cam shaft geometry is off. Can #4 - Stop and think about it, to find what's wrong. In the bottom of this can, we found the answer. The cam shaft dials in at 240 degrees, instead of the 180 degrees. At 240 degrees of crank shaft rotation per cylinder, the valve adjustment came out A-OK. Has anyone else had this experience?
P.S. Not just anyone can take a 3 can job and stretch into a 6 pack job! Yugo

 

[JINMA224XR]

Hello Yugo,

We had an extensive discussion on Valve Adjustment in the Y380T Engine section at "NYTO FORUM SITE".

You might find it interesting to read.

Have a nice day,
Joe

 

[F100Panel]

I have a little easier on the brain method for adjusting the valves but admittedly it requires more time & turning of the engine.. I work 1 cylinder at a time. When I see one valve start to open as I turn the crank, I know the other valve on that cylinder is in the closed position/proper time to adjust. Takes longer but no brainpower required... Just my lazy method for adjustment/likely not the best/easiest... /forums/images/graemlins/smirk.gif

 

[schmalts]

Heres what you do. While rotating the engine in the normal direction (crank engine to see what that is, follow these steps.
when the exhaust valve is just starting to open adjust the intake. when the intake valve is just starting to close, adjust the exhaust. This will have the valves checked at base circle

 

[johnk]

That's how I do mine. It is much simpler, quicker and runs fine.

 

[schmalts]

</font><font color="blue" class="small">( I have a little easier on the brain method for adjusting the valves but admittedly it requires more time & turning of the engine.. I work 1 cylinder at a time. When I see one valve start to open as I turn the crank, I know the other valve on that cylinder is in the closed position/proper time to adjust. Takes longer but no brainpower required... Just my lazy method for adjustment/likely not the best/easiest... /forums/images/graemlins/smirk.gif )</font>
You do not want to do it that way, there is some overlap in valves and if you do the intake when it is just starting to open you will be adjusting the exhaust when it is still open or just barely closed.

 

[F100Panel]

Shmaltz- TRUE/AGREED/just starting to open should be valve basically open. To the human eye ( especially an older eye..) The valve has to be REALLY open to see it... & also not mentioned, the push rod of the other valve has no pressure on it & you can spin it with your finger freely. THANKS /forums/images/graemlins/wink.gif for getting me to fully explain.... & Actually, watching for the open valve to begin closing to adjust the other valve is a darn good idea too....

 

[thingy]

Which valve is which?,,some require different gaps,[exhaust/intake],if both the same than no problem,like my 254,,but pretty sure some 204's are different,as probably are others. thingy

 

[awlchu]

A trick I learned working on my motorcycles is to buy a "go-nogo" step feeler gauge. Each blade is precision grounded with the tip being .001" less than the body of the blade. Typically a good set will have a .024/.026" combination on one blade.

Thus the .024" should fit while the .026" should not fit. Helps with the guess work of settting the gaps.

 

[schmalts]

Look to see what port the valve aligns with better. The one in line with the intake port is the intake and so on.