valve adjustment oddity wrong cam?

[joeyg1973]

So I am finishing up and doing the valve adjustment

1,2,3,5,7...wtf...,9...wtf.

I have it in tdc according to the line on the flywheel, but the pushrods on 7 and 9 are up. The cam shaft is in correctly as I did line up the two dots on the timing gears... I don't know what could be the issue. Any ideas?

Joe

 

[Big B.]

turn the crank 180 degs

 

[Trollhole]

x2...

 

[joeyg1973]

Yeah but then the 1 piston would be 180 degrees out of tdc... I have the timing mark on the flywheel set right and the 1 piston has hit my tdc stop in the spark plug. According to all the instructions I have read it's 1 in tdc, adjust 1,2,3,5,7,9 rotate 360, adjust 4,6,8,10,11,12.

I guess I am confused as to why it isn't working per instructions and I need to rotate 180?

 

[joeyg1973]

I hate it when I am impatient and don't RTFM.

Use your timing mark to reset the timing when you are done. If you use just the timing mark you can be 180 dregees off.

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I don't get why this is though.

 

[Pin_Head]

I don't get why this is though.

It is because it is a 4 stroke engine and there are two TDCs for each cycle. One is TDC on compression; the other is TDC on the exhaust/intake strokes. Both valves are closed on the compression stroke.

 

[joeyg1973]

It is because it is a 4 stroke engine and there are two TDCs for each cycle. One is TDC on compression; the other is TDC on the exhaust/intake strokes. Both valves are closed on the compression stroke.

Yeah brain fart... BTW it's 360 on the crank, 180 on the dist.