[deaddeere420]

How do you guys read engine RPM to set the governor speed?

I put my tach on my engine and it read 6000 RPM
I tried to set it like the book and couldn't get the engine to run under about 2000 rpm

The book calls for 1250 and 3400 full throttle
I set my wide open much lower and I had about half throttle movement

Then I remembered reading that the Onan fires every cylinder rotation unlike a care engine that fires every other one.
Wouldn't this make my tach read twice as high?

Meaning I needed to divide the RPMs in half. This would explain the high RPMs

Or am I missing something?

 

[jameszmcnelley]

hi John, if you have an automotive tach. set to read a 4-cyl. divide in half.
a 4-cyl, 4-stroke engine fires 2 cylinders every other revolution. since your engine fires every revolution, the reading shown is doubled. later, J.Z.M.

 

[deaddeere420]

Great!
Thank you

I thought so
Couldn't sleep last night and it finally dawned on me that was the problem

 

[deaddeere420]

And now that I have had a minute to think about it

Does any one know the reasoning for the firing during the exhaust stroke?

 

[KB]

it is easier to just let an engine fire every time it get to TDC. engineering a skip into it is more complex.

 

[ab318]

The spark at the exhaust stroke don't disturb anything.
A lot of motorcycle like my Suzuki GS1000 was like that.
It's the same for the Honda GX670 in my 318.

The reason is simply because the ignition system is at the crankshaft to save space and/or money.
Also they need half the amount of coils but those coils have 2 wires.

For the Onan it's probably to save one coil.
Andre

 

[deaddeere420]

Thanks for all the answers guys
This board is great

Now I can undo the mess I made

I should have followed the old adage:
"If it ain't broke, Don't fix it!"