Onan 4000 valve lash specs?

Valve Stem to Rocker Arm
0.0008 0.0032
0.0008/0.0032
Clearance (Valve Lash)
(0.02) (0.08) (0.02/0.08)


about to see if this helps...

i am a small engine mechanic by trade. i see it all the time on atv's. kawi's will tighten themselves up and will not start at all and arctic cats will loosen up easy and be slow to start.

it works both ways. to tight and a valve will never fully seat... affecting compression.
too loose will actually affect valve timing if the valve doesn't open and close close enough to when it should.

my onan has ALWAYS been hard to start. never fails to start but takes way to many revolutions for my liking.

CloudDriver wrote:
A quick Google search for your generator came up with this spec sheet. No valve lash info there, but a phone # for Onan if you want to go to the horse's mouth.

In looking at the model #'s listed, I see the same model (4KYFA26100) that is on our 2003 Onan Microlite generator. The valve lash specs for ours are 0.8/3.2 thousandths.

Can't think of a reason why valve lash would cause hard starting, but I'm open to learn something new.

It can if it's to tight.

http://www.cumminsonan.com/www/pdf/manuals/981-0530C.pdf
Here you go.

A quick Google search for your generator came up with this spec sheet. No valve lash info there, but a phone # for Onan if you want to go to the horse's mouth.

In looking at the model #'s listed, I see the same model (4KYFA26100) that is on our 2003 Onan Microlite generator. The valve lash specs for ours are 0.8/3.2 thousandths.

Can't think of a reason why valve lash would cause hard starting, but I'm open to learn something new.

If you don't get the manual, mine says 0.002" cold, which is darn small. When I did it I had a heck of a time getting the lock nut tightened without messing up the lash setting.

model # 4KYFA-6747L

thanks so much!

I can send or post the service manual if you give me the full model number and spec letter.