Kohler CV15s idles choked, backfires and dies off choke

dan5003

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  • / Kohler CV15s idles choked, backfires and dies off choke
Kohler CV15s idles with choke on, then as you take it off choke and tries to run a little faster, it starts backfiring and dies. Has new spark plug, spark looks good, carbs been cleaned, gas is clean, coil gapped at .010. Started up and worked fine after sitting for the winter, then when I tried to start it and put it away it had the problem. I did a compression tested and got 190 after a few spins. Not sure what else to check. I don't know much about this stuff, so any ideas are welcomed.

Dan
 

mechanic mark

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  • / Kohler CV15s idles choked, backfires and dies off choke
Air filter clean, fuel filter ok? You need fresh fuel, air, spark, & compression to start. Have you checked valve lash?
scroll down page to CV15S service manual
See section 11 page 11.15 for valve lash adjustment. If valves are out of adjustment compression release on camshaft will not assist in starting.
See Figure 11-37 on page 11.12 Cylinder Head Valve Train Differences, one side non-adjustable & one side adjustable.
 
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dan5003

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  • / Kohler CV15s idles choked, backfires and dies off choke
Air filter clean, fuel filter ok? You need fresh fuel, air, spark, & compression to start. Have you checked valve lash?
scroll down page to CV15S service manual
See section 11 page 11.15 for valve lash adjustment. If valves are out of adjustment compression release on camshaft will not assist in starting.
Thank you very much for a link to the service manual. I'm not qualified/certified to service these, just trying to see if I can learn enough to fix my old mower. Thanks to your input I've watched a few videos on doing the adjustment. In section 11.15 it say to use a .07/.12 mm (.003/.005 in.) feeler gauge.

Does that mean .003 for intake and .005 for exhaust?
And is the exhaust rocker the one pictured at the top in the 11-45 photo?

I think knowing these answers should give me enough info to try the adjustment.
 

Scrubcadet10

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  • / Kohler CV15s idles choked, backfires and dies off choke
Some CV15's use hydraulic lifters and there is no manual clearance adjustment.. post the Spec number from your engine identification tag.
to answer your question, generally the larger clearance is for the exhaust valve.
 

bertsmobile1

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  • / Kohler CV15s idles choked, backfires and dies off choke
Thank you very much for a link to the service manual. I'm not qualified/certified to service these, just trying to see if I can learn enough to fix my old mower. Thanks to your input I've watched a few videos on doing the adjustment. In section 11.15 it say to use a .07/.12 mm (.003/.005 in.) feeler gauge.

Does that mean .003 for intake and .005 for exhaust?
And is the exhaust rocker the one pictured at the top in the 11-45 photo?

I think knowing these answers should give me enough info to try the adjustment.
No it means greater than .003" and less than .005"
Or if you like .004" +/- .001"
 

dan5003

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  • / Kohler CV15s idles choked, backfires and dies off choke
Some CV15's use hydraulic lifters and there is no manual clearance adjustment.. post the Spec number from your engine identification tag.
to answer your question, generally the larger clearance is for the exhaust valve.
Spec number is 41526
 

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Scrubcadet10

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  • / Kohler CV15s idles choked, backfires and dies off choke
Yep, that engine uses hydraulic lifters so there is no adjustment for valve lash
1619219316981.png
 

bertsmobile1

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  • / Kohler CV15s idles choked, backfires and dies off choke
Either the carb has not been cleaned properly or the engine is sucking air after the fuel has been added .
Check that the solenoid under the carb is fully retracting.
Debris & Varnish gathers there and prevents the plunger fully retracting .
 

dan5003

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  • / Kohler CV15s idles choked, backfires and dies off choke
Thank you, I really appreciate the advice. I'll check the carb and plunger next.

I've attached a photo. I never found a gasket on the cover. Thought I would need to purchase one to put it back on, but now I'm wondering if had some sort of liquid gasket or something.

What do you guys use, and where to you get it, to put it back together, a gasket or a tube of something? Just want to make sure I'm doing everything right.
 

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bertsmobile1

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  • / Kohler CV15s idles choked, backfires and dies off choke
YEs you are correct
That model Kohler uses silicon on the rocker cover
I cut a gasket to go in there because I hate spending hours cleaning old silicone off parts before I can reassemble them.
 
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