engine backfires

[scout279]

I have a 25hp Kohler on my 60" ZTR. Had a new short block put on this past winter and ended up having some throttle issues. So I had a new fuel pump put on and needed to replace the valve cover on the oil fill side. Now its a couple weeks later and for the last week periodically it will sound like I am trying to make popcorn. It doesn't do it all the time but it is frequent. Not exactly sure what I should look at first. I am trying to not take it back into the shop since they will take a few days to look at it. Can't afford the down time. Any help would be appreciated.

[TURF DOCTOR]

Adjust your valves

[scout279]

Ok being that I feel like I might sound ignorant but I have no idea how to do that. Is it somthing easy or should I just have the shop do it.

[Lawn-N-Garden Guy]

A good Equip.Dealer should have a loaner till yours is repaired.I do most of my repairs myself but times like these it ok to pay your dealer for repairs and being able to drive away with a demo model at the same time.Less down time

[fixer67]

Adjust your valves

Most CH25 and CV25 Kohlers have self adjusting hydraulic valve and you MUST use 10W-30 oil or the lifters will chatter. First I would check the spark plugs. The wrong plug or a carboned up plug can cause this. We use RC12YC or RC14YC plugs in all our Kohler enignes