the engine is back firing out of the muffler after it runs for a few minutes .. while cold runs fine.. cranks easy too.. one cylinders is fouling a plug.. I checked the compression on both cylinders the good one is at 180 the side fouling the plug was 175 I replaced both coils about a year ago .. any ideas would be apricated...
Could be a blown head gasket. Though I am not that familiar with the CH series of the Kohler engines I am with the CV and have lots of them with blown head gaskets. A blown head gasket will not show up in a compression test. It will not how up in a cylinder leak down test or a crank case vacuum test. The gaskets blows between the oil return hole and the cylinder and is so small it just will not show up in any of these test. The best indication of a blown head gasket is a fouling plug.
HLW .. thank you for your reply.. I am helping my dad with this problem.. he called earlier today.. told he me took the ohv cover off said he could move both rocker arms a little sideways.. the bolt holding both were tight .. took the other side off both rocker arm had no side movement on them.. anything to that? I do remember he changed that head gasket on the fouled side about 5 years ago.. when it went bad it maked a very loud sound .. you could actually see the plug firing between the cylinder and head...
Wow have never seen one that bad. When they blow out side the cylinder you can hear then whistle at you while starting and shut down. Could have a very slight side to side movement in the rockers. But like I said more familiar with the CV since that is what comes on the mowers we sell and most of what we service.
Again thanks for replying.. I talked to him and he told me this.. this started when noticed excessive smoke in the exhaust... he checked the oil and found a lot of raw gas in the oil .. so he replaced the carburetor thinking it might fix it.. now no gas in the oil..but it still backfires??
Back fires When? While running or on shut down? When he had the rocker covers off did he happen to turn the engine over and watch to see if the valves were opening and closing as they should?
it backfires after it runs a few minutes .. then might run a minute.. then do it again.. it never backfires when you turn it off... no he did not check that..
49 we found a blown head gasket and the valve were leaking .. we ordered a new head assembly with valves and gaskets. do we need to lap the new head and valves???
49 we found a blown head gasket and the valve were leaking .. we ordered a new head assembly with valves and gaskets. do we need to lap the new head and valves???
thank you for your reply it also includes new push rods and rocker arms... we were thinking of replacing lifters to.. do think they could be damaged to? we were thinking about the age of them??
They are fairly cheap or have been in the past, so replacing them at this time would be fine. Sometimes they can get some weird wear patterns which could cause issues later.
I thank you for your help.. wish you were close by.. the closes shop we have to repair the engine is 40 miles from us.. our toro has a 62 inch deck we don't have a large enough trailer for it. could I ask one more thing about it.. the liters are there any tale tale signs about a bad liter in an engine.. again thanks for your valuable help...
A tapping noise when running could point to a faulty lifter that has collapsed or the tapping could be due to the lifter not rotating properly causing the camshaft lobe to wear a groove in the bottom which will cause an intermittent tapping when the groove aligns with the lobe and sounds like the rods are coming loose.
A tapping noise when running could point to a faulty lifter that has collapsed or the tapping could be due to the lifter not rotating properly causing the camshaft lobe to wear a groove in the bottom which will cause an intermittent tapping when the groove aligns with the lobe and sounds like the rods are coming loose.
we finished the repair today... the head gasket was blown old style on it... we also found out the exhaust valve was bad it was very hard to move up and down after we removed the valve springs .. badly charred on the back of the value and inside the valve guide...thanks to all of you for your valuable help... we thought about doing the other side... but the plug looked good ... your thoughts on that..
