*%$#&^* Oil Filter

GearHead36

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A cautionary tale about oil filters.

I bought a used mower a little over a year ago. The engine had oil leaks at the valve covers. I fixed that and a few other things. Got it back together, changed the oil & oil filter, and used it last season. About an hour & 45 minutes per week. At the beginning of the season, it ran great, cut great, and no leaks. At about the 2/3 point in the season, it started using oil. I thought. Then, close to the end of the season, I noticed that it was actually leaking oil. Luckily, I check the oil before every use, so I just topped it off every time. After the end of the season, I realized that it leaked even sitting parked. The mower is a commercial Cub Cadet with a Kohler EZT750 engine. I like the mower. It does a good job, but engine access could be better, and the engine weighs about 100lbs. I'm over 60 with a bad back, so there's no way I'm able to just lift the engine out of the engine bay. Pulling the engine solo is something of a job, so I decided to wait until after the end of the season, and do it when I did my annual maintenance. I pulled the engine, and found the oil leak. It was the oil filter, which was also Kohler. It had loosened. I had tightened it up just like I do automotive oil filters (snugged by hand), and those get tighter by the next oil change. I've never had an automotive oil filter loosen up on me in about 45 yrs of changing oil. This one loosened, and made a mess. It could have destroyed my engine. So now I'll be checking my oil level AND my oil filter before every use.

This was the 2nd time I pulled the engine, and I AM getting faster at it. If I need to pull it this coming season, I won't wait till the end of the season.
 

ILENGINE

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More common on Kohler filters than people realize. I see 1-2 every year that I had installed by hand just like you and by the next spring tuneup are leaking and can be removed with two fingers. Kohler had issues a few years ago with filters coming loose from the factory. Had to due with how the O ring is installed at the filter factory and had manufacturing oil trapped under the gasket. Briggs must of been having the same issues a couple of years ago also because they now have a torque spec for the filter. Depending on where you look it is 87-100 lb/in.

Changed oil in my Kioti tractor back in April of last year. and after running 40 hours started leaking. Had to take the filter another 1/2 turn with a wrench to stop the leak. Pulled the filter shortly thereafter and replace it.
 

GearHead36

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More common on Kohler filters than people realize. I see 1-2 every year that I had installed by hand just like you and by the next spring tuneup are leaking and can be removed with two fingers. Kohler had issues a few years ago with filters coming loose from the factory. Had to due with how the O ring is installed at the filter factory and had manufacturing oil trapped under the gasket. Briggs must of been having the same issues a couple of years ago also because they now have a torque spec for the filter. Depending on where you look it is 87-100 lb/in.

Changed oil in my Kioti tractor back in April of last year. and after running 40 hours started leaking. Had to take the filter another 1/2 turn with a wrench to stop the leak. Pulled the filter shortly thereafter and replace it.
So should I be using a different oil filter? If so, which one?
 

ILENGINE

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I started using my torque wrench set at 100 lb/in a couple of years ago, and haven't had a loose filter since. The recommended torque spec is tighter then what one gets by tightening by hand. Have always used Kohler filters and the loose filter issue seems to be hit and miss, but seems to always occur on the same mowers every time.
 

GearHead36

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I started using my torque wrench set at 100 lb/in a couple of years ago, and haven't had a loose filter since. The recommended torque spec is tighter then what one gets by tightening by hand. Have always used Kohler filters and the loose filter issue seems to be hit and miss, but seems to always occur on the same mowers every time.
What kind of oil filter wrench to you have that will fit a Kohler filter, and mate to a torque wrench?
 

hlw49

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We have received some isolated reports of oil seepage/leaking at the base of the oil filter. The condition is usuallynot evident until the engine has been run.The filter manufacturer uses oil as a lubricant when the end cap is crimped into the filter canister. In some cases,excess oil was captured in the groove when the gasket was installed. The oil would form a hydraulic lock underthe rapid tightening/compression speed of the assembly line air wrench, giving a false indication that the filterhad reached proper torque. From the heat and vibration of operation, the oil will thin and begin to seep out of thegroove, allowing the gasket tension and joint to relax. The oil from the groove may seep to the outside, and oilmay also leak past the relaxed gasket joint.If a complaint is received, or a Kohler-powered product is being set up/serviced in your shop, the oil filter shouldbe checked to ensure that it is sufficiently tight. The recommended installation procedure is hand-tightening3/4-1 turn after the rubber gasket contacts the adapter. The tension on the gasket is applied more graduallyduring hand tightening, so any oil in the groove has a chance to escape. The filter manufacturer will also stampfour V-impressions in the inner groove ring, so oil can escape to the inside, even during machine tightening.As we reprint owner’s and service manuals we will change the recommended hand-tightening from 2/3-1 turn to3/4-1 turn after the rubber gasket contacts the adapter. Torquing the oil filters is no longer recommended, so thetorque value of 10-13 N·m (90-110 in. lb.) will be removed
 

GearHead36

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We have received some isolated reports of oil seepage/leaking at the base of the oil filter. The condition is usuallynot evident until the engine has been run.The filter manufacturer uses oil as a lubricant when the end cap is crimped into the filter canister. In some cases,excess oil was captured in the groove when the gasket was installed. The oil would form a hydraulic lock underthe rapid tightening/compression speed of the assembly line air wrench, giving a false indication that the filterhad reached proper torque. From the heat and vibration of operation, the oil will thin and begin to seep out of thegroove, allowing the gasket tension and joint to relax. The oil from the groove may seep to the outside, and oilmay also leak past the relaxed gasket joint.If a complaint is received, or a Kohler-powered product is being set up/serviced in your shop, the oil filter shouldbe checked to ensure that it is sufficiently tight. The recommended installation procedure is hand-tightening3/4-1 turn after the rubber gasket contacts the adapter. The tension on the gasket is applied more graduallyduring hand tightening, so any oil in the groove has a chance to escape. The filter manufacturer will also stampfour V-impressions in the inner groove ring, so oil can escape to the inside, even during machine tightening.As we reprint owner’s and service manuals we will change the recommended hand-tightening from 2/3-1 turn to3/4-1 turn after the rubber gasket contacts the adapter. Torquing the oil filters is no longer recommended, so thetorque value of 10-13 N·m (90-110 in. lb.) will be removed
The above oil filter was installed by hand. If this problem has only been observed when using air tools, that doesn't explain what I experienced.
 

shurguywutt

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Thanks for the heads up @GearHead36 - I just put a new filter on mine and like you, I tightened it by hand because that is what I have always done with autos. I haven't had a chance to run it yet because it is still too cold. Now I will make sure it is sufficiently tight before mowing starts this year. I put a Rotary brand filter on mine but regardless I will check it out.
 
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