kohler KT 740

[Gerry]

Got a Husky LGT48DXL with the Kohler KT740-3044. Problem dripping oil. Inital look see oil all over electric PTO and a small pool on top of the crank drive belt pulley. Think its a PTO seal pull the engine clean the sump bottom etc sit on blocks. Wait 18 hours lift engine and no oil out of PTO seal or on bottom of sump. Cant find any cracks other than casting marks. Sump seal dont indicate a leak.

Stumped any thoughts?

Edit: Forgot to say I'm gonna hit it with some Dye Penetrant that that will work?

[KE4AVB]

Here I use UV oil dye to find leaks...takes 5 to 30 running time to find most leaks. Now your UV light source needs to the UV dye light wavelength/ Here the dye I use it is 365nm. My UV pen light is boosted so it is brighter than running it on the the AA as the current battery is a 3.7v instead of the 1.5v regular battery. This makes it usable during the daylight hours.

And sometime oil leaks are funny as it depends where the crank stops and the bearings are worn or not. I had one last year that would only leak with the deck engaged.

Using UV dye will definitely save you some time and a lot of guess work.

[Gerry]

Thanks. I have found a minimal leak from around the right drain plug just a small sheen on the bottom of the sump. Question do you think that when the engine is running the crank rotation could induce a strong enough vortex to pull the oil over and then seep down to the pulley?

Thanks again.

[Arkie]

The uv dye the Ke4 mentions is a good thing.

I've seen both the Briggs and the Kohlers not leak oil at all until the oil gets warmed or hot from a running engine.

You will most likely have to set the engine back onto the frame and bolt it down with couple of bolts and do a run leak test with UV dye. (so as to get an exact leak detect) You also need to be careful and not attempt to overtighten a oil drain plug to stop a seep or the block will crack at the threaded boss. Use teflon tape on the plug and limp wrist the plug.

I have done the same as you, remove engine and the PTO seal not be the source of the leak.
Usually a sump gasket needs replaced, but I've also found casting hairline cracks.

[KE4AVB]

Plus seals can leak on the outer contact area; not just the lip to crankshaft area.

And oil can be suck and blown to other areas. This why UV dye is a great tracer as you looking for brightest light indicated leak. A few years ago on a horizontal shaft pressure washer just at the oil leak you would swear it was the flywheel side seal leaking but I ran an UV dye test and found it leaking at the oil fill cap. Now I did leave in the dye and that was a good thing as the same pressure washer came back leaking oil again but this time no UV dye leak indicated so it was the pump seal the second time that failed after the initial repair.

[Gerry]

Run the engine for 45 minutes (no load) here are the UV dye results. Pic#1 Left drain plug while running. Pic #2 right drain plug while running. Pic#3Engine cooled and on bench. Pic#4 Where the oil had traveled while running. Gonna tape the plug see if that stops it. Again thanks to yall. Much appreciated.




https://photos.app.goo.gl/H96u7j1U8F4b6KhU9]

[Arkie]

If it still leaks with teflon tape the aluminum is cracked.

Had to get one welded awhile back that has similar leak.

Another hint. If you cannot get the dye color off for a re-test just clean the area good and use some flat black hi-heat paint over the old dye and test.
The paint can be cleaned off later with lacq or acetone.

Sometimes when the UV dye dries onto metal the dye cleaner will not clean it off for a re-test to see if the leak is repaired therefore the use of paint over the old dye. .