Riding lawn mower boiling hot oil, add oil cooler?

About once a week I blast out everywhere I can with compressed air. It stays pretty clean. Any thing that does get in gets chopped up by the fan.
It does burn about a quart of oil between changes.
I am cutting knee high tumble weeds.
A little bit less invasive thing I could try is put a 12 inch fan fan on the hood and force more air over the engine and in the engine bay. Might try that first. I have a fan laying around, fuses, breakers, switches, wire in my junk collection. I guess if the magneto can keep up with the fan it could work.
Blowing out isn't going to get the debris out from under those shields. Only way to really clean is to remove them to clean the fins.
 
The higher horsepower Kohler came with an oil cooler. An adaptor goes between the engine block and oil filter. I sourced one on evil pay. Remove fan shroud and cut a ~ 4" square hole to mount the radiator. I blow out the engine fins after every mowing and the oil cooler fins 3 to 4 times per year.
 
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The overheating issue on my 81 MTD is fixed. I ran it for an hour plus today with no issues, before you could feel the heat surrounding the hood. Besides the mice filling the cooling fins they also ate the ignition coil wire which is how I got it for free. New coil which deleted the points and it runs like new.
 

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I took off the screen and pulled some covers to see what was behind them and it wasn't much.
I added the fan to force air into the top cowling and it seems to work. The control panel would get hot from thr recirculating engine heat, now the panel stays ambient temperature and the additional clean air seems to keep dust out of the engine compartment. The magneto has no trouble keeping up with the fan.
 
I took off the screen and pulled some covers to see what was behind them and it wasn't much.
I added the fan to force air into the top cowling and it seems to work. The control panel would get hot from thr recirculating engine heat, now the panel stays ambient temperature and the additional clean air seems to keep dust out of the engine compartment. The magneto has no trouble keeping up with the fan.
Any pics?
 
Boiling water only says the oil is at or above about 212°F. That's why they specify a 40 or 50. I'm thinking they designed it right, take a sample and send it in, see if the oil is holding up. What is the recommended change interval?
Who’s They?

Here is the owners manual. Lots of Bitoggers run 40 grade but run what you like. An oil cooler is not required. Air cooled engines are designed to run hot.

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Shell Rotella T6 in 5W-40 is my go to oil for lawn tractors, and a lot of other things...

You may be able to oversize the oil filter, a Wix 51516 is my choice...
 
Rotella has a weak addictive package now it's all modernized for catalyst engines.
Have to run the SH, SG retro oil that will plug up a catalytic converter.

The boiling point of water is 204F here.

My son found my inferred temperature gun, I can do temperature tests. Fan off vs fan on. I'll paint a flat black target on the oil filter for accurate results.
 
Shell Rotella T6 in 5W-40 is my go to oil for lawn tractors, and a lot of other things...

You may be able to oversize the oil filter, a Wix 51516 is my choice...
Right now I have a botch d3330 on there with some marine 20w-50 oil flowing through it that has so much zddp it stinks. I'm pretty sure my usual filter is a wix 51516. It's a wix with a bypass, about 3 to 4 inches long. The briggs and stratton standard filter is like 2 inches long.
 
I use M1 10-30 in my OPE which includes my Craftsman 21HP rider. The oil appears to be fine with nothing noticed that would indicate a problem. OCI is every 2 years and the oil is always a nice amber color with no oil consumption.
 
I have a John Deer F510 with a Kawasaki ~13 hp. It's a engine hydraulic unit and they share the same oil but not the same sump. When i first got it and first changed the oil it was way hot. I measured the temp later on with a long probe into the dipstick hole after a 2 hr mow in +90F and it was near 300F.

So I got a bypass sandwich adapter and put a ATX oil cooler on it, not tube and fin. Temps now are seldom over 220F. I put in a temp gauge too. At first I tried some 4 and 6 tube and fin coolers and they didn't hardly drop the temp. But this kind did.

Hayden cooler.jpg
 
I got the sandwich adaptor in. I'll probably stick it on and at first just use it as a gauge probe holder. Then decide what size oil cooler based on the temperatures I see.
 
I deleted my post last night because I had not looked before posting it.

The V-Twin Kohlers I have are 24HP Pro engines. They are factory equipped with oil coolers. These are vertical engines, if you are using the carburetor as the rear, the oil cooler is mounted on the right hand side towards the front of the fan shroud, there is a cut out in the shroud that allows the fan to blow through the cooler. So a cooler on these is nothing new.
And actually post #22 above mentions the same thing, and where the cooler connections are located at the oil filter base adapter.
And for post #33 just find a parts book and you have your cooler you desire.
Actually a quick check on Amazon shows them and the adapter together.
 
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I have a second riding lawn mower now, I had it since last year, I got it as a pile of parts. And just got it cutting grass this week. It's a 19hp single cylinder, 46 inch deck. It doesn't get nearly as hot.
 
You may be able to loweer the temp a bit by just switching to Redline. I have 15w50 street (non-racing)
RL in my Kawi, seems to run a bit cooler (15-20 degrees) with that, than with mobile-1.
 
When I first put the tube and fine coolers on I also tried a 12v fan but still didn't hardly drop the temp. With that small Hayden I don't see anything over 220F even when near 100F ambient.

What I don't know is the shared hydraulic section oil temp. As it is somewhat separated I believe based on the fact I cannot drain all the oil out but only about 2/3s. I can tell when the oil gets +210 hot the ground speed seems to drop a bit..
 
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