Just weird... (pontificating garden tractor stuff- and thankful for a dipstick)

[LEAKYSEALS951]

Today, I went to fix my John Deere x728. It has a kawasaki engine on it. I wish it were diesel, but the kawasaki's seem to last at least 700 hours before engine issues occur.

I've had it for 6 flawless years, and it only has about 350 hours on it.

In the recent weeks, I've had it parked outside to haul wood during the recent cold. Temps here got around 0-15 degrees, and I would go out and start it and let it warm up to get wood. Temps weren't crazy low, but were cold enough that it would just click the solenoid, and just barely get the engine to turn over. Once started, it would run fine (well- begrudgingly since I had left it outside and it was pissed at me).


Last week, it started missing bigtime, like bad gas. I only run ethanol free, with preservative, but the tractor had been outside, and the tank was near empty, so I naturally assumed some moisture had gotten into the tank, and sucked into they system.

No Biggie. However- when checking things today, I was LESS THAN HAPPY to find the oil level at 2x full!!!! WTF?????

Immediately, I was thinking blown gasket, but the radiator was not low. Then I was thinking stuck injector with gas getting past the rings, but the plugs (if anything) were fouled with carbon. Although the plug picture looks soaked, most of it is dried flaky carbon buildup. They were not soaked. Also, the oil (I like to light things on fire) was not flammable, which I would assume with gas it would be.

The oil itself was not frothy, but something wasn't right. It was a watery brown, not an oily brown. There were bubbles on top of it (like water/gas droplets floating at the surface). It smelled more like gasoline/varsol than oil, and had lost most of it's viscosity. It poured like ATF/water more than like oil (10w-30). I also only run mobil synthetic, and change it yearly. It had less than 30 hours on it. It has a no nonsense dipstick on it and it burns nothing and has been very consistent to date.

The tractor is also very weathertight. I don't see how snow/ water would have gotten into the gas or the oil directly from being left outside.

I immediately changed the oil, and upped the viscosity to some spare 15-40, so if something was leaking/thinning the oil, I would have a thicker baseline oil to start with. I only filled to the bottom mark as well, to give room to see if it creeped up.

The engine still missed, but after replacing the plugs seems to run fine now. The oil is as clean as could be, and the tractor seems happy. The oil level is not rising. Everything seems ok.

What would cause that? I can't see how I would overfill it by several quarts. It made me think those meddling kids snuck up to the house and ovefilled it with varsol. But that's just the mind of a paranoid curmudgeon. Thoughts?

[LEAKYSEALS951]

Now I'm wondering if I did overfill it (I still don't know how that would happen) and the extra oil frappachino'ed the viscosity out of it. Now I am wondering if I am going senile?
Perhaps the computer dispstick would be better?

Oh hell no!!!!

[wdfifteen]

That spark plug looks like it’s been running very rich. The most likely culprit for that much increase in oil volume is water intrusion.

[LEAKYSEALS951]

^ and that's what get's me overthinking these things- for example, could the high oil level cause the crankcase vent to suck in more oil gumming things up, or would failing spark plugs look like that.

I did clean the air intake (it was filthy), but even running with no air filter did not affect missing.

[pete3799]

Does your motor have an electric shut off on the fuel bowl? If it sticks open it will fill the crankcase
with fuel.

[KFC911]

Remember when I bought a JD for my dad a few months ago....the PO gave me 2 quarts of oil which I immediately changed. His quarts were 48 oz. though

You're not as stupid as I am are ya ?

[LEAKYSEALS951]

^Thanks. Your idea got me internet searching, but, then I remembered, this is fuel injected, so it looks like it has a FPR valve and return line to the tank instead of a regular fuel bowl, so I might be wrong, but it doesn't look like it has one. While looking up your idea, I found a VERY detailed factory service manual to date on the model. It's much more detailed than anything else I have ever seen- so Thanks.

https://www.slideshare.net/ssuser2018be/john-deere-x728-lawn-amp-garden-tractor-service-repair-manual-77343928

Also- in regards to wdfifteen's water idea. I agree. The tractor always smells like antifreeze when it's hot, and today was subjectively strong, but it never seems to lose coolant. It's something that has always made me wonder, and has been going on for years. I might have added a dribble since I bought it (2-4 oz?) tops.

Today I got the tractor up to operating temps several times to pressurize the system to see if it would spring a leak. If anything, the oil level has settled down a tad. Still clean as can be.

edit- I also checked the new plugs. It really is running rich, but the new plugs are strong/hot enough that they haven't fouled yet. They are putting up a good fight.

Fingers crossed.

[Bob Kontak]

Originally Posted by pete3799

Does your motor have an electric shut off on the fuel bowl? If it sticks open it will fill the crankcase
with fuel.

I see this on the Cub Cadet. Worth looking into. There is a simple fix to this. Research.

However, an entire carb assembly will not break the bank.

[LakeCleElum]

To determine if fuel or coolant got in your oil, pour some on concrete or pavement. The coolant will bead up........Fuel will not.

[wdfifteen]

Originally Posted by LEAKYSEALS951

Also- in regards to wdfifteen's water idea. I agree. The tractor always smells like antifreeze when it's hot, and today was subjectively strong, but it never seems to lose coolant. It's something that has always made me wonder, and has been going on for years. I might have added a dribble since I bought it (2-4 oz?) tops.

Pour the drained fluid into something clearish. A gallon size plastic water jug should work (cut the top out of it). Water will separate from the oil and settle to the bottom. It will be obvious if it's there. Make sure you look at ALL the fluid.

[fastfredracing]

I left my splitter sit out last season. I tarped it up good. Started right up last fall, but within about 5 minutes of running, it started to smoke, and blow the dipstick out. I was sure I rusted a cylinder , or burnt a valve.
It was way overfull of oil. Did not smell like gas, and looked like water intrusion .
I think I wrapped it up too good, and made a terrarium out of it, and the moisture ended up in the crankase.
I changed the oil, and ran the heck out it this fall, and it works perfect.

[pen15]

Engine oil mixed with coolant/water that has been run in an engine for any amount of time will not separate. It is emulsified like mayonnaise.

[wdfifteen]

Originally Posted by pen15

Engine oil mixed with coolant/water that has been run in an engine for any amount of time will not separate. It is emulsified like mayonnaise.

Nope. Maybe a LONG period of time, I don’t know, but I’ve had experience similar to Fred’s, and never run an engine long enough to turn the oil to mayonnaise.

[LEAKYSEALS951]

Thanks all!
Once again I'm amazed by how much I learn on this site.

I went ahead and did the concrete test- no bubbles today (yesterday it seemed like bubbles everywhere).
I shook the oil up, and drained into a glass jar. I'll let it settle out and see how the bottom looks.
I wouldn't be surprised if at least some moisture got into the oil from starting/ not letting boil off/ stopping during the cold cycles.

Oil still at same level, but the tractor REEKS of antifreeze when running. It always has, but this seems worse, yet coolant tank level unchanged.

[DanielDudley]

It's kind of weird, but my WRX never seems to use radiator fluid, but sometimes smells, while my GMC never smells, but uses fluid. It doesn't take a lot of vapor to smell, but you can have a much harder time detecting an internal leak, except of course by level.

I bought a lawnmower one time with a crank case full of oil and water. Changed it out and it never came back.