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Troybilt Superbronco 46 inch deck with 20 HP Kohler Courage - massive oil leak

#1

J

jbeazell

hello all,

I have a massive oil leak that came up out of nowhere over the last two mowings. After the first, I found that all the crankcase bolts around the front of the engine were lose. Not lose, like backed out a millimeter or two and finger lose. I tightened them down, but, the leak is still there.

Before I look into a new gasket, or tear downs, is this common and is there a common bolt that might be in there that I didn't see that came out or lose?


#2

B

bertsmobile1

If that is a single cylinder Courage, you will gave a crack down the exhaust side of the crank case near where the cylinder meets it.

Kohler were doing warranty replacements but this problem is very old now and claims may have closed, you will need to check with Kohler.

I have done a dozen or so with mixed success.
The crack will grow till it gets to the bottom and leak a lot of oil and in the worse cases, cause a loss of impulse signal to the fuel pump.
You can drill 1/4 past the end of the crack to stop it then use your favourite putty.
You can torch weld it
You can mig weld it

I torch weld ( DHC 2000 ) them in situ , took a while to get it down pat.
Whatever you do , wash out the front bolt holes and the bolts then refit with some medium strength loktite


#3

J

jbeazell

If that is a single cylinder Courage, you will gave a crack down the exhaust side of the crank case near where the cylinder meets it.

<sigh> that's sad news. I'll tear into it tomorrow morning to see how bad it might be :)

This makes a little sense since the thing just SUDDENLY started throwing up oil. gasket leaks don't get that bad that fast :)


#4

J

jbeazell

Just FYI, I've confirmed that there is a nice crack starting from the top going down on the front to the left of the head (as viewed from the front of the engine).

I'll try to stop the crack and fill it with JB weld. I suspect that it won't hold too well because of the speed of how quickly this crack showed up. It was only in about 1 to 1 and a half hours of operation from no leak to spitting out oil.


#5

B

bertsmobile1

IT will work to an extent depending upon how bad the original crack was.
Make sure you drill a hole about 1/4" about 1/4" past the visible end of the crack.
take the belts off and you can leave the engine in place.
Off with the flywheel , stator then top plate.
clean the crack really well, carb cleaner followed by acetone.
Roughen the area to give the JB a key the fill the crack & hole put the top plate back on and do it up tight.
leave it for a full day then remove the top plate clean off all the debris, smooth the JB clean & reassemble.
Clean out the bolt holes and then use a few drops of BLUE locktite on the front bolts.

Before you do anything, contact Kohler with your engine's serial number.
Some will get a replacement short block but it will have to be done through a dealer so will cost you some money.

JB seems to hold up pretty well.
It weeps a bit ( well all mine have ) but some I did 4 years ago are still running quite fine apart from the fact they weep up to a pint of oil from under the patch between services.
One is used by a sports club and mows about 3 acres of the outfield weekly during in season.

From here on in, make sure you check the oil regularly and check the bolts eash season when you remove the blower housing to clean the fins at the end of season.


#6

J

jbeazell

Before you do anything, contact Kohler with your engine's serial number.
Some will get a replacement short block but it will have to be done through a dealer so will cost you some money.

JB seems to hold up pretty well.
It weeps a bit ( well all mine have ) but some I did 4 years ago are still running quite fine apart from the fact they weep up to a pint of oil from under the patch between services.
One is used by a sports club and mows about 3 acres of the outfield weekly during in season.

From here on in, make sure you check the oil regularly and check the bolts eash season when you remove the blower housing to clean the fins at the end of season.


thanks ;) I'm not going to put too much more money into it. I got it used year, and the plan was to get something new this upcoming spring. I just need it to last for about another few months of this season and into next.

It is interesting to see that yours held so well. My repair seems fine, but I have a new problem :)


#7

J

jbeazell

Thank you all for your help on this. I JB welded the crack, and did a test run, and it seems to hold pretty well. I also coated the inside of the block with Utra Black RTV. I don't know if that will help but it seems fine and holding strong. The engine has a soft tick now, so I wonder if something happened when the top bolts were lose. It shouldn't be the valves, since I did the valve adjustment while I had everything off.

I have a new related issue. The top gasket has blown out. The entire thing was torqued correctly, and a thin coat of ultra black on top and bottom of the gasket, and all bolts red-loctited. This happened bout an hour into my yard yesterday, and seemed to get progressively worse, so it didn't all spit out at once. I couldn't see it under the plastic cover, so I can't be sure how it progressed.

Now, I'm assuming that the block and top cover are now out of tolerance, and that now has a larger than normal opening between the top cover and that edge of the block facing the head. I did a quick look last night, and didn't see any cracks up there, but, I guess it wouldn't surprise me.

IMG_20180819_211714302.jpgIMG_20180819_211728901.jpg

any thoughts on that one??

again, thanks all!


#8

B

bertsmobile1

thanks ;) I'm not going to put too much more money into it. I got it used year, and the plan was to get something new this upcoming spring. I just need it to last for about another few months of this season and into next.

It is interesting to see that yours held so well. My repair seems fine, but I have a new problem :)

But I am a bog specialist from way back.
Some did need to be redone, that all weep but most people are happy just getting a few more seasons out of the mower , then another, then another.
A couple of litres of oil a season is a lot less than a new engine or mower.
Now I can weld them without warping the cases or making more holes than I can fill.
And of course having gotten the repair down pat none have come in since then.


#9

J

jbeazell

well... nevermind. I just looked closer, and all the front bolts are lose, again. I mean to the point where I could just back them out with my fingers, again, just like last time. My JB weld also now has a big crack through it that follows the general path of the old crack, so that needs to be chiseled off and redone. I'm annoyed that this happened, since I used red locktite on those bolts. In fact, I almost needed to get an extractor for one of the rear bolts as it got stuck in there. I need to get a new bolt since I tore it up getting it out.

I think I'm going to take this thing out back and lite it on fire. Anybody care to donate to the troy bilt bon fire cause?


#10

B

bertsmobile1

Blue locktit is what the factory fits and blue will do.
If you use red you need to heat the cases before you try to remove the bolts.
You may have worn the front threads to the point that they will not hold when hot so either helicoil the 4 front ones or go up to a larger size bolt.
IF you want to make it a NASCAR mower you can always drill the bolt heads and fit lockwire


#11

J

jbeazell

Blue locktit is what the factory fits and blue will do.
If you use red you need to heat the cases before you try to remove the bolts.
You may have worn the front threads to the point that they will not hold when hot so either helicoil the 4 front ones or go up to a larger size bolt.
IF you want to make it a NASCAR mower you can always drill the bolt heads and fit lockwire

I'd love to lock wire it, but I'm not that good at doing those things :)

Any suggestions for keeping those bolts in place.. like SERIOUSLY in place. I'm thinking of the nuclear option like taking the bad boy somewhere to have them all tig welded in place. The bolts I took out were fine (except the ONE). It looked like the red locktite just pooled at the top and didn't sink into the thread bores. Each bolt hole had a perfect little red ring at the top before the threads started. I'm already committed to getting a new one and selling this thing for junk, soon. It couldn't even make it through an hour and a half mow without falling apart and those bolt coming out, again. I'm not going to stop every 30 minutes to tear it down and re-torque those bolts.


#12

B

bertsmobile1

If the top plate is flogged oval where the bolts went through, you might need to replace it.
This was required on a couple .
Some that came i the bolts had been backed out that far for that long the flywheel had ground off the heads.
Did you check with Kohler ?
Other than locktite you might need to fit heli coils or upsize to bigger bolts.

Other than that decide if the mower is worth a replacement engine.

Vibrations are funny things.
One customer had a 2' long crack that they said had been there since new and just weeped a bit.
Others can be fine then split that far in a single mow that the fuel pump no longer worked


#13

J

jbeazell

Other than that decide if the mower is worth a replacement engine.

that's the question of the day. I got it used, and only really wanted it to last a season. It seems to give me issues every other mow. One thing here, one thing there, and most of them are small annoying things, but enough to make me have to split my mowing into two days. I have a post earlier about the drive system not working, and some helpful soul got that sorted for me (thank you to whoever that was!). It's been the plan to replace it this spring, but I don't know if I'll be able to keep it hobbling until then. A replacement motor is tempting to see if I can stretch it out until spring 2020, but I doubt it. I have a feeling that more stupid little things will keep popping up.

I got it cheap, and I expected to do work on it to keep it going. I don't think spending more on an engine than I spent on the entire thing is worth it :) I'm not sure I can trust a Craigslist engine :)

I tried to contact Kolher, but I haven't gotten anything back from them. the engine was assembled in 2007, and I'm not the original buyer.


#14

J

jbeazell

thanks for all the help. I looked a bit closer at the top plate, and sure enough, all the front bolt holes are ovaled. Some have actual impact fractures in the metal around the hole! That must be one hell of a vibration to cause something like that. No wonder those things are walking lose. I doubt there is much I can do at this point. I suspect that anything I do will just end up with the things coming lose again, the gasket becoming useless again, and the crack getting bigger. I could try the helicoil route, but I don't know if that'll do anything either.

On another note, when I grab the crankshaft housing... uh... thing that hangs off the crankshaft (It's not a counter balance because it doesn't move--- it's just a large hunk of metal) , I can move it around inside the block.
SV600-0020_WW_3.gif
I know the top bearing isn't there to help hold it down, but that just doesn't seem right :) Is the bottom bearing (for lack of a better term since there is no bearing) being out of tolerance causing this vibration and breakdown of the engine?


#15

B

bertsmobile1

When the bottom bush area is flogged out it chews the lower seal out very quickly then dumps a lot of oil.
The top plates are a replacement item and it has to be in good condition.

I have looked at these engines and the guess is they were designed for a forged steel crank ( as fitted to the command series ) and then some wit at board level said "No too expensive use a cast one "
THe casting is weaker so has to be bigger there fore heavier and requires a heavier counter weight to smooth things out ,
It is a shame because it was otherwise a very well designed engine


#16

J

jbeazell

thanks for your help on this :)

another totally random question, but how easy is it to fit another engine on there? The chassis looks like it has a bunch of engine mounting holes under the engine. how much do new standalone engines typically go for (southeast US region).


#17

J

jbeazell

Also, I got word from Kohler that they are STILL honoring the warranty for the engine! That's pretty amazing. Only problem is that it is for the original owner, which I'm not :( They asked me to bring the tractor and a copy of my original receipt to an authorized dealer :)

I'm going to head over to the close one to see what they say about things. I have no idea where that will lead, but I'd hate to just toss this thing. The rest of it is pretty OK :)


#18

B

bertsmobile1

thanks for your help on this :)

another totally random question, but how easy is it to fit another engine on there? The chassis looks like it has a bunch of engine mounting holes under the engine. how much do new standalone engines typically go for (southeast US region).

Any new residential Kohler engine will drop right in and plug up.
Older ones might need a bit of electricals if they are fitted with one of the fancy ignitions ( more than 1 small wire on the coils )

Any domestic Briggs will fit as the mower was originally fitted with Briggs as an option but will require a modicum of rewiring, not plug & play.
Kawakasi engines should also go in but you have to watch the size of the PTO shaft, it is a bit harder to work out from the engine numbers if they have 1" or 1.125"
Lots of cheap engines available from surplus stores this time of year as mower making winds down


#19

J

jbeazell

So, I put it all back together, and I locktited AND JB welded the front bolts so that they wouldn't come out. I figured that if this engine was that far gone, I don't care about drilling them out if I need to get back in there. I mowed for about 20 minutes and looked, and the entire front gasket had again puked itself back out the front cover, and it was seeping oil, again. The bolts, however, had not moved. I marked them. They stayed put, but the gasket didn't. So, I kept going until I ran out of gas about an hour later.

That night, I pulled out and cut out as much of the gasket as I could get to. I didn't want to break my hulk hold on those bolts, so I left them there. I put a bunch of JB weld into the crack between the cover and the block where the gasket was. Maybe that wasn't a great idea.

This morning, with fresh gas, I went to finish off about 20 minutes of mowing. I started it up and drove about 60 feet, and CRUNK-a-thunk thunk thunk. It threw a rod and scared the **** out of me. That was seriously loud.

Maybe it was just it's time with as much vibration as was going on. Maybe a hunk of JB weld came off and got into something it shouldn't. I can't imagine that JB weld would actually DO anything that quickly. I would imagine that if anything, it'd get broken down into smaller pieces that MIGHT Impede oil flow somewhere... maybe.. but then it'd have to get through the oil filter?

anyway, this engine is gone. I'll tear it down and take some photos if anybody cares to see the carnage.


#20

B

bertsmobile1

Bummer


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