Unusual break in Kohler Engine

[WV Sawmiller]

   I mentioned in a different thread yesterday I removed and cleaned out the air filter on my Kohler 25 HP mill motor. When I put the filter back on and finger tightened the wingnut on the stud over the carb the stud broke right where it came out of the assembly. It looked like 1/8" or so and maybe 2-3 threads. I guess the piece could have been drilled out and replaced with a bolt. It looks to be about a 3/32" diameter stud. The little piece/assembly is held on by 2 bolts and was very easy to remove. My local small engine guy took a replacement off an old motor and offered to me but while talking I noticed the stud on his was about 1/2" shorter than mine. The wing nut holds the little metal concave plate down on the filter then a larger plastic cover screws on to it and I am sure the plastic cover would not fit. He showed me a shorter filter that probably would have worked but I like the idea of the extra filter capacity so ordered a replacement which should be here tomorrow.

  What I still don't understand is why it broke as it does not look like that would be a high stress point.

  Has anyone else ever had the stud holding your filter cover on a Kohler engine break like that?

[Southside]

How many crowbars have you broken? Maybe that has something to do with it?  :D

[barbender]

7, in addition to the 3 anvils😁😂

[rusticretreater]

There's no telling with the metal they use these days.  I was messing with a carb on my chainsaw that was sticking a bit and the throttle shaft just broke off.  No defect I could see, just weak metal.

[Don P]

How many crowbars have you broken? Maybe that has something to do with it?  :D

Oh man, just as a public service announcement...don't stand in front of the crowbar! We were working on a floor above a basement, something wasn't going well. I was up on the frame and had a flat bar really cranked. Michelle was on a ladder right in front of me with the nail gun. I was going to honk on the bar while she shot. The flat bar broke and there was her face, yup, right between the eyes. The electrician was there working on the entrance, I let him know and we hauled boogie down the mountain. There was a domestic and cops in the ER when I walk in with a bloody wife "Lucy, you got some 'splainin to do!" "No, really, I didn't mean to hit her in the face with a crowbar". It was about dark when we got back to the local store for gas, we hadn't been on that site more than a week but they had already heard, asked how she was and I'm sure relayed the news. Gotta love small towns. Anyway, can't help on the bolt, I've broken a few hammers and have never owned an anvil :D.

[moodnacreek]

Fortunately I have never had a crow bar break but band saw bands do break at the weld from time to time and when they are new. I suppose the annealing process on the weld is at fault.

[WV Sawmiller]

   The point where this stud broke does not appear to be anywhere near a weld. It looks like they made a wide U shape, drilled a hole in the middle and pressed the stud in from below. It has a wide, thin, round head but no way to screw it on.

  My mechanic said he has never seen one break there. I have 1193 hours on the mill/engine. He did say he has had the bolts holding the piece on vibrate free and fall into the carb damaging the motor.

  I am not a metal worker and have never knowingly damaged an anvil. I think it was in in a FoxFire series book on gun making and metal work but it could have been on TV or the internet that you never strike an anvil face directly with a hammer. You always need to have a piece of metal between the hammer and the anvil face. My tool sales friend at our local flea market may have advised me of this but since I don't ever plan to buy or use one it is a moot point.

  For the record I have never broken a crowbar (Except for maybe the little split nail puller part) although I may have bent a few.

[kantuckid]

Going from memory, my Kohler Command pro 15hp has a larger diameter screw holding likely that same circular air filter? It's 1/4" in my mind but certainly not 1/8" dia..
Why not drill out the part that has the stud to next size then taking a same sized cap screw, saw off the head and make a new stud.  
The main tool safety no/no is to never, ever strike a hammer face against another hammer face. Bearing steel is also very brittle and can easily blind you when struck. Brass drifts are often used. Anvils not so much. 
My main crowbar is softer than a hammer face and has been beaten into a wood joint many times, thus the head curve shows some peening. Fairly hard to break one?  :D 

[WV Sawmiller]

Kantuckid,

  That would be an option if a new piece cannot be obtained but the little piece is only about 3" long X 3/4" wide, U shaped with the stud coming out of the middle. There is about a 3/4" bold on each holding it on. There is a loop from each side the fuel line slips through. It is very simple to replace and, I hope, not too expensive to buy. I should find out later today on the cost.

[WV Sawmiller]

 

Here is the new/replacement and the broken part. The wingnut and rubber bushing goes on the stud under and over the concave metal plate over the filter. The plastic cover tightens down on to the same stud.

Here you can see the 2 mounting holes on each side where the bracket is mounted over the carb. It looks like the broken piece of the stud could be punched out and a new bolt placed on and it would work fine. I don't know how the stud is attached to the bracket as the round head does not accommodate a wrench or such. I do know you don't want to risk small loose or broken metal parts falling down into the open carb.

EDIT: BTW - cost was $11 for part, $15 for shipping.

[doc henderson]

looks like it could or would be tack welded...incase you break the new one! :D :D :D

[WV Sawmiller]

   I probably could but since I don't weld either, a new part probably costs more than a decent repair job.

   Hopefully, and since nobody else has responded with similar report of problems, this is a one-off occurrence and the last time I will see it. It is certainly a much easier fix than most things that happen to me. 

[ladylake]

 At least it didn't suck it through the engine!   Like Doc said it might be good to weld or braze it better.  Steve

[WV Sawmiller]

LL,

  Yeah but when it occurred the engine was off and I was just doing some PM cleaning the prefilter and knocking much of the dust out of the filter and putting everything back in place. I even had the choke shut in case I did drop some dust or something which was handy as today when I put the new part on I found several ounces of water pooled there that had leaked through holes in the cover and the loose cover. I was able to remove it before starting and the engine started and ran fine and all is right with the world again.

[trapper]

Speaking of hammers I have a piece of steel between my thumb and finger for years from using a sledge hammer to drive steel wedges splitting wood.  couple pieces broke off of the hammer  and when the piece went into my hand I sawed the handle off it to not be tempted to use it again

[kantuckid]

Here is the new/replacement and the broken part. The wingnut and rubber bushing goes on the stud under and over the concave metal plate over the filter. The plastic cover tightens down on to the same stud.

Here you can see the 2 mounting holes on each side where the bracket is mounted over the carb. It looks like the broken piece of the stud could be punched out and a new bolt placed on and it would work fine. I don't know how the stud is attached to the bracket as the round head does not accommodate a wrench or such. I do know you don't want to risk small loose or broken metal parts falling down into the open carb.

EDIT: BTW - cost was $11 for part, $15 for shipping.

A stop nut would hold it from losing something into the engine. Thats a different design than my CH15 air filter holder. I'd change the screw sizes and use a stop nut then get a wing nut that fits the new size involved before I'd buy a part. I assume you air filters got a circular steel disc with a hole in the center which is easily modified as well. No real need to weld or braze anything. 

[kantuckid]

Speaking of hammers I have a piece of steel between my thumb and finger for years from using a sledge hammer to drive steel wedges splitting wood.  couple pieces broke off of the hammer  and when the piece went into my hand I sawed the handle off it to not be tempted to use it again

I used splitting wedges a lot in years past. Like many folks I mostly never wore safety glasses when splitting wood.  I did take them into my tech school welding program to have the peened heads cleaned off periodically as they roll over and become more dangerous. Wedges are softer steel than the sledge but do roll over whereas a hardened hammer face sends a chip more easily no matter how long it's been used. 

[doc henderson]

I sewed up the lip of a kid using a Pirahna metal muncher.  he had a chromed die in it that fractured and he was hit in the lip with the flying chunk.  he came in a week later to get the stitches our.  he then asked what do you think this lump in my cheek is from.  1 x-ray later and there was the chunk that traveled along planes in the tissue and stopped in the cheek.  a little cut and a few more stitches.  makes you wonder if he was telling secrets...

it looks like there is enough room (on the backside) for a bolt and nut (front) to put the old one back together.  

[WV Sawmiller]

   The new one is installed, the old one is in the trash so that is a moot point. I don't know how they install the stud in the bracket. The head is perfectly round so not designed to hold. I assume it is welded in some fashion. 

   The shipping costs much more than the part itself but combined it is still cheaper to replace than repair when you consider time, skills and equipment I don't have anyway. I was speculating on repair only if a new part was not readily available. I wouldn't keep the repaired piece as a spare as if this one lasts as long as the last one (7 years) I'd never find it when the next one broke anyway. :D

    As I mentioned nobody else has chimed in with similar problems so it is entirely possible this was a freak occurrence and I may never break another one. 

[doc henderson]

I agree.   8)

[Don P]

After replacing the carb on a briggs on the Lucas from some micro piece of trash I could not clear I began wondering, why aren't we using the old oil bath tractor style filters. 

[doc henderson]

they would actually require some maintenance.  
they are so good, things would last for decades again, as well.

[Chad8324]

 began wondering, why aren't we using the old oil bath tractor style filters. 
I recently bought Woodland Mills HM126. The pars manual for the engine shows an oil bath air cleaner available.  I was unable to find one anywhere my Google full took me. 14 HP Kohler CH440. 

[hamish]

I have seen that stud break many times, normally on Kohler powered standby generators.  Not a big deal unless the stud gets sucked into the intake.  Easiest fix is to drill the mount and use a bolt with a locknut to secure it to the mount, then re-assemble and use the normal wing nut on the air cleaner.

[WV Sawmiller]

   I wonder why it breaks on Gensets? Do you think it breaks more there than in other applications? I have a Generac standby Genset with a Kohler engine with this same design on the filter. Now you have me concerned. :