Yanmar 186 crack in cast iron housing

[Yanmar186d]

Hi all, well I've been doing a bit of work on my tractor fully rebuilt the back hoe , new pins bushes cylinders welding cracks sandblast and 2k paint, new bucket on the loader, rebuilt front diff, rebuilt starter,new ignition switch, rebuilt steering box with new shaft,had the radiator rebuilt with new hoses etc, changed all oils new front tyres and a good pressure wash, as I was fitting the cover that sits over the power shift linkages I noticed a nice crack in the housing about 8 inches long, this is the housing that bolts to the engine and the transmission so it's the centre section of the tractor frame. Is it common for this to crack? I know it's due to the tractor having a hoe and loader fitted but has this happened to any one else? I'm a boilermaker by trade but I'm not keen on welding it as I can't see it lasting so I will try and find a new section. Has anyone had something like this welded with no problems?

 

[clemsonfor]

I would think it is craked from the abuse or just use with the hoe and loader. That is a lot of extra strain on that little tractor. It cracked due to a weak point unless you can get a stonger than original material out of the weld i think it would just recrack. ( i have heard cast is hard to weld and usually will recrack...also heard of blocks welded up but they dont have the same strain on them most of those are freeze cracks.)

I would try and find another section. thats a bummer though

 

[kenmac]

You should be able to weld it. Drill a hole at the beginning and the end of the crack. You'll need to heat it some. Drilling the holes should stop the crack..If it were mine I'd weld it.. I was a welder in my previous life... Have welded cast many times..Probably use a nickle rod, but I have used 6010, 6011, etc,.

 

[Soundguy]

if there is no subframe, then 3pt hoe's are hard on castings. heck.. they are hard on castings WITH subframes.

 

[Soundguy]

there are some pretty good CI rods out there. I'd likely try a weld too, and then fab a subframe.

The last cast rods I got, I did a practice test on an old manifold I had that had the face of the last port, and the mount ear pitted and burned out from a gasket failure. I ground it flat and 1/8" under depth, heated with a propane torch and built up in single passes with peening, then flush grinding for another pass... then slow cool .

end result.. no cracks.. no warp.. true fit. the deposited metal filed and ground out JUST like cast ion. I was impressed.

previous to this I've used 6013 to repair cast brackets with great results too.

 

[kenmac]

Forgot to add.. You need to V out the crack with a grinder, make sure all is as clen as you can get it ,B- 4 U attempt to weld

 

[normde2001]

Hi all, well I've been doing a bit of work on my tractor fully rebuilt the back hoe , new pins bushes cylinders welding cracks sandblast and 2k paint, new bucket on the loader, rebuilt front diff, rebuilt starter,new ignition switch, rebuilt steering box with new shaft,had the radiator rebuilt with new hoses etc, changed all oils new front tyres and a good pressure wash, as I was fitting the cover that sits over the power shift linkages I noticed a nice crack in the housing about 8 inches long, this is the housing that bolts to the engine and the transmission so it's the centre section of the tractor frame. Is it common for this to crack? I know it's due to the tractor having a hoe and loader fitted but has this happened to any one else? I'm a boilermaker by trade but I'm not keen on welding it as I can't see it lasting so I will try and find a new section. Has anyone had something like this welded with no problems?

That's the bell housing that has been reported to break entirely in half several times over the years on small tractors, if no subframe. You might be better off to try to find a bell housing , and replace with a subframe.

 

[Yanmar186d]

Hi, i found a Second hand bell housing so ill change it over and ill repair my cracked one and keep it spare, the backhoe is mounted to the rear of the tractor with a sub frame, when I had the rear out riggers down and the loader bucket down with the tractor in the air the crack opens up a hair line, when I have the new housing fitted I won't be jacking the whole tractor up of the ground using the hoe as I think this would be the cause of the housing to crack. Cheers Daniel

 

[normde2001]

A correct sub-frame connects the front and rear of the tractor, in addition to the bellhousing.

 

[clemsonfor]

Hi, i found a Second hand bell housing so ill change it over and ill repair my cracked one and keep it spare, the backhoe is mounted to the rear of the tractor with a sub frame, when I had the rear out riggers down and the loader bucket down with the tractor in the air the crack opens up a hair line, when I have the new housing fitted I won't be jacking the whole tractor up of the ground using the hoe as I think this would be the cause of the housing to crack. Cheers Daniel

that seems like a good idea. Not just 3 points of contact but 7 or 5 depending upon if you lift the front wheels with bucket or not. The outriggers are just for stability anyway. I am sure this new process will distribute stress way better.