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B12 rebuild

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Been a while since I have updated anything on here, I got one of my B-12's rebuilt. This is one I bought off of craigslist about 10 years ago. Turned into a lot more work than I had anticipated. Here was one of the tell tale signs that this was going to be a complicated rebuild....


Spring att.jpg

This tractor has been a pain in my butt from day 1. The place I got it from claimed it was a good runner... all of the usual. Apparently whoever had it before me beat the ever loving $*** out of it. Not long after I had it the axel tube split on the transaxle and I had to swap it out. Also it came to me a couple different colors... 

side by1.jpg

side by two.jpg

and definitely not the right seat.... the console in the photo was a different one I had to get for it, since they cut out the right side to put a car battery in it...doner trans came from a big ten, after I got the original one apart decided just to swap it out. As I started breaking it down I ran into all of the sweet mods the previous MacGyver had done to the poor thing(like the spring attached to the cotter pin). The tank had the most inventive rust repair I have found yet. ...

tank 1.jpg

tank 2.jpg

they soldered the crap out of it and then when that didn't work, just puttied it over with bondo!... This was one of the tractors I bought and set aside for a while, didn't really use it much. But when I did it smoked like an old steam locomotive and didn't seem to have the power that a B12 should. Whe I started taking the engine apart I found out why.... When I removed the head this is what I found....


piston 1.jpg

head 1.jpg

It will make sense in a minute.....


piston 2.jpg





Apparently the previous owner lost a 1/4 lock washer....



Found it! Looks like it bounced around for a good while before punching it's way through the piston and created just enough of a seal to keep running.... so the parts list continues! Luckily it did not score the cylinder so that was a bonus.. new piston, new head, new rings, new cam, new points..... 



and time to paint and re-assemble...










rebuilt the pump, new hoses....


I was going to go with an original seat, but since it was a Frankenstein anyway, went with a more comfortable seat. The next B12 will be all original. 


Looks a little better than when I started ;)



Edited by Osgoodtr
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went to PPG for the paint, the original pain code was   115 Yellow 427.2-----201.7 but that was back when they used the Omni base coat. they were able to convert it to the current system they use. Turned out pretty good!


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On ‎2‎/‎8‎/‎2018 at 7:12 AM, acken said:

don't paint the aluminum heads

Very nice restore.  You have been very thorough.  But I agree with acken:  don't paint the head or the cooling fins on the block.  It is probably not a catastrophic event, but I wouldn't do it.

As for the gas tank, you can clean off the bondo and sand blast INSIDE the tank.  If there are gaping holes or rusted out areas you can have them welded up.  Either that or you are back to bondo or JB-weld.  If you only have pin holes, treat inside the tank with POR-15.  

Keep up the beautiful work.

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