I got the replacement engine buttoned up and running, on the 129. So far, it's a smoker. Started right up easier than that tractor ever has, I put brand new points, condenser on it, (OEM Kohler) along with the carb from the original motor/ plus went thru and checked the valve clearance, put new gaskets on the breather, etc.... I had bushed that carb and rebuilt it, a couple of years ago. the one that came with the "new" motor, was all kinds of sloppy.
I had done all of that to the old motor, back when I got that machine a few years ago, as well..... the wire pulled out of the condenser body way too easy, I don't know how it ran like that at all..... that condenser wasn't that old, either.
The "new" motor starts too easy, and runs too good, to be a dud. I let it run about an hour, and idled it down, revved it up, several times/ after about the 1st 1/2 hour I put some Marvel and some Seafoam in the gas tank and let it sit and run about another 1/2 hour.... smokes out the exhaust not the breather. gray/black, not blue... but the carb adjusted in real easy, I did get this motor quite cheaply....I had high hopes for it, being the shroud has 2 stickers on it, one saying the engine was "rebuilt" by replacing the short block... it's "replacement Kohler engine" gray. they must have run the snot out of this one too, it seems. the 127 it came from, is older than my 129, after all. Worth what I paid, even if it is a core..... the narrow base Cub versions seem to switch to "unobtanium" when I need one. Plentiful when I don't. hopefully when I run the seafoam and Marvel out of it, and put "straight" gas in it and "work" it, the rest of the smoke goes away. Hopefully. Especially as how it isn't that badly carboned up, either......
It's got a cast iron pan, and someone on Ebay right now wants more for just a narrow block cast iron pan, than I paid for this whole motor.
When I originally got this replacement engine going, sitting on a moving dolly, it smoked a ton/ but I thought that was just because of how I had to feed it.... out of an aerosol can of Gumout..... and then a Windex bottle full of gas sprayed into the carb..... I didn't run it long that way, when I 1st got it.
but now, with a known good carb on it/ and taking gas from its tank as intended/ it still does it..... seemed like it might be letting up, the longer it ran though..... fingers crossed. At least it ain't bubbling out at the head-block seam.... and up the head bolt shanks, like the old motor did (and I put a head gasket on that old motor, less than 15 operating hours ago) It smoked badly too..... more, when the governor would kick in and I got into a heavy patch than all the time/ like this engine seems to want to do...... I haven't mowed with the 129 with this engine, yet. hopefully this other engine runs good enough, long enough for me to do an overhaul on the old one, allowing for the time I know it will languish in machine shop jail..... the shop that's done the last couple for me does great work, but are always backed up and don't get in a hurry for this small stuff.