Help, get this motor running
 

Got a cub 123 from the junk yard. It's missing the starter generator and looks like there was some problems with it. I put on a good starter generator on it and the voltage regulator was making a weird noise. So then hooked up the coil to the positive and jumped the starter. It would spin a little faster. I'm only getting 30psi on a compression gauge. Time for rebuild???

Is it an acr motor? Automatic compression release? Sometimes compression can be a hard read on these things

It's a k301as that's all I know.

The ACR will give a false reading on actual compression. It makes the engine easier to start with the starter generator.

If you remove the cam cover and unhook the acr springs you can get an idea of the compression, but not a great one. A cylinder leak down test is better. I would say it was in a junkyard for a reason. I would try to get it running and go from there. Least pull the head . I'd say she gonna need a rebuild.

you have to spin it backwards to get compression readings or at least from what ive heard , got any pictures

How good are the points and spark plug and are they clean? Is the coil and the condenser a good one? Is it timed correctly? Is it getting fuel to the carb and is the carb ok? If you have 35 psi compression on an K301 ASR it should at least sputter :biggrin2:. If you have spark, fuel and correct timing, it should start!!

Everything is unknown. The glass bowl is missing so I can't get fuel to it. I wanted to make sure the motor had compression. One thing that is weird I can push the tractor. Like there is no compression or the transmission is blown. How to I check the coil and the points?

being able to push the tractor is not abnormal especially if it hasn't run for awhile or if the trans disengage is engaged or stuck. Hydro's won't try to turn the motor when rolling like a gear drive.

If the cover is on the points, remove it and first just visually look at them. If they are all crusty white and corroded at minimum they will need a good clean up with emery cloth or a points file. then check the gap. You can then crank it to see if you have fire between the points contacts, if so you are good there, if not make sure you have power to the points, if yes replace the points.

As much as needs done to this machine, I'd suggest starting here..... K Series Service Manual


Since you got it out of the scrap yard, I'd pull the head before I went too far. Drain the oil and see what's in it too.