D125 Coil problem?

[aussietrev]

It is barely running, will start eventually but rough as. If it did break a conrod, depending where it broke, e.g., close to the big end bearing, it would be possible to still run if the piston was up at TDC I guess. I guess there wouldn't be that much of a problem of power down size for a new 18HP against a tired 20HP. Plenty of 42 inch cuts run similar engine sizes.

 

[Tiger Small Engine]

Tiger if you had bother to look-up the D125 you would had seen the JD used a V-twin on the mower. I have had v-twin even with a fuel pump still run somewhat with a hole in the crankcase.

https://partscatalog.deere.com/jdrc/sidebyside/equipment/68105/referrer/navigation/pgId/1100914

I am pretty familiar with John Deere riding and zero turn mowers. Whether the D125 is a 2 cylinder or not, with a hole in the crankcase, we call that a clue that things ain’t good. Maybe a little less pointing fingers and a little more teamwork would be in order.

 

[aussietrev]

So you think that a broken rod might be the problem? Lucky for it to be even to running at all.

Took out the plugs and run a compression test, 120PSI on one, Zero on the other. Using a very bright torch peered through the hole in the crankcase, there is only one con rod attached to the crankshaft, just a shiny spot above it where the other one should be. So I guess either the big end bolts weren't done up properly or it snapped them and threw something through the case.

 

[bertsmobile1]

Well Trev it is dead so you have to make up your mind if it is worth putting a new engine in it
A new B & S will set you back around $ 2,000 ( Aus ) a Kawasaki around $ 1,500 for Kohler you will need to auction of one of your children
A Loncin will be a little under $ 1,000
A B & S short block is not a viable option in Aust as B & S are unlikely to have one & if they do it will cost near the same as a new engine
As for engines, anything with a 1" PTO will go in but you will have to do some wiring modifications
In NSW , Dave in Charmhaven & Johnno & Johnno both direct import Loncins and their retail is only 10% above my wholesale .
Unless you are bagging +/- 4 Hp will make no difference apart from the bigger engines using more fuel