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

 

[aussietrev]

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

Final update. Pulled the twin out and removed the sump. The conrod remains were in about ten pieces. Went with the 18HP from Dave in Charmhaven. After tapping the mounting holes it bolted right in as luckily the chassis is double drilled for the V twin or a single B&S/Honda pattern. The plug on the engine was the same so the wiring was simple, the throttle cable being longer for the twin barrel carby had to be run in an S pattern but it works fine now. There seems to be very little difference in the cutting performance although it does seem to be a little slower across the ground when travelling from area to area. With the side exhaust it is a lot louder than the twin was. Thanks for your help and advice, much appreciated.