12 horse Magnum vs. 10 hp K engine

[johnnymag3 2,520]

Which one is better, and has more PROS than CONS.....and why do you believe your gut....

 

I hate to ask, but i have a situation going on right now that needs to be addressed with your opinions or experiences 

[SPINJIM 1,981]

1.  12hp is better than 10hp, and will handle most tasks, including plowing & snow blowing.

2.  Magnum is better because you don't have to mess with points.  I've had both, and the Magnum was a more dependable start in all weather.

3.  Depends.  How many hours on each, and how well were they maintained?  If both are good, I'd much prefer the Magnum12.

        Jim

[Bill D 1,921]

I vote for the 12 Magnum.  Pros- No points, easy to swap into a tractor that had a K series engine (just add a 5 pin relay in place of the coil), more HP (12HP minimum for a 48" deck). 

Cons, fixed jet carb on some engines.

[johnnymag3 2,520]

I have a 48" deck on a 310-8 I mow with .....seems to be no problem? Its a 10 hp K engine......where does the 5 pin relay go to?

 

[peter lena 8,627]

@johnnymag3, have to go with the magnum 12 , power to easily run what I have , 42" r/d deck , 42" plow , single stage blower . also the electronic ignition , is icing on the cake . all three of my horses are set up the same way , with proven improvements , and regular maintenance. if you detail in the engine grounding , and regularly , add STABIL to all your fuel . my running has been very solid, instant starts , no issues. add rislone zinc to all my oils , easier running is very obvious , as I work on problems , I detail them in , so it becomes a non issue . what ever I  pass on , for advise , I  have been using , so I  know its works , pete    

[Bill D 1,921]

12 hours ago, johnnymag3 said:

I have a 48" deck on a 310-8 I mow with .....seems to be no problem? Its a 10 hp K engine......where does the 5 pin relay go to?

A 5 pin relay is used when swapping a Magnum engine onto a machine that had a K series engine on it.  It takes the place of the coil.  The kill wire for the magneto on the Magnum is wired thru the normally closed contacts of the relay.  When the key is turned on the wire that would normally power the coil on a K series engine energizes the relay and cause the contacts to open, allowing the engine to start and run.  When the key is shut off the relay is de-energized, the contacts close and the magneto is grounded, shutting off the engine.

[pfrederi 17,739]

3 minutes ago, Bill D said:

A 5 pin relay is used when swapping a Magnum engine onto a machine that had a K series engine on it.  It takes the place of the coil.  The kill wire for the magneto on the Magnum is wired thru the normally closed contacts of the relay.  When the key is turned on the wire that would normally power the coil on a K series engine energizes the relay and cause the contacts to open, allowing the engine to start and run.  When the key is shut off the relay is de-energized, the contacts close and the magneto is grounded, shutting off the engine.

Or you could just put in a Magneto ignition switch depending on what model tractor you were putting it on..

Edited July 3, 2021 by pfrederi

[clueless 2,991]

My question is what shape the 12 and 10 are in? Both are great engines, but you question is a realy vague.

[johnnymag3 2,520]

53 minutes ago, clueless said:

My question is what shape the 12 and 10 are in? Both are great engines, but you question is a realy vague.

My question is more of which engine has less chance of mechanically going South. I have had several Magnums with lifter issues, and valve problems....All of the K series engines seem to be long lived...

 

Thats my question I guess, I should have been more clear...I have a 310-8 thats used for mowing larger ares with a 48" deck...no issues. Are the HP ratings actually legit?

 

[pfrederi 17,739]

15 hours ago, johnnymag3 said:

My question is more of which engine has less chance of mechanically going South. I have had several Magnums with lifter issues, and valve problems....All of the K series engines seem to be long lived...

 

Thats my question I guess, I should have been more clear...I have a 310-8 thats used for mowing larger ares with a 48" deck...no issues. Are the HP ratings actually legit?

 

 

 

Interesting since magnums and K series use the exact same valves and tappets....

[johnnymag3 2,520]

Maybe cheaper stuff used in the latter ???

 

[tom2p 2,394]

neither is ideal for a 48" deck or mowing large areas compared to a larger twin - but you already understand this since you have a 418 

both are about as durable as an anvil - but I would lean toward the 12 all other things being equal