312-8

[Margie 17]

I just bought a 312-8 today! Already love it although I haven’t mowed yet. What is the best spark plug I can use (Champion RH-10C?) and the best transmission belt? I don’t mind spending a bit to get the best quality. Thanks in advance! 

[ineedanother 2,648]

Excellent! We'll need pictures. We love pictures. The RH-10 is the correct plug and you can cross reference easily to other manufacturers. You'll have questions, everyone does but I have a 312-8 and it could very well be my favorite. Great machine! Here is a recent thread similar to what you'll be asking. 

 

[leabassett@sbcglobal.net 174]

My 312-8 is a monster in the snow.

[gwest_ca-(File Mod) 12,384]

4 hours ago, Margie said:

I just bought a 312-8 today! Already love it although I haven’t mowed yet. What is the best spark plug I can use (Champion RH-10C?) and the best transmission belt? I don’t mind spending a bit to get the best quality. Thanks in advance! 

Have a model number and serial number off the rear seat pan? Will link you to the appropriate manuals.

[953 nut 67,631]

The TORO / Wheel Horse number for your 312-8 drive belt is 7473 which is a 82" X 5/8" V Belt. Many of us have used the Tractor Supply Kevlar belts with good results. Bew very cautious about buying belts on  that are listed with TORO numbers, many of them are not the correct width and will not work.

https://www.tractorsupply.com/tsc/product/huskee-v-belt-5-8-in-x-82-in-oc-4461826?

[clueless 3,430]

49 minutes ago, 953 nut said:

The TORO / Wheel Horse number for your 312-8 drive belt is 7473 which is a 82" X 5/8" V Belt. Many of us have used the Tractor Supply Kevlar belts with good results. Bew very cautious about buying belts on  that are listed with TORO numbers, many of them are not the correct width and will not work.

https://www.tractorsupply.com/tsc/product/huskee-v-belt-5-8-in-x-82-in-oc-4461826?

If you can find one, their still out there, some members here sell them stay with an original Wheel Horse (Toro belts) their aren't cheap but there is a good chance the belts on your 35+ year old 312 are the original ones. Your drive belt (to the transmission) original belt number is 78-7100 it was later replaced by Toro 7473, it is 5/8" x81.9 anything you buy now are 5/8"x 82" does that 0.1" make a difference obviously it did the engineers who designed this things. The TSC huskee belt would be my aftermarket choice, they are about half the price of an original, so you can change it once and still come out ahead. Sorry, didn't mean to ramble on but I took my meds early today and I'm on my 3rd cup of coffee .

[peter lena 9,971]

@Margie  agree with @953 nut  on the T/S aramid belts , been bombproof for me , remember , what eats up a belt ?  related , pulley in the set up , is incrementally hanging up / stopping , due to lubrication failure . while you are  changing out the belt , take the time to  feel / spin every related pulley / if possible , that will  show the start  / reason for noise / wear . thats your que , pete

[Lee1977 7,719]

I use Autolite 216 in my 12 HP Kohler engines  The reason the on line belts don't work is the material on back side of the belt is not seal down.

The Wheel Horse drive has a bracket on the clutch idler bracket that clamps the belt to stop it when the clutch is pushrd in.  Deck belts need the 

seal down back side because the run on flat idlers on the back side.

[Margie 17]

10 minutes ago, Lee1977 said:

I use Autolite 216 in my 12 HP Kohler engines  The reason the on line belts don't work is the material on back side of the belt is not seal down.

The Wheel Horse drive has a bracket on the clutch idler bracket that clamps the belt to stop it when the clutch is pushrd in.  Deck belts need the 

seal down back side because the run on flat idlers on the back side.

Awesome!! Thank you!! 

[sqrlgtr 3,393]

A little late to the party but, I like the NGK B6L plug myself a close second is the Autolite 216. Hard to beat the tsc belts never had any trouble with them.

Edited 1 hour ago by sqrlgtr