How do you adjust the blade control cable on an MTD pro?

Sounds as if the valves need adjusting... You will need a feeler gauge and find out what the specs are for that engines valves clearance...

It sounds like the auger always turning is the auger engagement handle/line/connections are not adjusted correctly. They/it is too tight causing the auger to engage before it should. It may be up at the handle where you loosen a jam nut, screw in or out a threaded shaft, and retighten the jam nut. (If you have ever adjusted a bicycle brake it is similar.) (I have a craftsman, made by MTD, and I think I saw MTD also list Ariens.) Or it could be an adjustment somewhere else (but I'm not sure where).

As far as one auger moving and the other not, you may have a shear-pin (shear bolt as the manual calls them) on each side of the auger's shaft (my craftsman has one on each side), and the one on the side that stops turning is sheared off. (It moves without snow present due to the driveshaft inside the outer auger shaft turning, but it won't turn under load (snow).) You may confirm a sheared-pin by turning the machine off and try to turn the auger blade. If it turns somewhat easily, that's a bad shear pin. Remove the old shear pin. If the old one is as long as the new one, that aint the problem. The shear pin in the image is one kind. Mine appear as a straight bolt (no grooves), threaded the entire length. You will have to rotate the auger blade until it aligns with the hole in the shaft. Use a nail that fits and rotate the blade until the nail goes in. Remove the nail and screw in the shear bolt:


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The auger clutch control up at the handle looks like this:
From my manual
Auger Control

• To check the adjustment of the auger control, push forward the left hand clutch grip until the rubber bumper is compressed. There should be slack in the clutch cable.
• Release the clutch grip. The cable should be straight. Make certain you can depress the auger control grip against the left handle completely.
• If adjustment is necessary, loosen the hex jam nut and thread the cable in (for less slack) or out (for more slack). Recheck adjustment. Tighten the jam nut when correct adjustment is reached.

Here's another view of that:

I hope the above info helps you take care of both issues.

Assuming you have put the blade drive lever into 'disengage' check the blade drive belt tension. With blade disengaged, belt should have significant slack. You may need to adjust the control cable, adjustment is usually on the mower deck; or you may have some debris on the deck preventing the pully to release belt tension

Hello
Go under the mower and install a cable shorting clamp like you use for car park brake cables that are stretched, which is most likely your problem. You can buy this type of small "U" bolt clamp from any hardware store.

the only way to fix it is fit the right blades
they have fitted the wrong blade's to it,,,
the blades should overlap when cutting the grass they cannot crash into each other as there are (timed up) not to do that the new blades they fitted are to short so you have no over lap on the gutters that leaves a strip of grass left uncut between the blades,,
call them out to put this stupid mistake right,,,

The cable connects to the pin on the deck brake assembly and the other end connects to the pin that hangs downward from the upper idler assemble. Each end is held in place with a washer and cotter pin.

You need to check the owners manual. And be sure you have the correct belt.

You can download a manual here:
http://manuals.mtdproducts.com/mtd/public/list.jsp

try this link it may helphttp://manuals.mtdproducts.com/mtd/public/list.jsp?BrandCode=10451

my chipper had problem with wiring issue that the battery isn't able to take up the electricity supplied to it.. u know, the conductor between them..
if possible get a manual from reliable-store to fix it urself thats I did