Blades Rightie tightie leftie loosie or?

D

DjDrew

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• Jul 9, 2017 / Rightie tightie leftie loosie or?

• #1

Simple I am sure but I could not find a reference anywhere.

To replace the blades on a 1987 MTD riding mower 36" deck, are they left or right hand threads?
This has a 9/16" head center bolt on each blade, with double 1/2" head outside bolts, 2 each on each blade.
I am not sure at all whether they are all left hand or right hand bolts or varied.

Anyone got a quick answer please. thank you in advance.

 

B

bertsmobile1

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• Jul 9, 2017 / Rightie tightie leftie loosie or?

• #2

All bolts are right hand unless other wise stated.
the only time you will find a left hand thread is on a left hand cut blade as you have with some rear discharge decks.
Left hand bolts are always marked so they can be identified although on a deck bolt there might not be much of the head left.

 

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ILENGINE

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• Jul 10, 2017 / Rightie tightie leftie loosie or?

• #3

If the blade discharges grass to the right then you have right hand thread. If it discharges to the left then you have left hand thread. My Rhino finish mower for my tractor is left hand thread with a left hand discharge. Some Simplicity and older Allis Chalmers lawn mowers where left hand discharge. I have a customer with a Kubota that has one of each The left blade is left hand and the right is right hand. the blades counter rotate from each other.

 

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DjDrew

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• Jul 10, 2017 / Rightie tightie leftie loosie or?

• #4

Thanks everybody, especially for the quick reply. I am having severe problems taking these bolts out unfortunately, as it looks to have been ages since they were removed. Heads are dog-earing and I am afraid for the worse on this. I have let them soak overnight after spraying with WD40 and used a penetrating spray also to no avail.

 

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bertsmobile1

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• Jul 10, 2017 / Rightie tightie leftie loosie or?

• #5

They tighten up with use.
5 or so times a year I have to get the angle grinder out and knock head off
once the head if off they generally just undo with fingers as the blades are slightly sprung on most mowers and the bolts rarely ever corrode inside.
And if it makes you feel any better I use a 1900 ft lbs impact and there are times it just won't shift them.