[trpshoot]

I apologize for asking a dumb question that is probably been answered 300 times, however, I suck at trying to use this search function.

Anyways, I removed the blades from my 50" mower deck with the air gun, sharpened, and replaced. Well I turned the head off of a bolt that holds the blade in place on an end spindle.

I drilled it and removed it without any issue and bought three new bolts from J.D. this morning.

So what is the torque for the bolt that holds the blade in place? Obviously less than my air gun on high. LOL. I have done this maybe a dozen times over the past 3 years or so. Guess I was weakening the bolts every-time by over-torquing.

Now that I have new bolts, I will break out the torque wrench. HAHA.

 

[dockterj]

From the tech manual for a 318:

Cap Screw (H) . . . . . N·m (54 lb-ft)

 

[KB]

I believe they tighten themselves as they spin. the advice above is probably overkill. I put them on with a 1/4" impact driver that has a max of 100 ft/lbs, and I don't even get close. pretty much as soon as I hear it impacting I stop.

I hope someone else confirms before you try to copy that method

 

[trpshoot]

Well, we shall see what happens. I hand wrenched until snug and then went another 1/2 to 3/4 turn. I have to mow like now. Pretty heavy rain (1-2") predicted for the next 36 hours or so. I hope the blades don't fly off. LOL and seriously at same time...

thanks for the replies.

 

[trpshoot]

by the way, I thought I bought all the manuals for the 318. I have close to a 6" binder. I couldn't find anything to do with the deck. I found plenty of pictures on how to tear the transmission apart. LOL

 

[dockterj]

If you have TM1590 look in section 80-10. It's probably somewhere in the owner's manual for the 318 or the OM for the 50 deck (I don't have either in front of me right now).

 

[knottyrope]

they tighten up on their own when you first start cutting, I just tighten them with my wrench a bit and then cut the grass

they never come off easy and I have to use a cheater bar to get that bolt loose on almost any mower deck I have worked on

 

[gwc]

This is from the 50in mower deck manual. Fasten with washer and cap screw to 50 to 58lb-ft (68 to 79 N-m).

 

[bo2009]

TM 1590 (01MAY95)
Starting 80-10-1, Mower Spindle & Jack Sheave Repair
Torgue Specifications - mower blade cap screws
[at least 5X] , cap screw 73 N.m \54 lb-ft.

OMM 86218 E4 [Operating Manual] 50 Inch, Mid-Mount, Rotary Mower,
for 314, 316, 317, 318, 420, 430 Tractors....

Page 29 [Installing] Blade cap screw torque:
(mower blade) cap screw 68-79 N.m\50-58 lb-ft.

Page 56 [Specifications] Blade cap screw torque:
68-79 N.m \ 50-58 lb-ft.

The TM 1590 is probably the latest\newest manual of the two that I have covering this & it
also refers to the gear box 50" & 60" mid-mount mowers & the rear pto operated grooming mowers.

Manuals distributed by JD. Printed in black & white English. Bobo

 

[hankvc]

I use a Chicago Pneumatic CP734 1/2 inch rattle gun to R&R those blades. When reinstalling, I oil the bolt threads, use the rattle gun to get them close, and torque wrench to finish. It only takes a few rattles to get them close. The C-P pneumatic is capable of something like 200 lb. ft., so you don't want to rattle much after the bolts are seated.

With oiled threads, 50 lb. ft. is plenty. Spindle rotation when mowing is in the tightening direction, so the only risk is having the blades slip in the spindle if they are not tight enough.

 

[trpshoot]

Thanks to everyone for the help. I made it thru mowing the yard without any problems.

 

[jlang]

I had a problem trying to remove a spindle bolt on my 50" deck project this week also. My impact wrench hammered away at the bolt until the bolt head was rounded, so I welded this big nut on the bolt and turned it out with some persuasion and long pipe extensions on my wrench!

Maybe the heat from welding the nut on helped a little.

Nice to have it back together with new bearings in the two outer blade spindles!