Busted a bolt on new mower deck.

[Doc]

You might remember this Scag Cheetah is not even one year old. I got it last June.

The mower deck hangs from a chain and is bolted at top and bottom. The bolt going through the chain link on the bottom busted today. No obvious reason as to what caused it to break.

It was held on with a gold bolt. For chaining down the RTV I bought gold chain because it was stronger. Is that the same with bolts?

I bought a stainless steel bolt to replace the broken one. It works but, is it stronger than the gold one that broke?

How do you tell the strength of bolts?

I had my previous Scag Wildcat from 2005 till 2017 and never once did anything other than a belt break.

[Jim Slagle]

Gold should be grade 8, 6 radial lines on head, load 120,000 psi

Grade 2, no radial lines, load 55,000 psi

Grade 5, 3 radial lines, load 85,000 psi

Far as I know most stainless is around or under grade 2

I would put the grade 8 back on. Tractor Supply has a good selection or order on the net from boltdepot.com. They have just about anything you would want and sell small quantities.

Buy a spare,put it in a ziplock, and tywrap it somewhere on the mower so it is easy To find. You’ll never break another!

[Doc]

This gold had 3 radial lines. I will try to match it at tractor supply. Thanks Jim!!!!!

[Jim Slagle]

Originally Posted by Doc

This gold had 3 radial lines. I will try to match it at tractor supply. Thanks Jim!!!!!

3 lines should be grade 5. The grade 8’s I’ve purchased from Tractor Supply are goldish yellow. Either 5 or 8 should be fine for what you are doing.