Beware Cheap "Grade 8" bolts

S

spadra

Well-known member
Decided to replace the head bolts with supposed "Grade 8" bolts bought by the pound from my local co-op. Four of them broke (two short, two long) bringing them up from 40 to 45 foot pounds. Luckily, all of them stayed in one piece and I was able to back them out. Cleaned up the originals and they all torqued nicely.

Cheap Chinese :censored:. I won't make that mistake again.
 
Wow. They broke but stayed in one piece , I cant picture what you are describing. I am fortunate enough to have a Fastenal store nearby that has almost everything i need in stock , or next day or 2. :D :D :D Good luck with your project.

Jim
 
This post is an excellent opportunity to bring up a much related subject: Stainless steel bolts.

I know that a lot of us would like to use SS instead of "normal" bolts.
However, keep in mind that in most cases SS bolts are softer and therefore more likely to break.
As far as I know, there are no grades of SS bolts to correspond to the bolts we are used to.
No grade 5 (3 marks on bolt head) and no grade 8 (5 marks on the bolt heads.)

Some of the imported SS bolts seem to have only the heads dipped. I have some that have rusted.

Boutwell's $.02 worth.
 
I have had some breaking problems with the( home Depot etc.) SS screws and bolts also as many may have. I usually buy the "important " bolts that carry a load from a trusted source like fastenal or Grainger and havent had any problems with them. :D :D
 
Gary is right. SS should only be used for cosmetic purposes. The heads will snap off when torqued very hard. I don't know the answer to "cheap" grade 5 or 8 bolts. All bolts may be made in China now. I changed out the rusting plated screws in my horse trailer to Fastenal SS screws and had a lot of the heads snap while driving them.
 
I usually tighten a bolt with a 24" sears breaker bar. One squeak for 5/16 and two squeaks for a 3/8 bolt. :) :) :)
 
I am replacing the head bolts on my Cub after breaking one of the originals off in the block and have no idea what to replace them with, is grade 8 hard enough?
 
Grade 8 is proper for the head bolts. They can be broken but shouldnt have a problem if properly torqued . Dont forget the thread sealant as the hole is open to the water jacket. Using the thread sealer will require less torque than the 45 ft lb but others will have to specify that torque value. I cant remember right now. CRS must be.

jim :D :D :D :D
 
While SS bolts and nuts seem glamourous and shiny, they are not the best choice for most Cub applications. The metal does not take vibrations and shocks well at all. The cheap varieties are bad to gall when bolts and nuts are used together. Until you get one galled and try to get it apart you haven't lived.
 
This Thread should read

Beware Cheap Bolts

If they were truley grade 8 then they would not have broken under that little of torque

Just know your supplier so you get good bolts.

By the way they are required to tell you the country of origin upon request

Mark
 
I have used plenty of stainless up to this point on my 57 cub except for locations where a grade 5 was obviously required. As for head bolts, used the originals!!!!
 
As far as I can tell everything was done right: Bolts slathered with anti-sieze, torqued with a reasonably calibrated torque wrench, etc. My best guess now is that those "Grade 8" bolts weren't. I don't recall where I read it now (maybe here), but apparently there is quite the trade in counterfeit bolts. That is, bolts that are marked as Grade 5 or Grade 8 but aren't.

Does anyone know of a domestic producer (not just distributor) of bolts?
 
Grade 8 bolts may work for head bolts but they are not the proper ones.

Quote from Engineering Drawing by Thomas E French.

Bolts for high pressure pipe flanges, cylinder-head studs and similar fastenings against pressure, require that an initial tension be set up in the fastening by elastic deformation of the fastening, and require that the component be held together so that the joint will not open when the steam or other pressure is applied.

This has been discussed in the past and the thrust of the conversation was that cub cylinder head bolts by Case IH is the proper way to go, with new bolts each time because of the stretch. If I remember right there is a difference in length in some of the bolts in a Case IH set.

All that said it is your cub, so do what you want. Short cuts are just that. Some times they work and some times they don't. Some times they seem to work, but later well that is something else.

Re reading this , Lord I am getting old and crotchetty.
 
beaconlight":2cxhhwdc said:
Grade 8 bolts may work for head bolts but they are not the proper ones.
Lord I am getting old and crotchetty.
Click to expand...

Bill,

You may be "getting old and crotchetty."
But you are dead on right!!!
 
I hate to be a pain but I don't understand why a good grade 8 bolt form NAPA would not be suitable and also what kind of sealer do you use on the bolts? I want to do mine right the first time because I hate to do things twice.
 
Beerhunter : If you search prior posts you may finds threads discussing this. Quality Grade 8 seems to be the bolt of choice as an alternative to the very expensive head bolts offered . Grade 8 may not be the "proper" bolt but they are a frequently used alternative, even by me , with success. :D :D :D :D

As stated in an earlier response , a cheap quality grade 8 that breaks easily is not truly a grade 8. Make sure to find a good quality bolt. :D :D
 
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