High Tensile bolts.

kevin powles · #1 25-08-09, 09:24

Hi, On the front of a Canadian Carrier there are some counter sunk bolts which hold the front plate on 3/8" BSF. I would of thought the ones which go through the lifting eyes would of been high tensile.

I cant find any here in the UK, they do counter sunk bolts/set screws in high tensile but they all seem to be allen key counter sunk heads. As the ones in the lifting eyes form part of a lifting device, I need high tensile with a minimum rating. Has any one else faced this problem.

Cheers Kevin.

Oh, I do plan to lift my carrier on and off transport fully loaded with kit.

Ron Pier · #2 25-08-09, 11:24

Kevin, I haven't tried to locate those bolts, but I had a similar dilemma with some motorcycle front guard mushroom head bolts. I could only find Phillips heads, in the correct shape and size. I bought them and took them to my local friendly engineer. He tig welded the cross and then milled a nice screwdriver slot. If all else fails you could do that with socket head screws. Or send them to me and I'll get them done.

Ron

Lynn Eades · #3 25-08-09, 12:05

Firstly, the bolts holding the tow/lift eyes, are 7/16 BSF. I dont think they are high tensile, but it make sense that they would be at least at the low end of medium tensile, as apposed to mild steel.
Any allen headed screws you find will be high tensile.
I need some of those screws,as well, and I know somebody who has bags of them (original carrier parts), and he will probably never use any of them.
Cheers.

kevin powles · #4 25-08-09, 13:51

hi, thanks for the info, lynn who's got some then?, do tell.

kevin.

kevin powles · #5 25-08-09, 13:58

hi lynn, are you saying the ones which go through the lifting eyes are 7/16" bsf, the rest of the front plate is 3/8" bsf ???.

I didnt notice before, if so I have about 10 7/16" bsf bolts which came from Brian Asbury, i always wondered were they went, what a numty.
kevin.

Phil Waterman · #6 25-08-09, 14:40

Try this out fit http://www.fastenal.com/web/home.ex they are a commercial outfit that I've had good luck with. They seem to have a pretty good international distribution system, though I don't see listed an outlet in Australia or New Zealand.

The only problem is generally they only sell in bulk qunatities of 50 or 100 but their prices on grade 8 bolts is low enough that your buying a box of 100 for what you pay in the hardware store for 25.

One heavy equipment dealer near me has put is bolt bins out front in the parts area and sells Fastenal Grade 8 bolts by the pound. (about $4.50USD) I go in and buy bolts, nuts, flat washers, and lock washer taking a hand full or two of each size I need to restock my bolt drawers. I worked out the cost and it comes out that I'm using all grade 8 bolts for lot less than what cheap (quality) grade 5 hardware store bolts cost.

Cheers

Alex Blair (RIP) · #7 25-08-09, 16:17

Quote:

Originally Posted by Phil Waterman

Try this out fit http://www.fastenal.com/web/home.ex they are a commercial outfit that I've had good luck with. They seem to have a pretty good international distribution system, though I don't see listed an outlet in Australia or New Zealand.

The only problem is generally they only sell in bulk qunatities of 50 or 100 but their prices on grade 8 bolts is low enough that your buying a box of 100 for what you pay in the hardware store for 25.

One heavy equipment dealer near me has put is bolt bins out front in the parts area and sells Fastenal Grade 8 bolts by the pound. (about $4.50USD) I go in and buy bolts, nuts, flat washers, and lock washer taking a handfull or two of each size I need to restock my bolt drawers. I worked out the cost and it comes out that I'm using all grade 8 bolts for lot less than what cheep (quality) grade 5 hardware store bolts cost.

Cheers

Hi Phil..
For those that think that the bolt grade is not that important ..I can relate an example of the importance..
A few years ago I replace a few refrigeration compressor head bolts,OEM Grade 8 with some I had around the shop ..(Grade 5)....After a month or so ,on monthly maintenance I noticed the torque check revealed they required tightening..so that was done..

The next month on the torque check..I was surprised to see that they required re torquing.....again done...

I was curious and took a good look at some new grade five bolts similiar to the new ones installed..and compared to the ones I had replaced ,but still had on the workbench in a little box(Never throw any thing out untill the missus gets on the war path..)..
I thought that the thread pitch or diameter may be slightly different,,but they checked out..OK..
With the compressor still running I pulled one of the new bolts and cranked in the old original bolt and measured the new grade 5 against the one I just pulled out and low and behold it had stretched at least an 1/8 of an inch!!!!

At 80 pounds torque and the insessant vibration ..the bolts stretched and loosened..
The same thing will happen on a carrier ..or similiar piece of vibrating machinery...Don't cheap out and save yourself a lot of hassle..use grade 8 bolts or better when it comes to your loved ones..
Bolts only stretch so far before they break..
I my case the stretched bolt caused the headgasket to leak and that is not a good thing on a refrigeration compressor..