The Stovebolt Site Forums The Shop Area General Truck Talk What is this fastener?

I have found this type of fastener on both the rear fenders, and again on the spare tire carrier on my 56 3600. Can anybody tell me what it is called, and what tool is used with it?

[img]http://dougherbert.org/eve/20100108%20Spare%20Tire%20Fastener/DSC_1867.JPG.preview.jpg[/img]

Thanks,
Doug

That is called a "clutch head screw" and it takes a specially-designed driver. Those things were one of the first attempts at automated, or at least speeded-up production lines, as they could be stuck onto a magnetic-tip driver, and they wouldn't fall off as easily as a slotted-head screw, or a Phillips screw. Snap-on and a few other tool manufacturers still sell those drivers, in 3 or 4 different sizes.
Jerry

those are called clutch head screws. You can get a set of 3 or 4 of them at some part houses. Even Lowe's or Home Depot have them at some stores. I suggest also trying Ace Hardware.

Most parts vendor's have them for around #20 bucks for a set.
Just as a tip.....if you round the head of them out you can stand a washer up on them, weld the washer, then twist them out.
Those Clutch heads were used on trucks for years.

I used a standard flat-tipped screwdriver to get mine out,I just got lucky that they were'nt stuck in rust or to tight.

PapaJ beat me to it. You can use a flat blade screwdriver if necessary.

Another trick is to use a cutoff wheel on a Dremel tool, and create a flat-tip slot in the screw head. Just be sure to create a tight-fitting slot for a fairly large screwdriver blade.
Jerry

Sure, all you need to work on an old truck is a hammer, screwdriver, pair of water pump pliers and a bigger hammer.

Not.

The proper tools are readily available. Why not use them? No sense in buggering up the original fasteners.

I've got a full set of clutch-head drivers. I just use the Dremel trick after some dummy with a flat-tip driver has buggered the head where nothing fits and I have to replace the screw anyway!
Jerry

OR it could be that I've never "buggered" up a clutch head screw using a flat blade screwdriver and I see no reason to spend hard earned money on a tool I don't need. I have one clutch head screwdriver I bought when I was a lad, first getting into body work and hadn't yet discovered that they aren't necessary. I don't think I've used it in 40 years. A flat blade works just fine.

.... well, between the 37 and on the 52 I have had to use practically every way mentioned..

....but mostly due to someone else not using THEIR brain!! LOL

Before I found a set at a Carisle tool booth I used a wood router bit welded to an old nut driver

I got some clutch head tips and have used them with an impact driver along with penetrating oil and heat. I have drilled out quit a few over the years. I like to replace them with stainless steel Phillip screws, looks good and easy to work with.

Having removed lots of these over the years a couple more tips.
1. Can of PB blaster a day ahead of time if possible.
2. Tighten it a bit before you try to loosen it. You would be surprised on most bolts and screws how well this works not a bunch just give it a nudge to loosen the crud in the thread paths. The other tips listed here work also as often you will find them in rough shape to begin with.

So, What is a Stove bolt?

A stove bolt is a pan head screw with a slotted head. They were used on the side covers and oilpans of Chevy engines for years, hence the nick name, Stovebolt Six.

round head, slotted, stove bolt

flat head, slotted, stove bolt

pan head, slotted, bolt

The name "stove bolt" now seems to mean any machine screw.

I have found both round head and pan head 1/4" diameter x 20 thread, 1/2" long machine screws (1/4-20 X 1/2") used to attach sheet metal on 216/235/261 engines. In the mid 1950s, it seems that hex-head machine screws, with and without a flat, Phillips-head center, became more commonly used on pans and side covers.

Maybe someone with a first-generation stove bolt engine will let us know if their screws are round headed or pan headed?

Tim, instead of the pan head, you showed the flat head twice.
(I know what it looks like, but just in case someone doesn't.)

Thanks, Rich

I've corrected the link.

Could it be that the term "Stovebolt" comes from the bolts used to manufacture the oldtime cast iron stoves? Just asking!

Martin,

You are correct. And, they were slotted round-head bolts.

Bolting was the most efficient way to assemble the cast iron parts of a wood stove. Welding the castings together was nearly impossible, and the sand-casting methods available at the time were not accurate enough to allow parts to be snapped together into a sturdy assembly. The combination of a round-headed machine screw and a square nut was cheap, and easily tightened with common household tools like a flat-blade screwdriver and pliers, or even a table knife in a pinch. The term "stove bolt" got applied to round-headed machine screws with a coarse thread, like 3/16" or 1/4" screws. When Chevy started attaching sheet metal parts to their engines with slotted-head 1/4" screws, the "stovebolt" name was a natural fit.
Jerry

I purchased the bits from one of the vendors. I put the bit in my cordless drill and turned the torque setting down until it acted like a hammer and backed out all of the clutch heads on the inside of the cab. I would have bet that several would have had to be drilled out, but they all came out just fine.

I got a set of the screw drivers at a good price from Jim Carter. Not as good as Snap on. But they work for me since most of my clutch heads screws seem to be in the interior cab.

My plan worked very well. I just cut them off with a grinder and replaced them with button head hex bolts. Unless you are trying to restore to original I wouldn't waste my time trying to unscrew an old rusted bolt.

I just think they are cool. I will probably replace the fender to bed screws with something else. I am sure they aren't gonna come out without a fight.

Stainless-steel rear-fender-to-bedside clutch-head screws are available from a few vendors.

I just fastened my second fender yesterday with those SS clutch head screws. I have 3 sizes of clutch head drivers but they were all too small. I fabricated a bigger driver, worked very well.

Yes, those fender bolts and some door-latch bolts require the "4th" clutch-head driver that comes in some clutch-head drivers and bits sets.

Finally- that's what it's called. Thanks Boys! I'm finding that 40years in a barn equals a lot of cut-off wheels! HAHAHA

If you don't have a clutch head driver you can often substitute a flat blade screw driver.