Snap-on S-8663 Obstruction Wrench
 

I saw two Snap-on S-8663 Model A Obstruction Head nut wrenches on e-bay today for good prices if anyone is interested. Not mine.

One looks really nice date coded 1959. https://www.ebay.com/itm/297388963592. The other has some wear, date coded 1954. https://www.ebay.com/itm/236141745480.

Re: Snap-on S-8663 Obstruction Wrench
 

What's an obstruction wrench? I was a truck mechanic for 20 years and never heard that description before.

Re: Snap-on S-8663 Obstruction Wrench
 

It is a wrench that is bent to fit around obstructions so you can get the proper torque on the fastener. In this case the Model A distributor and carburetor.

I just looked it up in my 1980 Snap-on Catalog, Called a Cylinder Head Wrench/Torque Adaptor. "Designed for getting around obstructions and reaching into restricted areas when removing or torquing cylinder heads.


The nice one I referred to already sold.

https://www.fordbarn.com/forum/attac...9&d=1749752001

Re: Snap-on S-8663 Obstruction Wrench
 

I picked up one of these at an estate sale. Still sealed in the original package $5.
https://www.ebay.ca/itm/151574867052
I had been using my aircraft cylinder wrenches but they are pretty tall.



I also bought one of these little electronic torque wrenches at HF for the road tool kit.

Re: Snap-on S-8663 Obstruction Wrench
 

Another picture of a Snap-On S-8663-B Obstruction Wrench.

https://live.staticflickr.com/65535/...8092fab7_z.jpg

Re: Snap-on S-8663 Obstruction Wrench
 

I made my own. 11/16 box-end, open-end combination wrench, 1/2-inch drive to 3/8-inch drive reducer, square tube. I tried it first with just the bent wrench but it was too flimsy and I needed a longer version.

Re: Snap-on S-8663 Obstruction Wrench
 

https://www.fordbarn.com/forum/attac...p;d=1749768957

Home made 11/16 box end open end combination wrench - nkaminar

Re: Snap-on S-8663 Obstruction Wrench
 

Is that a piece of heavy angle between the wrench parts?

Re: Snap-on S-8663 Obstruction Wrench
 

I think he mentioned square tubing...

Re: Snap-on S-8663 Obstruction Wrench
 

Snap-On (especially old) stuff is lovely. I have a few. But as far as the head torque adapter, hard to beat the one Snyder's sells.

BTW, when I was growing up we knew these distributor wrenches, designed to get around the distributor body and to the bolt that was loosened to adjust timing.

Re: Snap-on S-8663 Obstruction Wrench
 

Just wondering- has anyone ever done a test to see if these angles affect the torque value at all?

Re: Snap-on S-8663 Obstruction Wrench
 

The socket portion of the adapter is directly in line with the square hole for the torque wrench. No lateral displacement = no change in torque value.

Re: Snap-on S-8663 Obstruction Wrench
 

I have a few of those.We always called them torque adapters.Lots of farm and industrial equipment are built with a need for them.Continental and Perkins have head nuts tucked in between the pushrod tubes.Case had an odd casting overhang that required the use of them.On a John Deere engine mounted on an industrial stand you can't tighten the front main bolts without one of those.The smaller ones I kind of consider distributer and vacuum pump wrenches.The 11/16 through 1-1/8 are much beefier,and used for heads and mains.Instead of buying the whole set over 40 years ago,I bought one at a time as needed,and now I have the whole set.Probably cost me double that way.

Re: Snap-on S-8663 Obstruction Wrench
 

Bruce, Square tubing. Any tubing will carry more torque than any angle iron. I had to bend the wrench parts to get everything in alignment because I was using it with a torque wrench. The wrench parts have to be heated to dull red to bend.

Re: Snap-on S-8663 Obstruction Wrench
 

ooops!

Re: Snap-on S-8663 Obstruction Wrench
 

i dug around in the junk and came up with some old broken sockets and some 5/16 x 1 flat bar and fabricated mine. you can pickup used sockets at a yard sale or flea market and make one cheap. i like fabricating my own A tools when i can, certain satisfaction in doing so. i even copied a rear brake drum puller a friend had made years ago. it is simple but does a good job.

Re: Snap-on S-8663 Obstruction Wrench
 

I've got several of the genuine Snap-On tools, $50 post paid to anywhere.

Re: Snap-on S-8663 Obstruction Wrench
 

Pretty much all of the aircraft engine manufacturers used the odd shapped tools such as these to remove various assemblies such as cylinders, tappet blocks , and even push rod tubes from the old radial engines as well as the opposed types. They were very common in aviation. Lycoming and Continental still use them.

Re: Snap-on S-8663 Obstruction Wrench
 

I have several snap on tools can somebody explain how you read the date on them.

Re: Snap-on S-8663 Obstruction Wrench
 

Try this: https://www.google.com/search?q=snap...hrome&ie=UTF-8