Why no lock-washers?

My creed is; never reinstall used lock washers anywhere on the inside of the motor, like the oil pump and if possible use new ones everywhere else. :)
 
The torque value on a fastener its the rated tension that pulls all the stretch out of the fastener,this tension holds the fastener under load without a locking device.this is why head bolts don't have lock washers

Castellated nuts and cotter pins hold a fastener assembly together,they do not hold a torque value.Backing a torqued faster off to catch a castle for pin insertion is a mistake.

Modern chemical locking compounds are superior to any mechanical locking device,like a lock washer or a castellated nut/cotter pin.
 
OK, I accept the fact that the head gasket compresses. All gaskets compress including the intake-exhaust gasket.

But still, why were no lockwashers used. You would think that in any situation were there is metal expanding and contracting a lockwasher would be used to lock that nut in place especially a place as important as the manifolds.

Mike

Because the nuts don't move, the gasket acts like a lock washer providing back pressure to the nut.
 
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How about the wheels on your car. Have you ever seen any with lock washers?
I do not think so. There are lots of places with out them.
 
another clear example of tensions effect on threads is a soda bottle..isnt the cap tight when the soda is gassy? the pressure of the soda gas puts the cap threads in tension. Thats one place on a Model A where modern techniques actually help,fastener locking. Given Ford used time management techniques to speed production IMO they would have used locking nuts and chemical locking agents instead of cotter pins and lock wire had it been available at the time.
 
If you will notice the fiber int/exh manifold gasket has a metal surface on one side. This side is placed against the manifolds to allow for movement during the heating and cooling cycle. The manifolds move much more than a person might realize and if there were lock washers installed I am sure that they would be displaced quickly and then the nuts would really be loose.
 
If you need a solution to exhaust manifold nuts backing off, you could use interference-fit brass nuts. This was a fairly common item and solution in years gone by. They would have cost a few cents more, so that's probably why Henry didn't use them :rolleyes:

Ford used brass nuts on the exhaust manifold to exhaust pipe studs on the flat head V-8s for many years.

FWIW, about 25 years ago I worked w/a fellow that was a heavy equipment mechanic that had worked for a CAT dealer for a number of years. He told me that CAT had stopped using lock washers because they had done tests that showed that fasteners stayed done up just as well w/out them as with them.
 
Those big washers on the exhaust - intake manifold attachments are cupped, so they are actually springs to cope with thermal expansion. If you repeatedly tighten those nuts, you defeat the purpose of the cup washers.
 
Picture this: On a wood base, 2 black stick figures, made from welding rod. One was a Female, with a nut for a body, she was being chased by a Male, with a screw for a body. The caption read, "NO, NOT WITHOUT A WASHER"!!----LOL
Bill Twisted
 
The cylinder head and the int/exh manifolds expand at different rates than the block so a ridged mount is not desirable as this needs to be a somewhat flexible joint.
Henry spared no expense on R&D as is observed in the amount of money spent on the 1932 60 HP V8 engine. Almost half a billion dollars. The amount of Model A research was phenomenal. You can bet that if Henry did/didn't do it that there was a very good reason for it. His idea was to pay the highest wages, use the best material, and hire the best people.
 
I agree with Bill, the guru of stuff, if you want to install them, go ahead and do it! To add to your confused state, I don't put cotter pins on rods or mains. I was a truck mechanic for many years and never found a nut actually being held on by one. In the case of the Model A engine, I believe the racing fraternity back in the day built and used a variety of heavy rods when the problem was the castellated nuts, they only have a few full threads! I raced Model B engines with B rods, turning 6200 RPM and never had a rod fail. I now use ARP nuts.
 
Picture this: On a wood base, 2 black stick figures, made from welding rod. One was a Female, with a nut for a body, she was being chased by a Male, with a screw for a body. The caption read, "NO, NOT WITHOUT A WASHER"!!----LOL
Bill Twisted

I remember them signs, they were advertising for some hardware company.
 
Chief left me a HUGE Electric Soldering Iron. It will solder a thick 1/2" flat washer to the bottom of a Coffee Can! Instead of using lockwashers, I could just SOLDER the NUTS to the BOLTS/STUDS!
Bill Hotterthanhell
 
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