Jack Ramsey wrote on Sun, 14 July 2019 15:37
> I know this seems like a stupid question, but my 75 Palm Beach 455 has very few flat washers or lock washers in the engine bay. (except on the fan
> shroud) My years with German cars, and climbing radio towers, we had flat and lock washers on EVERYTHING. I went out and bought a bunch of spare
> washers, just in case, and now upon re-assembly, from the water pump out, I am wondering if this is overkill and even might be sacrificing
> reliability, by having less thread into the cast iron and other assemblies. Yes this is my first American car real work, and you would think at 66,
> I would know, but I don't. Porsche 8mm nuts (13 mm socket) had average of 18 ft lbs of torque, I'm really not used to this, it is a whole different
> world.
>
> Thanks,
>
> Jack
Jack,
SAE lock washers will seldom do any harm, but in high load situations they are quite useless. An SAE lockwasher (the kind with a sheared angled ends)
is supposed to work two ways:
First is that it is a spring to keep tension in the fastener should it have the opportunity to loose tension.
Second is that those two sharp edges are suppose to grab something and prevent the rotation of the fastener.
The only problem we (ASTM Bolting Technology Committee) found was that during an uninstrumented assembly (no torque wrench or other), the compression
of the spring in the lock washer did, in some cases, cause the assembling technician to over estimate the achieved tension in the fastener.
(Non-techese - He didn't get the screw as tight as he thought he did.)
So, put in lockwashers as long as you don't sacrifice engagement for it.
Matt
--
Matt & Mary Colie - '73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Electronically Controlled Quiet Engine Cooling Fan
OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Twixt A2 and Detroit