Engine Mounts Bolt

[Chris H.]

Re: Engine Mounts Bolt

I dug up my December ‘68 L71 bolts. 16F8904F-2142-4FEF-8A0A-F9B31F73D7A3.jpg94E3269B-3783-4E3A-BD8D-B314A2F2A9B5.jpgDC9A8204-6273-4A08-87A1-B06DD5F60484.jpg

[Chris H.]

Re: Engine Mounts Bolt

And mount to block bolt.4D314567-4817-4FEE-A363-A78F608C343B.jpeg

[Joe L.]

Re: Engine Mounts Bolt

I dug up my December ‘68 L71 bolts. [ATTACH=CONFIG]101826[/ATTACH][ATTACH=CONFIG]101825[/ATTACH][ATTACH=CONFIG]101827[/ATTACH]

Chris------

This is exactly what I would expect for 1963-69. Looks like the zinc plating on the bolt and nut is gone, though.

[Joe L.]

Re: Engine Mounts Bolt

And mount to block bolt.[ATTACH=CONFIG]101832[/ATTACH]

Chris------

Exactly what I would expect for 1963-82.

[Chris H.]

Re: Engine Mounts Bolt

Yes Joe, being here in the Northeast there was a fair amount of aging so I cleaned them up on the wire wheel.

[Orjan S.]

Re: Engine Mounts Bolt

Chris.
Thanks for the nice photos.
Joe.
Thanks for great information.

Orjan.

[David L.]

Re: Engine Mounts Bolt

Attached are photos of engine mount bolts from a 1966 Chevrolet 283 engine that I removed from a salvage yard on the Chelmsford/Westford, Massachusetts town line on 12/01/1984. The grade 5 bolts are 7/16"-20 X 3 7/8" w/tapered ends (GM # 3817224), 4 washers, 0.91" O.D., 0.50" I.D., 0.075" thick (GM # 103342), and 2 Marsden 7/16"-20 nuts (GM #272876). The bolt heads have the "RSC" logo with 3 radial line segments. The same part numbers appear in my 1966 Chevrolet and 1966 Corvette Assembly Manuals.
Dave

[Gary B.]

Re: Engine Mounts Bolt

Dave,

Lots of the RSC headmark bolts on ‘66 and ‘67 Corvette.

Gary

[David L.]

Re: Engine Mounts Bolt

Gary.
Yes.....logo, headmark, whatever..... it's on the head of the bolts in the 2nd photo. Over the last 40 years I have seen the same bolts with "UR", "A", and "F" on the bolt head as per my notes, probably mostly on Chevrolet models.
Dave

[Gary B.]

Re: Engine Mounts Bolt

Dave,

The 3rd letter is hard to make out in the 2nd photo. But it’s a C.

Gary

[David L.]

Re: Engine Mounts Bolt

Dave,

I only brought it up because the 3rd letter is hard to make out in the 2nd photos do some people might believe the C is a B given the text.

Gary

Gary,
Yes.....Thanks for the wake up call. The bolts have "R", "S", and "C" on the headmark. I just made the correction.
Thanks again.
Dave

[Gary B.]

Re: Engine Mounts Bolt

Super. Thanks. I forgot about the edit feature. That keeps the record more straightforward.

Gary