1965 396

[Jimmy G.]

What are the correct bolts for the oil pan on a 396 ?? What about the crankshaft pulley to harmonic balancer ?? What about head bolts ?? While I am asking, what about the correct style of intake bolts also. ??

[Bill W.]

Re: 1965 396

Ok Jimmy here is what was on #16120 crankshaft pulley to balancer is a 9/16 flat head with a "C" and 3 lines 1" thread . Oil pan is a 1/2 flat head with a U and a captive star washer with 12 points about 5/8 thread . The intake is a 9/16 flat head with a 3 lines and a small circle with an "A" in the center it also has the thick built in washer (about a full 1/16 thick)thread is 1 1/4 long total length 1 5/8 . head bolt has a 5/8 recessed head with a captive washer and a circle in the center 4 1/8 long thread . There were two more long head bolts in the bag from 16120 they were flat head with a captive washer and a C with 6 lines . I hope this helps . What is the vin on your 396 . Bill

[Joe L.]

Re: 1965 396

Ok Jimmy here is what was on #16120 crankshaft pulley to balancer is a 9/16 flat head with a "C" and 3 lines 1" thread . Oil pan is a 1/2 flat head with a U and a captive star washer with 12 points about 5/8 thread . The intake is a 9/16 flat head with a 3 lines and a small circle with an "A" in the center it also has the thick built in washer (about a full 1/16 thick)thread is 1 1/4 long total length 1 5/8 . head bolt has a 5/8 recessed head with a captive washer and a circle in the center 4 1/8 long thread . There were two more long head bolts in the bag from 16120 they were flat head with a captive washer and a C with 6 lines . I hope this helps . What is the vin on your 396 . Bill

Bill------


The balancer bolt and intake manifold bolts sound right. However, I've never seen an original big block head bolt with anything but a raised cross headmarking. On original bolts, the ends of the cross extend all the way to the perimeter. On later SERVICE bolts, the ends stop short of the perimeter.

[Bill W.]

Re: 1965 396

Joe I only cleaned one bolt to check . This engine was removed at about 1 year old and not touched until I bought it . Could the early ones have had different head bolts ? I will check some of the other ones . It also had the first design main bearing bolts that hold the windage tray with bolts instead of nuts .

[Joe L.]

Re: 1965 396

Joe I only cleaned one bolt to check . This engine was removed at about 1 year old and not touched until I bought it . Could the early ones have had different head bolts ? I will check some of the other ones . It also had the first design main bearing bolts that hold the windage tray with bolts instead of nuts .

Bill-------


I would not rule it out but, if so, it's a configuration I've never seen. It's also contrary to what GM says the head configuration was for the 1965 bolt part numbers.

As far as the main bearing studs are concerned, the configuration you describe is GM #3866972. These were used for the 1965 and 1966 model years. It's also possible they were used for very early 1967.

[Wayne M.]

Re: 1965 396

Joe I only cleaned one bolt to check . This engine was removed at about 1 year old and not touched until I bought it . Could the early ones have had different head bolts ? I will check some of the other ones . It also had the first design main bearing bolts that hold the windage tray with bolts instead of nuts .

Here's a shot I took a few years ago of the 3 variations in head bolts off a 396 block. The orange ones are the "shorties". I'm not saying they're correct or not. I didn't take off a valve cover to check all the long ones.



c

[Mike M.]

Re: 1965 396

dsi'm familiar with the "M" recessed hex head bolt as thats whats on my 396. thanks wayne. mike

[Bill W.]

Re: 1965 396

Joe I checked 10 more bolts and they are all the same . The engine still had the steel head gaskets on it when I took it apart . and was a year old when removed ?

[Wayne M.]

Re: 1965 396

What are the correct bolts for the oil pan on a 396 ?? ----

Here's the pan bolts from a mid-May '65 cast 396 2-bolt pan. 16 of the 20 were the "U", as Bill describes. Then there were 2 with what I believe is the STELCO (Canada ?) symbol. Then a Dexion (?) and one with a recessed head and a "L" with 3 marks at the perimeter. The 2 Stelco's and the Dexion have integral cast teeth on the underside of the head (rather than a captured star washer). I've never seen this before.

[Carl N.]

Re: 1965 396

Have seen all of examples shown over the years on L78 plus the limited 396 in Chevelles and the 396's in full size cars. I would suspect these bolts were not limited to the L78 cars.

[Jimmy G.]

Re: 1965 396

If you know of any extra short ones or where to find them I would be grateful

[Joe L.]

Re: 1965 396

Have seen all of examples shown over the years on L78 plus the limited 396 in Chevelles and the 396's in full size cars. I would suspect these bolts were not limited to the L78 cars.

Carl------


They were absolutely not unique to L-78's. The same bolts were used for all Mark IV big blocks.