"65 B/B Questions

[Rick Dykstra]

A couple of questions regarding my '65 as I tear into it for some minor refurbishing ; First, are the bolts that hold the exhaust manifold to the head a shouldered design with an indented face, or do they use a washer and have a circle embossed on the bolt face? Second,as I change over from a 621 bellhousing to a 403, the starter on the 621 uses a cast iron drive end housing. On the 403 style, is the end housing cast or aluminum ?, as it appears that the existing housing will not fit. Thank you in advance for your replies.

[Wayne M.]

Re: "65 B/B Questions

Rick --- Exh. manif.-to-head bolts are non-shouldered (ie. non-integral washer) design (others can speak to head markings). The bolts are all the same length, unless you have PS (not the case with the small block). Only 8 washers are used, at the exhaust ports for cylinders # 1, 7, 2, 8, because the bolt flange of the manifold is not as deep as the other ports.

Starter drive housing to be used with the "403" bellhousing is the lightweight sand-cast (could be aluminum) GM # 1968122, with the 2 bolt holes in line (L to R as mounted on motor). Remember that the smaller bellhousing also takes a different dust shield/flywheel inspection cover # 3788422.

[Robert C.]

Re: "65 B/B Questions

I think Wayne means "4" washers are used at cylinders 1,7,2, and 8. The bolts are black phosphate with the circles on the head. Originally the exhaust manifold and bolts were painted with the engine, so they could have evidence of orange paint. Bob Cook


Texas Chapter NCRS

[Rick Dykstra]

Re: "65 B/B Questions

Thanks guys, was able to get the inspection shield yesterday from the GM dealer here(still availible,number supersedes), and have the correct bolts too.What about french locks on the outer exhaust ports? and if used, do they go under or between bolt and washer? Looks like I have the correct drive housing in my parts collection, so am doing well on this job. Thanks!!

[Wayne M.]

Re: "65 B/B Questions

Rick --- Personally I don't get into this level of detail, but since it's so slow on the board, and it's raining up here, what the heck ! I assume you have the '65 NCRS Tech Manual & JG, and it does seem a little ambiguous. For small blocks, french locks at the 4 corners of the motor, but washers under ALL bolts; the spacers (washers) go between the french lock and the manifold, so the order is bolt (head) / fr.lock / washer / exh. manifold.

Surprisingly, for the 396, it doesn't mention french locks at all, but it calls for washers at the 4 corner cylinders only.

Neither does it mention a check for stainless or carbon steel material for the locks (repros seem to be SS), but I doubt the General used stainless at Flint or Tonawanda.