Re: The Duchess Project: 1940 Super 8 Convertible Sedan

Posted by Joe Santana On 2017/10/19 15:15:35

Frustrated this morning. The "completed" engine was picked up and is in Salem with my son, so I can't look at it. But I'm told one of the outer (longer) manifold studs is broken and my son asked if I could get a new one.

Checking the parts book where I could not find a listing for the Block (the engine section starts by listing the camshaft), which I thought was weird. Didn't anyone need to order a replacement block?

Anyway I found the section for the manifolds. No studs are listed in intake or exhaust, only machine screws listed in the exhaust section (shared with the intake manifold).

There are 3 #300136, which is listed Nowhere in the 50.003 machine screw utility item section, and 3-#7243 listed in 50.003 which are 3/8" - 16/in thread, 1-1/8" long hex-head machine screws.

Question 1: Since there's no listing for 300136, is the 1-1/8" 7243 the longer or shorter of the two sizes.

What's also weird to me is that the nuts are 3/8 ID, 7/16 OD, 13/32 thick 24/in thread. And listed as BRASS. Son says these need to be Grade 8 steel.

Question 2: If there are no studs associated with the manifold (except the 4 holding the carburetor) why are the nuts listed 24 threads/in? Are they for the carburetor only?

Son John says that the rebuilt '47 356 engine and the '40 356 engine both have studs for the manifolds, not machine screws. As soon as he gets home from work he'll remove and measure the good outer stud.

Question 3: Should we replace the studs with 16-thread machine screws?

Help here would be much appreciated, especially in using the Parts Book if I'm doing it wrong. - Joe