MGB Starter bolts

[Coastalman]

Today I am working on installing the starter on my project 66 B. All the bolts that came in the Moss package to put the transmission to the back of the engine are 1/2 inch. I used a 1/2 inch bolt on the upper hole of the starter to mount it to the engine plate and bell housing. The lower bolt goes into a a hole that ends in an enclosed part of the bell housing. The half inch bolt will go into that hole, but will not tighten up. I tried a 9/16 bolt and it will start, but not go very far.
What is the correct bolt to go into that lower mounting for the starter? Could the threads be stripped?

Thanks
Charlie

 

[Mickey Richaud]

Hey, Charlie -

The top and bottom bolts are different threads, but both are 3/8" diameter thread. I believe the top is coarse thread, 3/8 X 1 3/4" long; the bottom is fine thread (24 tpi), 3/8 X 1". Remember, if bolts are threaded into aluminum, they are usually coarse-threaded; steel, usually fine. Don't forget the lock washers.

 

[Coastalman]

Thanks Mickey! I'll try the different bolt tomorrow. I knew there had to be an explanation.

 

[bobhustead]

Note that Mickey is talking about diameter of the bolt and Coastalman is arrarently talking about the head size. Bear that in mind as you try new fasteners.
Bob

 

[Mickey Richaud]

Note that Mickey is talking about diameter of the bolt and Coastalman is arrarently talking about the head size. Bear that in mind as you try new fasteners.
Bob

Thanks clarifying that, Bob.
Mickey

 

[Coastalman]

The right bolt was sourced and installed. Thanks to all for giving me the information I needed. I question myself when all the other bolts work just fine and one does not. Thank you BMC for keeping my life from being trouble free. Among many other things.