Upper crankcase bolt for 47 FL...

[BONES47FL]

O.K., I got confused with my parts manual. What is the correct length crankcase bolt for the upper stud, (the one that will hold the speedo cable clip and carb bracket) ; 5/16 x 5 7/8 or 5/16 x 6 ? Or some other length? Thanks, BONES

[D.Mac]

Top crankcase stud

Bones,
I was just fixing to install the correct speedo cable clip on my early Pan, and I had to get a 6" length to have enough meat for it. I think your Knuck would be the same. My parts book is not very clear regarding the top stud part number, the rest of the studs are identified better, and have lengths listed. I ordered a part# 24809-30 from Old Dude, should be here any day.
Doug.

[BONES47FL]

crankcase bolt....

Thanks Doug, for the reply. I guess I'll call Bart up and score me one! Bones

[oldsouthmcy]

Bones, Doug,

Pan cases are wider than knuck cases at the upper crankcase stud. Pan cases are 4-11/16" to 4-3/4" wide. Knuck cases are 4-1/4" wide. So there are two different top studs for these motors.

The problem you may be running into is the illustration of 24805-30 (446-30) in the top position of the BTSV case and 24807-48 (447-48) over the OHV case in later parts books. The correct stud for a knuck case at the top position is 24806-36 (447-36). A knuck case uses two 447-36 studs, one at the top or 12 o'clock position and the other at the 1 o'clock position.

The parts book lists 447-36 as being 5-7/16" long. The ones on my motors have been 5-9/16" long. With double stacked nuts at the speedo clamp, the 1/4" difference could be an issue. (447-48 is 5-7/8" long and I have no issue with it on a 48 pan here.)

Not so sure you should try using 24809-30 (446-30) in either a pan or knuck in the top position. First, it is not threaded enough for the extra nuts, speedo clamp, and carb bracket as are 447-36 and 447-48. Second, the 446-30 is a locating pin and should be too large in diameter for the top hole. If forced in, it is possible it could crack the case.