Gearcase Head Screws 1963 75hp

[yorab]

Is there anything special about the gearcase head (commonly referred to as the prop shaft bearing carrier) screws? I see that they have separate seals under the heads to seal the gearcase, but they seem like ordinary screws. They are part #308211.

My screws are ok, but they have slotted heads and some of the slots are a bit sloppy. Since I'm rebuilding, I'd like to replace them. I see that list price for these is about $8.50 and I'll need 4 of them at that price. That's a bit too much if I can replace with aftermarket screws for about 1/10 of the cost and the same quality.

Does anybody know why they are slotted as opposed to hex cap or socket cap screws?

The screws are #59 in the picture. Thanks.

 

[oldcatamount]

Re: Gearcase Head Screws 1963 75hp

I think you'll find they are stainless steel and you probably should use stainless steel. Whether they are slotted head or not wouldn't make any difference.

 

[captk]

Re: Gearcase Head Screws 1963 75hp

Thay are slotted cause back in them olden days thats what they used. If they have a concave head to hold the seal I would only use oem screws. They have to seal that gearcase and those electric g/cases dont like water.

 

[F_R]

Re: Gearcase Head Screws 1963 75hp

They are so expensive because they are special screws. They have a groove on the oil-side for the o-ring. Don't be so picky about the slots. Simply use new o-rings. Unless you really, really, really care what they look like. Then pay the $8.50.

 

[yorab]

Re: Gearcase Head Screws 1963 75hp

No, I don't care so much about what they look like since they're hidden behind the prop anyway. I was just a bit worried about stripping the head slot and not being able to get them off in the future, if I ever need to. That is why I was leaning toward a socket head cap screw. But now that I know that it is a special screw, I certainly won't be going to Grainger or Fastenal.

The slots aren't too bad though, and I should be able to reuse the original screws unless they need to be cranked down to some ridiculous torque value. In that case, the slot might get stripped. Does anybody know the torque for these? Are they the same as for other screws of the same size on that motor?

 

[F_R]

Re: Gearcase Head Screws 1963 75hp

The book doesn't specify a torque value for those screws, so that leaves it at the generalized value for 1/4" screws which is 60-80 inch pounds.