Transmission seal replacement

[Jflr]

Lehman 135 , Borg Warner velvet drive transmission. Prop turns clockwise. I have a small transmission leak and want to change the seal.
My problem is I can’t tell if the 1 11/16” nut holding the flange to the transmission shaft is a reverse thread. It won’t move in either direction easily and I don’t want to use more force until I’m sure. There aren’t any threads protruding from the nut to tell. Can anyone tell me whether it is a left or right hand thread? Can I use heat on it to help loosen if necessary?

 

[Comodave]

I would use an impact first. I have a 1/2” impact that would probably break it loose.

 

[jleonard]

I don’t remember what the torque is on that nut but its a lot. I used a long piece of angle iron and two bolts to hold the flange ( braced against the floor) and a long breaker bar with a pipe attached to loosen ( and tighten) the nut. I believe it was a standard thread.

 

[SteveK]

Had a look at my service manual and only one nut is listed in parts which suggests CW thread

 

[Jflr]

Thank you for the quick replies. The specified torque is a lot, 200 to 250. I have bolted some iron to the flange to steady it and I have a long breaker bar and pipe. I’ll give it another try tomorrow and assume it’s a standard thread. If I can’t move it, will applying heat help (or hurt)?

 

[Jflr]

I would use an impact first. I have a 1/2” impact that would probably break it loose.

Good idea, but I don’t think I have the clearance because of the prop shaft.

 

[Mac2]

Not familiar with that transmission, but it seems like there should be a bearing on that spinning flange. I would be worried about melting the grease out when applying heat. A parts break down should show any bearing in that area. Otherwise, heat would definitely help. Might be a matter of ordering a bearing to have on hand just in case.

 

[jleonard]

One thing i just remembered is to put sealant on the splines when you re assemble the flange. This will prevent oil from leaking thru the splines. Got that tip from a then old timer at my local velvet drive distributor.