Paging Sandy and other inboard tranny experts

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VTBoater

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Guys,
I struggled pretty badly today. Removed the shaft coupler, and need to remove the output flange to change the blown seal on the transmission. I tried to remove the large nut on the flange with a 3/4 inch drive socket set, and could not get it to budge. The flange wants to turn, it is very hard to secure it in place in the boat. What am i missing?
How do you get the flange to stay steady, and is the nut standard thread or reverse thread?
I even thought about attempting to remove the whole tranny end case, but worried I was opening a larger can of worms.
 
James- For clarification I'm not an expert at anything though sometimes I use words longer that 5 or 6 letters just to impress myself.

Holding that thought, I'm afraid I've never removed an output flange. Maybe if you post the model of transmission there is a bit of a chance we (anybody) can find an illustration of the setup. I don't recall seeing a large nut on the output shaft of my VD 72C's but there are bolt heads on the reduction gear side of the DriveSaver coupler on mine that are going to be a bear to remove.

Here's a pic of the output shaft end of a VD 71C in case that's what you have with your Crusaders.
http://www.michiganmotorz.com/velvet-drive-transmissions-remanufactured-p-855.html

But I suspect you may have ZF/Hurth transmissions as they do appear to have an output flange held by a large nut. Can you see any threads at all on the nut or shaft to inspect closely to tell if they are lefty or righty? Do you have any metal bar or "L" stock you could drill holes to accept bolt and nuts so the bolts can continue into 2 contiguous holes on the flange to wedge it in stable position while you whack on the breaker bar w/ socket once you confirm loosey direction? The stabilizer may not be necessary once you know the direction and just whack the breaker bar a few times .

No idea about the ZF's, but on the VD 71C & 72C straights at least, one can pull the aft spring-loaded seal and replace externally once the coupler is out of the way. (I've only seen that done by a marine mechanic friend.)

Sorry I'm not providing much help but I think I see a J-D, Old Houseboater, Charlie, Thuddie and a posse of much wiser minds headed your way
 
First, I don't recommend beating on it with a puller. I have read where that can damage the interior parts of the trans. Second, in this type of situation, I like to lock a vice-grip on the part and position it against a board resting on the hull. If that isn't convenient, bolt a longer bar to it as Sandy suggests. You might have to fabricate your own bar. Some times a 2x4 is an adequate bar.
 
Count me out. I've never used "Contiguous" in a sentence. "Adjacent," maybe. But I liked a girl whose dad was a ball bearing salesman. He used the term "brinelling" for indentation damage to bearing surfaces from severe impact or even vibration during times the bearing was not rotating. I think he should have said "false brinelling" to describe that damage condition, since WIKI says "Brinelling" is a formal lab test for hardness. And I thought I'd better be able to spell it correctly. Anyhow, the output of a transmission screams "Thrust Bearing" and there's no way I'd beat on it. Beyond that, I can observe from front crankshaft "pulleys" (actually Vibration Dampers) that they feel like a press fit pulling off but turn out to be a slip fit that got stuck over the years. So it's at least possible that once off and all surfaces cleaned it'll be easier to reinstall. Please try to find Make/Model/Year of the Transmission and post that info. I haven't worked on one but may be able to find somebody who has.
 
OK,
I am going back after work today and will attempt to get a model and serial number off them.
 
ill assume its a borg 71 or 72 reduction gear if so remove the reduction housing put it up on a bench and use an impact dricer to remove the nut or better yet take that part to someone that knows what it is and how to change the seal and retorque the flange nut
 
So if you remove the whole reduction housing, there is no shaft connected to the end flange, it will just come right off?
 
If it's in fact a BW Velvet Drive, I found a manual you can view online

http://l-36.com/read_pdf.php?file=manuals/Borg-Warner-71C-72C-Transmission-Manual&title='Borg-Warner%2071C-72C%20Transmission%20Manual'
 
Let me make myself clear. I meant to attach the vice-grip to keep the transmission from turning while trying to remove the 3/4 inch drive. I didn't mean to attach the vise-grip and then beat the vice-grip. That's the same as beating the transmission flange itself. The vice-grip just keeps everything from turning.
 
So I took the whole reduction gear case off. Brought it home and was able to put my air impact wrench on the nut, it came right off. the flange then came right off. Good thing because I did damage it a little around the bolt holes trying to hold it steady while attempting to remove the nut.
I will drop it off at the machine shop with the couplers, the machinist wanted the couplers with the shafts.
Thanks for the advice all, looks like I am making progress toward repairing these issues.
 
Waytogo!
Progress is one of those especially good longer words.
 
don,t forget to seal the splines on the inside of the coupler when reassembling
 
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