Borg Warner Velvet Drive 71c stuck in gear

Michael Riebs

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Auburn, WA
Greetings everyone,

Yes, I see another thread with the same heading, but it doesn't seem to address the issue(s) I am experiencing, so here goes:

I am a recent owner of a 1986 Century 300 Cortez Grande with twin 260 Hp Chevy 350's coupled to Borg-Warner 71c (as far as I can discern) Velvet Drives. The boat was known to have some issues when purchased, but I am running into more issues than I expected.

As the tale goes:
The Port rudder was "sheared off" at the hull when it was hauled out of the water, and would need to be replaced. The entire rudder blade is non-existent.
Starboard propeller was badly bent, and one blade torn about 2" from the edge and also folded back. Would likely need to be replaced.
The engines both started, although the Starboard engine needed a bit of persuasion with some gasoline poured directly into it - but then ran for several minutes.

Fast forward to post-purchase restoration:
Apparently the Starboard rudder was also damaged to the point of needing to be replaced. Luckily, the owner of Skagen Boats in Auburn, WA has a friend who owns the foundry that produced the rudders for these, and many other boats in those days, still has the foundry, and the patterns. Cost: $700 - EACH....

Taking the damaged propeller to Tacoma Propeller reveals that it is not repairable, and they were curious as to the condition of the shaft, given the damage to the prop. Cost of replacement from Michigan Propeller is $896. (Nibral 15RH17 1.25">1" taper).
Needing a 2nd opinion, I took it to Sound Propeller, who initially said "everything is repairable", but ultimately said that there was damage in the shaft tunnel, and it was not reparable - and the shaft was likely damaged as well - have it checked.

At the boat, the Port shaft moves freely (trans in neutral), but the Starboard shaft won't budge.
The shifter for Port moves happily back and forth - Starboard won't budge.
Check transmission fluid: Port is full, Starboard is completely dry - and the shift mechanism is stuck in place.

I have been reading several threads about "similar" issues, this thread included, but none seem to address what happens when the transmission is bone dry - and whether it might just "snap back" when being introduced to 2 quarts of Dextron F (plus what goes in the cooler).

So, please, help me figure out what happened when the propeller was damaged so badly - did the transmission get fried at that time too? Why is it completely dry? Cracked housing? Is there any hope that I might get out of this issue without buying a new transmission? I have found rebuild kits for the 71c for around $150...

Thank you for any help you can offer.
 
Sorry, I missed the bit about no oil. The oil cooler is most likely where the oil went; it must be leaking. The frozen shift valve sounds like its corroded in place.
 
There is no way around it. Take off the transmission, disassemble it and inspect for damage.
 
There is no way around it. Take off the transmission, disassemble it and inspect for damage.

That's what I was afraid of...

What if, as Brendan said, the lever is corroded in place - how do I "un-corrode" the lever? And I've read in other forums that the clutches won't disengage without starting the engines, so that oil pressure is applied - is there something along this line I could try BEFORE ripping out the transmission, that could indicate functionality?
 
gonzo is right. It needs to come out and be stripped down. How did the boat sustain so much damage? did it hit a reef?

I don't know how it sustained all the damage. I bought it about 6 weeks ago, and the story I was told about its condition (specifically the Borg Warner) doesn't quite line up with what I am now seeing.

I was told that the rudder was sheared off 2 years earlier by the incompetence of whomever pulled it out of the water. I was never told anything about how the propeller sustained the irreparable damage, or how the starboard rudder shaft was bent beyond repair - and all I knew about the transmission was that the seller had disconnected the cable before he had started the engine to show me it runs - and reconnected it after I bought the boat.

Now that I have taken the badly damaged propeller to various prop shops, they, and others knowlegable on this - are all asking me whether the shaft is damaged, and recommending I take it in to have it examined, and possibly trued, if necessary.

The shaft does not turn - not even after applying force using a pipe wrench - so I went in search of the cause.
The shifter does not move at all The port shifter moves freely, and the shaft spins freely - so I tried moving the shifter lever at the housing - still won't budge. I have not yet taken the cable off the lever to find out whether it's a stuck cable, or a stuck lever - but I will do that today.

When I found the lever stuck, and learned of the transmission dipstick, I checked for oil. The port dipstick indicates good, but used oil. The starboard dipstick was bone dry.

Yesterday I learned that there are 2 oil reservoirs, and 2 dipsticks - one for the transmission and one for the V-drive. I don't know which one I pulled, not knowing there were 2 - but I will find out today, and examine the other one. I believe it was the V-drive dipstick - the one closest to the shaft, but I'll find out and update here later tonight.

I truly appreciate all the help you guys are offering @brendan gardam and @gonzo

Michael.
 
What you are describing sounds like fraud. You should probably contact a lawyer before spending any money or disassembling anything.
 
What you are describing sounds like fraud. You should probably contact a lawyer before spending any money or disassembling anything.
Wise comment! Also have it inspected and get a written statement by an independent professional; surveyor or marine engineer before you continue.
 
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