Velvet Drive Maintenance

Bob Giaier · Post by **Bob Giaier** » Wed Oct 31, 2012 8:20 pm

I hope the east coasters on this forum have made it thru the storm with you, your family and your Trojans unharmed.

I have a maintenance question concerning the Velvet Drive. My 73 Tricabin has ASll 72C's with 1.1:1 reduction. As far as I know the trans fluid has never been changed, so I pan to do this on Friday. I have the manual (thank you forum members for making that available). The 71C-72C manual only talks about changing the fluid. The older manual 70-71 explains to also remove and clean the strainer on the Velvet drive fluid inlet from the cooler, but the new manual doesn't mention this.

Is there a strainer screen on the 72C and if there is, should I try to remove it and clean it?

Thank you in advance for all your help.

aweimer · Post by **aweimer** » Wed Oct 31, 2012 9:40 pm

I just change the fluid. The cooler can be cleaned out too but honestly if your not having any issues with it I wouldn't bother.

Changing the fluid did really smooth out the shifting in mine. I used Type-F trans fluid. Took just over 2 quarts.

Bob Giaier · Post by **Bob Giaier** » Thu Nov 01, 2012 7:45 pm

Thanks for the note Aaron, I do plan to clean the heat exchangers. I cleaned one of the engine heat exchangers and found impeller pieces and small weed leafs.

The drives work perfectly, and I'm accused of being an over-maintainer, sometimes causing my own problems, so I won't pull the strainers on the velvet drives.

By the way, your forum pics are great - your tri cabin looks beautiful. My 73 is nearly identical to yours.

Thanks again,
Bob

aweimer · Post by **aweimer** » Thu Nov 01, 2012 8:40 pm

Thanks I need to update those. That is what she looked like when I bought her.

I've updated the aft bath counter to black marble. Installed all new carpet inside. Refinished all the exterior teak. Had the bottom blasted and reconditioned.

This winter I'm working on adding a 2nd AC in the aft cabin. I'm taking the electric wall heater out from below the ladder in the back, installing a Marinaire 9k unit up there and venting out on each side of the bunks. Should really help keep the summer comfortable.

Hope all goes well with your maintenance work. This spring I'm going to change the oil in the V-Drives.

larryeddington · Post by **larryeddington** » Thu Nov 01, 2012 9:11 pm

use type F or dexron in Paragon pv31 vdrives? In the old days we would use type F in GM as has more friction material and would slip less then dexron.

someone give me a clue.

aweimer · Post by **aweimer** » Fri Nov 02, 2012 8:50 am

larryeddington wrote:use type F or dexron in Paragon pv31 vdrives? In the old days we would use type F in GM as has more friction material and would slip less then dexron.

someone give me a clue.

Type F based on my manual that i have.

gettaway · Post by **gettaway** » Fri Nov 02, 2012 11:14 am

Depending on how you plan to drain the old fluid, you'll probably remove the strainer anyways, it's just a screen tube and it only takes a quick spray with brake clean or similar cleaner to clean it out, and I'll bet you it is clean anyways.

Bob Giaier · Post by **Bob Giaier** » Sat Nov 03, 2012 8:36 am

Air conditioning in the aft cabin sound like a great idea. I guess you can put your fan away. I added a aft deck hatch for an achor and a returnable can (I collect used beer cans in this nicely hidden location). Not sure an AC unit will fit there now.

Thanks for the info guys on the F type fluid. Owners manual calls out Dextron, Maintenance manual calls for "Dextron, type F". I vacuumed the fluid out (like changing engine oil) and the cooler hoses were dry, only the heat exchanger had fluid in it, so there was no mess involved in the whole operation. I'll check the strainers next time I'm up.

I'm finding lots of impeller chunks in the heat exchangers. Of course, I changed all of them when I bought the boat 3 years ago. How often do you guys change the impellers? My guess would be 4 -5 years so as not to encounter exploding impeller parts throughout the engine.

by the way I changed the oil in the starboard V drive too. The vaccuum method wouldn't work. Either the oil was too thick for the pump or I couldn't get the pick up tube in the oil resevoir. Aaoron, when you do this in the spring, use the higher up drain plug first (there are 2 upper ones), it will lesson the potential of making a mess, since the actual smaller lower drain plug is difficult to get a collection pan under it. Also, the manual calls for 3 pints and mine reads full with 2 pints? I didn't need to do the port V drive since i repaired the heat excahnger last year (that could be another posting if anyone is interested in how that was done with West Systems).

Thanks again,

Bob