What would happen to my Velvet Drives?

Obaby · Post by **Obaby** » Fri Aug 22, 2008 1:33 pm

One feature about my 11 Meter helm I dislike is how close my Morse Shifters are to the cabin entryway handrail.

I'm cruising this weekend with 8 people onboard at 19 Knots and all I kept thinking was someone stumbling while reaching for the handrail and shifting me into reverse at 3800 rpm.

Would it even engage into reverse at high RPMS ?? or would I have time to react ?

Any Velvet drive experts have any thoughts?

Anyhow, it's something thats always bugged me and I'm sure not going to test my theory !!

Boat is running awesome though !
Thanks
Patrick

Heck I might even secure the shift controls to an eye clip, then un-clip when needed.. It's better than the stress it causes...!

prowlersfish · Post by **prowlersfish** » Fri Aug 22, 2008 5:06 pm

Hard to say , some are rated to stand a full power reverse. I can tell you my ZF220A gears will take a full power reverse and back to foward at WOT . I was responding to a mayday at WOT and almost something in the water so full reverse then back to foward engine stay at WOT . Idid not even think about the the engines being at WOT , my mind was on the mayday (heart beating a mile a minite and the top of the boat in sight) aftewards I realised what I did. I looked for damage none found I have put 400 hours on them sence no proplems.

I was able to get both people out the water so even if I did blow a gear box it would have been a good day !

Lookout · Post by **Lookout** » Sat Sep 06, 2008 6:27 am

I suppose you could do some damage to the bands, but you have to remember the trany works by an oil pump, not a direct mechanical connection. The greater danger (although I wouldnt shift at wot, just seems dangerous) would be for someone to drop them into neutral. by suddenly removing the load from the engine, the resulting overspeed could cause the engine to fail very dramatically.

rickalan35 · Post by **rickalan35** » Sat Sep 06, 2008 8:59 am

Obaby, this is a good topic to bring up as I have often wondered about it.

My Tricabin has the same problem and I just by force of habit, reach over with my right hand and protect the shifter when any of my guests are coming up the steps from the salon to the cockpit.

Of course, in my case with the Tricabin, we're talking about Walter V-Drive Transmissions. I don't believe that they are oil driven like velvets.

Any comments from anyone here regarding what would happen if a Walter V-Drive transmssion was popped out at high rpms??? Thanks

jwrape · Post by **jwrape** » Sat Sep 06, 2008 9:39 am

I would say if there is that much danger of them being hit then you need to fabricate something to protect them from the entryway. I wouldn't risk it. Not even thinking of the damage to the trans but the damage to your crew and friends when they get slammed forward or off the boat or if your boat goes out of control due to hitting just one of the levers at WOT.

rickalan35 · Post by **rickalan35** » Sun Sep 07, 2008 9:58 am

JW - If you're referring to me here, then I have agree with your point about the solution being a change in the shifter control arm but unfortunately, with the way that the hatch is manufactured and positioned and also the manner in which the shifter is situated - it would be NO easy thing to make a change. Other Tricabin owners on here will no doubt agree. I believe that in the later years, Trojan made a change in the Tricabin controls, probably due to this situation.

As well, what is this WOT thing. Does anyone really ride around with these boats "pinned"?? Doubtful. I seldom get over 1800 rpm.

Lookout · Post by **Lookout** » Mon Sep 08, 2008 5:24 am

I think wot is just a referance to worst case senario, I have slammed to wot just once and that was to get in with a customer having a heart attack. the fact is you dont have to be at wot to damage an engine by shifting into neutral and droping the load off the engine. the senario of popping just one side into reverse at crusing speed is something I hadnt thought of, and yes, would probably be very bad. something you chuckle thinking about but would never want to actually happen...the question actually is... how often does it actually happen. Ive had problems with kids in the cabin "driving" while im in the flybridge, and while it does give you a second of "WTF?" you figure it out quickly. as far as pinning the controls in a foward position, you could argue that could be a safety issue but at the same time I cant remember a single use of trany controls that couldnt have waited till a pin or locking device was dis-engaged. one could argue that if it was really an issue, then manufactures would have modified the controls. I know people that have damaged engines by pulling the controls into neutral, but any other senario, Ive never heard of.
That statement being made, im sure itll happen to me any day now.

wowzer52 · Post by **wowzer52** » Mon Sep 08, 2008 10:48 am

I bent pushrods that way one time. made a really ugly sound. I was drunk being funny and really impressed my friends.