tunnel drive

[boston_jake01]

I have never heard of this I am looking at buying a boat with a tunnel drive, what should I know about this? it's on a 23 foot cabin cruiser. please give me as much info as possible.
Thanks
Rich

 

[Frank Acampora]

Re: tunnel drive

I think Penn Yann boats had them quite a few years ago. This is used on a relatively large boat with a shaft drive. It is not I/O so the shaft drive is a bit simpler, however, it is less maneuverable

The bottom of a deep vee hull is inverted into a tapered "tunnel" around 6 feet long or so. Advantages are a more horizontal propellor shaft, and a decreased draft because the prop is about 2/3 enclosed in the tunnel. Prop is also protected somewhat. Since it is enclosed by the tunnel, it also is a bit more efficient.

You don't see too many of them around, so there must also be some deficiencies.

 

[JCF350]

Re: tunnel drive

[SIZE=-1]Definitely built a little different. I can remember seeing only Chrysler engines in them and a cast aluminum oil pan that was about 3/8" thick.
Any way here a website.

pennyanbbs.org/

[/SIZE]

 

[seven up]

Re: tunnel drive

SeaRay is one company that uses them, today. The tunnels offer increaed protection of the prop and shaft from debris and the benefit of less draft as mentioned earlier. Gossip is that they can be the lesser meneuverable in tight situations compared to open shafts and props.


Enjoy

 

[Bondo]

Re: tunnel drive

Ayuh,....

If you want a boat that you Can't turn,+ $uck$ Ga$ like there's No Tomorrow,.....

Go ahead,+ buy it......

Otherwise,...... Keep Lookin'..........

 

[boston_jake01]

Re: tunnel drive

thanks very much for this info I was also looking at a boat with twin engs but it sank at the dock should I stay clear of this too. it is a inboard. I am a mechanic or was a while ago I am looking fo a project but don't want to have a boat thats not worth my time.