New to inboards

Speakrdude

Ensign
Joined
Feb 25, 2004
Messages
942
Well, Looks like my next project boat will be an 88 model Sea Ray 300 WE. It has twin inboard Merc. 5.7's. I am new to whole inboard idea so can anybody enlighten me to what kind of trannys (V-drives?) or anything else that may apply to inboards.

I have spent countless hours training Don S. on trailering techniques and other important stuff with I/O's but not much experience with the whole shaft, prop, rudder thing. It also has a Westerbek genny on board.

Thanks to all.

Jim
 
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Don S

Honorary Moderator Emeritus
Joined
Aug 31, 2004
Messages
62,321
Re: New to inboards

I have spent countless hours training Don S. on trailering techniques

"Dude, your boat is on the trailer backwards"

LOL, I remember that thead well, and it wasn't even on this forum ;)

Head up to the Adults Only sticky at the top of the forum and look for the service manual for your engines SN. Being an 88 it could be an 89, 2 different manuals. Get your serial number and find the right manual, there are sections in them for the inboards and the different transmissions.

One question though, didn't you get enought abuse from your previous boat rebuild?
 

arks

Lieutenant Commander
Joined
Nov 7, 2002
Messages
1,929
Re: New to inboards

V Drive transmissions are available from a few manufacturers. The most popular are Paragon and Borg Warners' Velvet Drive. Their primary benefit is to allow the engine to be placed near the stern of the boat, allowing the builder to maximize interior living volume. Often the V Drive's shaft packing can be extremely difficult to service because if it's location directly beneath the engine.

Here's some info cut and pasted from various sources:


Paragon:
ParagonVDrive.jpg


Velvet Drive:
VELVET DRIVE 71 - 72 V-DRIVE
Borg-Warner's integral V-Drive marine transmission is a compact, self-contained unit that helps create extra cargo and cabin space by allowing you to move your engines further aft. Because the V-Drive requires no universal joints, a potentially costly maintenance item is completely eliminated. The deeper offset of the Velvet Drive? V-Drive marine gear allows easy propeller shaft alignment for quick, simple installation. A series of reduction ratios is available. For twin-screw applications, opposite propeller rotation can be provided for two engines of like rotation through the use of gear and chain drive transmissions.
Cutaway:
borg_warner-vdrive-cutaway.jpg


Random thoughts about inboard power:
Shifting will be smoother with inboards.
Less maintenance compared to I/O's
From my experience, inboards are typically more responsive (than equivelent I/O's) during low speed manuevering due to their propellers being located closer to the boats' pivot point. OTOH, inboard rudders are usually NOT very effective at low speeds because they require waterflow over their surface to work. Most competent captains will not turn the wheel, but use the transmissions and/or throttles to control the boat around the docks.

The packings (shaft and rudder) are typicallly flax, sometimes impregnated with teflon. These should be adjusted to minimize water entry, but properly adjusted flax packings SHOULD allow a miniscule amount of seepage to lubricate the shaft (roughly 1 drop per minute). The newer GFO packing is completely self-lubricating, so they should be adjusted to the point where NO water enters the hull.

The strut bearings (supporting the shaft below the hull) are lubricated by water and not adjustable. If they are holding the shaft without allowing lateral movement, they are OK.

Obviously, inboards are not trimmable or tiltable so extra care must be taken operating in shallow water.
 

Speakrdude

Ensign
Joined
Feb 25, 2004
Messages
942
Re: New to inboards

Actually Don, I am in the middle of restoring my second 1984 2750. Labor of love, I suppose. I really appreciate all your help. That was an experience pulling that 28' boat on an 18' (P.O.S.) trailer all the way from Tampa to West Palm Beach. Hopefully, I will be better prepared (with my own trailer) this time.

Jim
 

Don S

Honorary Moderator Emeritus
Joined
Aug 31, 2004
Messages
62,321
Re: New to inboards

Hopefully, I will be better prepared (with my own trailer) this time.

You have to be better prepared, no way in ell could it be worse than the blue bomber on the trailer backwards.

Get some pictures or SN's if you can. It's easy after that.
 
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