Inboard motor - rotation change?

[62 woodie]

Im in the process of looking for a "newer" V8 for a 62 Higgins inboard. The motor in it now is a Graymarine 135 , RH rotation.

This boat is a little different in that it steers from the left side. I found a complete (tranny ,etc) Chris Craft ,283 Chevy-185hp, LH rotation.

My question is ... would there be any major problems , steering-handling-etc, changing from a RH to a LH rotation if I also changed to a LH prop? (Ive also located a used 12 x 14 LH prop.. it now has a 12-12 RH.... The boat is 17 ft)

I was under the impression that one of the main reasons for a RH rotation is to "offset" the drivers weight in a "standard" RH steer.

Any thoughts / potential problems? Thanks! Steve :confused:

[ 10-22-2003, 01:12 AM: Message edited by: 62 woodie ]

[imported_Conrad]

I've had both RH and LH motors in a variety of RH steer boats, all under 22', a variety of new and old designs/builders, and can't say that I ever really noticed a big difference. All were used for skiing. I think any effect would be most noticed in a narrow, deep-V hull. Most of mine have been flat bottomed and a bit beamier to flatten the wake.

As we usually boat with friends, there always seem to be enough bodies to put the weight where it needs to be. Failing that, if it really bothered you, one could always add a transom wedge or trim planes.

[nedL]

It used to be standard (& is now for the most part) to put a right hand rotation engine in a single screw boat, but I have noticed a lot of new boats (from small ski-boats like Correct Craft up to 45' 'trawler' types) that have left hand props on them. I believe the only thing that will differ will be the way she walks when first put in reverse.

[High C]

Originally posted by nedL:
I believe the only thing that will differ will be the way she walks when first put in reverse.I think this is about the only difference you'll notice. She'll back well to one side, but not as well to the other.

[brad9798]

Like NedL said, and High C confirms ... that is the ONLY difference you will notice handling wise.

Depending on the size/weight of original vs. the 'new' 283, you may notice acceleration differences ...

Can't go wrong with 283 blocks ... mine twins are nearly 40 years old ... ALL original, no rebuilds ever, and they still have great compression at 1900 original hours.

Part are as simple as the autoparts store for most fixes ...

Go for it.

Brad

[Jack Heinlen]

What the others said, and adding you will also notice the difference going forward, particularly at slow speeds. I'm a decent handler of a single screw inboard, but always was amazed by the mechanic at the marina where we used to store our boat. He was an artist. After his work for the spring splash he'd take a boat for a spin. A quick hand to the throttle can kick the stern an amazing amount. He could park a boat in a space not a whole lot longer than it's length in less time than it takes to write this sentence. His high speed approaches were a bit hair-raising until you got used to them, and probably a bit irresponsible with other people's boats(what if that freshly tuned engine stalled?) but I never heard of Dick scratching a boat.

It's actually a stronger seeming effect in fwd than in reverse, because in reverse you don't have the wash on the rudder.

[ 10-22-2003, 05:30 PM: Message edited by: Jack Heinlen ]

[62 woodie]

Thanks for the input! Ive only had the boat on the water once and its got a "mind of its own" when in reverse already! Also noticed in forward it turned better one way than the other. ( I think RT), but was I was also having problems at that time getting the boat to plane.

Prop options are completely new to me. Does anyone know how many different prop mounts there are? ie shaft dia , keyed vs splined etc? My boat currently has a 12"-12RH. I found a 12"-14 LH , with the added 50hp , can I use the extra pitch? (its a 17' boat)

[nedL]

For inboards there is realy only one 'prop mount' used. that is a tapered shaft with a square keyway. I'll almost guarantee you have a 1" shaft (the taper is always std). You may well be able to use a 12x14 prop. The only problem with using to 'large' a prop (dia. or pitch) is that the engine will not hit it's rated RPM. Also a prop shop should be able to change the pitch 1" in either direction for you (or that used to be the std rule of thumb.) You might also look at going up to a 13" prop. You should check to make sure that you will be maintaining at least 1 1/2" or so clearance between the blade tip & the bottom of the boat.

[merc412]

To change rotational direction from one to the other requires replacing the camshaft, distributor and possibly the water pump.

[Jack Heinlen]

Are you sure you want to change motors? Why? Speed?

But back to handling. If you have a place where you can set up a simple course consisting of bouys made from bleach bottles--simple, just a half dozen in a rectangle, anchored in shallow water--practice a variety of maneuvers. Get a feel for how the boat moves with different amounts of throttle, and in different turning situations, backing, forward, etc. Play with it, over and over. Plastic bottles are much more forgiving than pilings, or other boats.

People on shore who don't know will think you're nuts, but who cares? Those with a brain will think you're pretty smart to learn how your boat handles.