New to the forum with my first question bout motor mount hight.

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I am the new owner of a 2000 208 Grady White with a EFI 225 Saltwater Yamaha. The boat slightly used and was rigged by a dealer in Wisconsin 25 years ago. The owner that I purchased it from used it for a taxi to go to and from a cabin on an island in Green Bay. Super clean boat and rub=ns great. After I purchased it I started doing some service work to the engine. Knowing that one of the weak areas of the older Gradys was the transom to top deck sealing. When I was inspecting the sealing area I noticed the motor is mounted in the #1 hole. Seems low to me. I would suspect the motor should be mounted in hole 2 or 3 with a big gear case 225Hp Yamaha. I'm looking for input as to what hole others 208 Grady owners have the motor mounted in? Thank you in advance for any information provided.
Brian
PORT-A-GEE
Gold Looper
208 Grady
 
Gearcase size is not important. Besides, that gearcase is not different than all the rest. It's really all about the anti-ventilation plate compared to the hull bottom. There are tons and tons of threads about this - if you wanted to read up on it you can search. There's also tons and tons and tons of threads about this on the internet and it's all basically the same - the specifc hull is typically of no consequence unless it's an oddball hull design, which the Grady is not.

The anti-vent plate, roughly speaking, should be level to slightly higher than the hull bottom. Check that and report back.

But... how does it run? Can you get max RPM (or close)?

If it's lower than the hull bottom - go ahead and move it up and experiment to see what works best for you.
 
DennisG01 said:
Gearcase size is not important. Besides, that gearcase is not different than all the rest. It's really all about the anti-ventilation plate compared to the hull bottom. There are tons and tons of threads about this - if you wanted to read up on it you can search. There's also tons and tons and tons of threads about this on the internet and it's all basically the same - the specifc hull is typically of no consequence unless it's an oddball hull design, which the Grady is not.

The anti-vent plate, roughly speaking, should be level to slightly higher than the hull bottom. Check that and report back.

But... how does it run? Can you get max RPM (or close)?

If it's lower than the hull bottom - go ahead and move it up and experiment to see what works best for you.
Click to expand...
Thank you for your post. I agree with all said. This is not a new concept for me. I owned and operated a small marine service shop in the midwest and if I have rigged one outboard I have rigged a hundred. I was a certified Mercury marine and OMC service technician and rigged outboards for a number of years. Many performance bass boats but also Bluewater boats Whalers, Hydrosport, Aquasport, Stratos, all similar to Grady's with 25" transoms and larger HP 2 stroke motors ( 80's 90's and early 2000 boats and outboards. Yes there trial and error to find the sweet spot on best mounting hole and matching a prop that would keep the motor hooked up. Once that is found it is a repetitive install if hull and motor are of like kind. I always used the rule of thumb that starting position (cavitation plate) 1" above the centerline of the hull bottom on a V-hull or 1" above the pad if the hull had a stern pad. Then I would work up a hole at time and compare performance and see if the prop starts to blow out at a given speed or on a turn. On Bass boats I would live with some blowout because of performance gains. On blue water boats I would not because of the rougher sea conditions the boats would be operated in.

I can do this with my new to me 2000, 208 Grady that has been operated on the water for 25 years mounted in the # 1 hole with cavitation plate slightly lower than the center line bottom. It was rigged by a Grady White dealer in Wisconsin that I am familiar with because I purchased a Boston Whaler from them in 2002 and the had the motor mounted in the #1 Hole too. Boston Whaler recommended #2 hole in their rigging instructions. I placed it in the #3 hole and had better hole shot and picked up an additional 1mph between #2 hole and #3 hole. 3mph increase from #1 to #3. That is free speed ! I remember this because of the discussion I had with the dealer!

My main reason for posting this thread is to try to skip the experimental work. The boat is 25 years old and there are a lot of 208 Gradys out on the water. I figured that the experimental work has been done. There are many Grady owners that have found the sweet spot and I was posting this to find it. Best hole mount while I have the motor hanging when I am inspecting and resealing the bang plate.

If you own a 208 with a 200 or 225 hp what mounting hole are you running in?

Brian
Gold Looper
2000 Grady 208
 
"Experimental" line of thinking - understood. What you're REALLY looking for here is someone that has TRIED both/multiple holes to see the difference. Not someone who says "I have it in X hole and it works great".

FYI... anti VENTILATION plate, not cavitation. Look up the definitions - they're two entirely different things. :) :)
 
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