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Folks... I am interested in how your motor is trimmed for a similar sized boat and motor...

I have a 15' 10" 1960 Seacoaster... with a 75HP 1961 Johnson....

There are four holes on the bracket that mounts to my transom. I currently have the peg/rod through the second hole from the last... that is the third from the transom.

Although it seems to run well and level, the ride seems a little hard, and I am wondering if am running too heavy on the bow... I feel the chop right at my feet when buzzing along. Top speed is about 32 MPH... the boat handles well, but I think others get a higher top speed.

I would appreciate hearing what others with a close combination of Thompson/75OMC have their motors set at.

Thanks.

John,
I have the very same boat as you do, but with a 50hp '58 Evinrude. My pin is in the same location; 3rd hole out. With 3 people in the boat, (maybe a total of 460lbs) mine registered 28mph and was level and very stable on plane. When I hit a wake at speed I also felt a hard slam under my feet but otherwise, it seems very smooth. Perhaps, with the extra weight I had, my bow was a tad higher than yours.
It would be interesting to hear from more owners of similar set-ups. Maybe the best thing would be to just try a different hole and see what results you get.
Verne

Play around with different settings. The closer the pin is to the transom, the more the bow will be up.

I move things around all the time depending upon how much weight in the boat (people, coolers, anchors, rocks...) or if it's just me alone.

Just don't drop the pin - it doesn't float!!!

Andreas

Andreas,

The closer the pin is to the transom will cause the bow to drop not to rise. As you move the pin away from the transom moving the motor leg farther from the transom it will push the bow up.

If you are at full plane you are going to feel more of the slap of the waves and wakes against the bottom of the hull. When the boat is up on plane it is not cutting thru the water as much as it is gliding ontop of the water. This will cause you to feel more jaring when on rough water.

You mainly want the boat to be level or reasonably close to level when at full speed. If the bow is up then you need to drop the pin closer to the transom. If the bow is plowing then you need to move the pin away from the transom. Sometime you have to jsut pick the location that is best for most of the time running. If you have a motor with veriable electric or hydrulic operated trim on the motor you can change on the fly and have infinate adjustment. With the older motors with only the oin adjustment you do the best you can with want you have.

Good Luck,

Phill

I have a 1960 Cruiser's Inc 202 16' , running either a 1960 75 Evinrude or a 1960 40.

The different in top speed between first and last pin is probably at least 5mph. The bottom pin is used to keep the bow down in really rough water, or max take off for sking. It could cause bow steer, something you don't want. The first or second pin is also used if all your weight is in the rear. The 4 pin will normally be best for top speed and economy, but when the water gets rough, time to stop raise engine and move pin lower, unless things are really rough pin 2 from the bottom should do.

Newer engines have power trim which allows lowering or raising engine under full power.

Top speed of mine with 75 is better than 38/39 with just me and has run 41.3 without windshield, with a 12' bronze prop and 4th pin. Opening starting rope door adds 1/2 mph.

Image of 16' Cruiser's running 41.3 gps with 1960 75 Evinrude

http://www.aerialimaging.net/johnpics35

Thanks Folks... I appreciate the comments... I think I will need to experiment a little the next time I am out... I usually have two people @ about 310 lbs in the front seat, and 10-15 gals of fuel in the rear.

I don't want to switch, but I think I would rather that the boat had a smaller, lighter motor, that may have less strain on the transom... Although, I think I have torture tested mine enough with a few dumb things plus going too fast in some rough water, to know that it isn't going to rip the transom off anytime soon.

I remembered John and the mileage logs... 41 MPH w/o a windshield, wearing a swimming cap, both hands in pocket, and not eating breakfast... (just kidding... I think it is great)..

John... when you say bottom pin and 4th pin, which do you consider the pin nearest the transom, that keeps the prop lower in the water? Bottom pin = closest to transom= Pin 1, right?

I have 2 props.. 10 1/4 by 10 and 10 x 12... I don't have the original 10x 11... I don't see much difference between the two I have. I have tons more RPMs left, so I would get a more aggressive prop, if I knew how to get one for the old motor... much bigger dia will hit the cavitation plate..

John H

Pin#1 is closest to transom.

You could get a 12 pitch 3 blade in bronze and have it cupped, Then get the adjustable transom brackets from an OMC, the have the same hole pattern as the ones we have, then you could raise the engine up as much as 2", good for about 2 mph.

Props are available from Evinrude, very common. Cupping would give you an extra 2". Don't think you need it. 12" is plenty big. Cupping would allow more trimand higher transom height good for several mph.

You noticed, my hood was up on my jacket, that's because it was in the dead on Winter, and it was only 50 degrees. If temperatures were in the thirties then I might pick up a 1/2 mph. Salt water or water temperature of 33 could also help performance maybe another 1/2 mph!! You guys up north are so lucky, so easy to find cold weather for max performance!!!

For every day use, my boat is a user boat, I prefer my 1960 Evinrude 40 Lark II. Gets 25/30 miles a 6 gal tank, vs 13/16 with the 75. With the 40 and 12 pitch top is 25 and cruises very well at 15/20.

Ideal motor would be 25 to 40 4 stroke. I do own a 2006 Merc 25 4 stroke, it's gets 17/19 mpg vs 7 or so with my 1960 Evinrude 40 on the same 16/ alum jon boat. Merc is 1 1/2 mph faster. Merc weights almost 25# more than my 1960 Evinrude 40. Guess 16' Cruisers would get about 10/15m mpg with my 25 4 stroke and it would be almost silent..

I have a 1962 202 with a 75 HP Evinrude on it. I had it in the second hole and the boat did not perform very well. It rode ruff and handle terrible. I moved it to the third hole and got the nose up a bit and it handled like a compltely different boat. It goes about 38 mph with a 17 pitch prop on it.

Michael

Is your 75 a 3 cylinder? A 3 cylinder would use a 17" prop, great engine gets about twice the mpg as my old 4 cylinder 75. Gear cases are completely different.

If your boat handles poorly in the second pin, could be an indication of a hook in the bottom.

John. It's a three cylinder 1975 75 HP. It doesn't have a hog in it, just runs better in the third hole. I'm not sure of the prop diameter but I'm sure it's not 17 progably more like 15 1/2 with a seveteen pitch. I'm going to be adding power trim to this boat as soon as I can find a decent deal on one. Mike

Dead of winter and only 50 degrees. I wish!!! We have hard water during the winter, i.e. ice. The only boating that takes place is ice boating!

Andreas