qustions about old boat

[severn don]

Good day all. We have had an old boat hanging in the boat house for about twenty years that the brother in law was given. I decided to get it down and try to bring it back to life. It is an 1960s Hummber ltd model trillium with a 1970 60 hp Johnson with 70 hp carbs on it. I took a week to revive the motor and strip and check and clean every thing it was only running on two carbs and after checking it was not getting spark to the top carb. After replacing that coil, it still did not work. Eventually I found it was a loose wire under the flywheel. I then did a I gallon of gas to a bottle of sea foam. Wow does the motor ever sound good and the crud that came out of it was amazing. So I took it out on the water and slowly opened it out, then I hit it full tilt. The boat suddenly took off and violently turned left throwing me out of my seat and the steering wheel out of my hands and was turning a tight circle left me thing the boat was going to tip over. I had to use my leg to reach the throttle to turn the throttle off. So I noticed that I cant do that now. Now when a wave hits the bow the boat can suddenly turn left or right and when I give it power it can seem to plow nose down a bit. There is a bracket on the transom on the left side with a 4 inch block of flat wood there the bracket is adjustable. I do not know what it is used for, but it looks like this would be to stabilize the boat if I am in the boat by my self. If I have people in the back bench seat it appears to be pretty stable but I do not know. Now I can fix most motors and such and have only ever had an old steel boat with a 25 hp on it. So this is all new to me and any advice and suggestions are really appreciated. I would really like to restore every thing proper if I can.
All the best Don

[rick_iles]

Does the motor actually turn, or is it still straight when it takes off left or right
Check the lower unit. There should be a fin attached to the cavitation plate, just in front of the prop. See if that fun is secure and not loose...
The bow down issue sounds like a trim issue. If the lower unit is trimmed down towards the transom, that will push the bow down.

[severn don]

rick-iles when I did the acrobats out of the seat I do not know if the motor was turning. but when I am in control the waves hit the bow then it shoves you left or right with out turning the motor

[GYPSEE]

rick-iles when I did the acrobats out of the seat I do not know if the motor was turning. but when I am in control the waves hit the bow then it shoves you left or right with out turning the motor

It sounds like your trim is way too low and the boat is plowing.

Here is a video explaining trim

https://youtu.be/FxSIhhXE1Aw

If your motor is only manual trim, what I do is try every trim hole from bottom to top, once it starts porpoising, drop it down one hole... don't drop the rod!


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[Bushmoose]

I'm thinking it's perhaps a trim tab issue? Can you post a few pics?

[severn don]

yes guys Thank you will look into that when I get up north again and post photos when I get home tonight. As always I thank you all
Don

[sawbill]

Its definitely a trim problem. I restored an older 14 ft deep and wide aluminum boat that was probably rated for something like a 25 hp. I experienced everything you have, right down to being tossed off the seat onto the floor when the bow dove down into a wave. At first try, I couldn't get my 9.9 Yamaha over 1/4 throttle before the boat started to plow. Backing the motors trim all the way out accomplished very little and that was with every ounce of weight possible moved rearward. I ended up making a wedge for the transom that would tilt my motor even further out and that helped somewhat. Even as it sits now, I still have to have my passenger sit on the back seat with me in order to get the motor up to speed and have the boat plane safely. (He has explicit instructions to discretely slide up to the middle seat if we see another boat on the lake but I have to back off the throttle.) Anyway, good luck with your project boat.

[severn don]

Thanks saw bill that is what is going on even though the boat says it is rated for 85 hp

[Bushmoose]

I still have to have my passenger sit on the back seat with me in order to get the motor up to speed and have the boat plane safely. (He has explicit instructions to discretely slide up to the middle seat if we see another boat on the lake but I have to back off the throttle.) Anyway, good luck with your project boat.

I think I saw you guys out on the lake one day? Looked pretty cozy so I didn't want to disturb you.

[sawbill]

BM, I figured I'd hear from you sooner than later. I liked it much better when you were hounding GW about his wood pile.