TOPIC: A little help please....

I am running a Mark 58 on a 12' Molded Plywood runabout. It gives me an amazing ride, but I can't keep it from bouncing.

Many years ago, I had a Yellow Jacket that had two pads that gave it a smooth ride and stopped the bouncing. They were about 12" long and 8" wide and tapered from zero at the front to about 3/8" at the rear. and were mounted with the thick end at the transom.

Does anyone know if anything like these pads are still available?

If not, any ideas on how to stop the bouncing?

Beautiful boat! Not sure about those trim tabs but could be that your motor is too long for your transom. Can you tae a pic of it and post and we can help from there. There are others much smarter than me that can probably tell you right off the bat. I'm surmising at this point.

Bob

Sounds like cedar shakes. My wood boats had some mounted to the bottom of the boat. Haven't seen any rubber or plastic ones ?

if the hull has a rocker in the bottom (opposite of a hook in the bottom) that will cause porpoising. Also if your motor is tilted too much to drive the bow upward that will also cause it. If you are over powered with a 45 HP motor on a 12 foot boat that could also cause it. You could try to add a plane to the stern to correct it but be careful you do not end up stuffing the bow with all that horse power. Check the bottom 1st to be sure you are not bulging anywhere (convex if hooked) then try lowering the tilt of the motor by 1 position to see if that stops it. Instead of using a set of shingles I would use a set of adjustable tabs that can be attached to the transom and adjusted with a screw.

The Items that you are talking were installed at the factory. I just remade some on one of the Yellow Jackets that I am restoring. Give me time tomorrow and I will get some Photos...I just got back from a 360 drive after being on an out town job and I do not feel like getting up from this chair..

Motor is correct length, short shaft I'll add picture if I can

I run this with tilt pin in first hole, using a 12" cupped bronze prop. In a slight chop, it will hit 39.6 on the GPS. Transom height is 15 1/2, but I have blocked the engine up to 16 3/4".
Just picked up a 14" prop which I haven't run yet.

Thanks for input...hopefully something will work. BTW, the 12 Yellow Jacket was rated for 50HP and this is the same hull.

Picture from rear...picture won't load for some reason

Roger that on the height. Ok if your all the way at the bottom tilt wise, then definitely double check your bottom as Jim said. Sounds like your going to need to install those shingles.

Bob

forgive my ignorance if i'm wrong, but these sounded like what you were talking about...

spokane.craigslist.org/for/2923576426.html

also, the person listing the ad said they were too big for his 12' boat. i wasn't sure if they could be modified or not. figured it was worth a look at least.

They do seem to be too big for a 12' boat. As I recall, the "shingles" on my old boats were only about 12" long and 8" wide: about 3/8" at the thickest point.

well, now that i know what they're at least called and the size you're looking for, i'll keep 'em in mind in my late night CL trollings... sorry i couldn't help