Chrysler prop question

A semi complicated question, at least to me. I installed a Chrysler outboard on my '84 1600 Bayliner cuddy. It had no motor when I got it.
I had a motor which was a 1977 Chrysler 65hp magnapower II. The motor has had a powerhead change to a 55hp Magnapower II. So it is essentially a 55hp mated to a 65hp lower unit. It runs excellent. It is underpowered for the boat which I knew would be the case but it is a bit more underpowered than I thought. It doesn't quite get the boat on a decent plane. I use it only for lake fishing but I would still like it to plane. It has the factory aluminum prop stamped 493 13. The prop is 9" diameter. And I assume it's a 13 pitch?? Is there an alternative prop that will give me a bit more top end? I'm not even sure this is the correct prop for this engine. It seems a bit small in diameter. I measured from the center to the outside of one blade and multiplied by 2 to get 9".

Re: Chrysler prop question

that diameter seems small - maybe an 11 pitch will get you on plane. here is one on the site that MIGHT work for you: 11-1/2” Pitch Chrysler Outboard Boat Propellers 55 HP 1966 - 1983 - iboats But then again you said yours is 65 hp - i don't see that model on the site. Check ebay.

but I think Frank will be your go to guy, I bet he will post about what you need.

Re: Chrysler prop question

I agree Frank will get you straightened out. The 35-55 motors are in the same section in my generic manual.
The 65 is in a different section covering a different 55,60 and 65 motor.
At any rate there is a good bet that the 65 gear case is a different ratio.
You can check the ratio if you have the parts turn the driveshaft and count the rotations in relation to one rotation of the prop.
On the motor pull the plugs rotate the flywheel and count the rotations.Probably something like 1.75- 1.85.Just guessing.
Will require some careful measuring to tell the difference.
It does seem a healthy 55 could plane a 16' cuddy. Unless some outside influence is interfering.

Re: Chrysler prop question

Well, srukke: Your question is a bit more complicated than you think. You see, Chrysler made that twin carb series of engines with two different lower units depending upon year. Earlier ones used what looked like the same prop as the single carb versions of 35,45,55 engines. The prop appeared to be spline drive with a thrust pin held under the tailcone.

Later ones used a newer lower unit with a larger drive and prop shaft and different splines. The prop was spline drive with a thrust washer just like Mercs and OMC.

The problem is that while I have seen the earlier models, I have never worked on one and can not give you a definite answer.

Send Nordin a private message and if he can't help you, try Franz at franzmarine@aol.com. This guy knows just about everything and has just about any Chrysler part you might need.

Re: Chrysler prop question

Thank you everyone for the info.