Help 35 Horse Chrysler Outboard Problem

I have an older 35 horse Chrysler. It starts great and runs great at very low speed but when I give it the gas it sounds like the prop is spinning in air or clutch slipping or something. Someone told me it's not worth fixing but don't know if they were being honest with me. Can it be fixed reasonably or can I get another another lower unit at a reasonable price? I am new to the boating world. Thanks.

Re: Help 35 Horse Chrysler Outboard Problem

What is the shaft length of the engine and what is the depth of your transom? Do they match?

Re: Help 35 Horse Chrysler Outboard Problem

OK, I'm a dummy but I assume you mean the transom is the very bottom of the boat.

The flat plate above the prop is about 4 inched below the bottom of boat. so I don't think the prop is actually coming out of the water.

I put a picture of the motor/boat in this post. I can tell you it is a long shaft.

Someone told me there is a rubber boot or whatever that could be chewed up but I see no boot. When I got the boat it had no shear pin in it and thought that would be the problem. I did replace it but again I can only go in slow speed. The splines in it see to be OK from hat I can tell by looking at it.

Thanks for your help.

Re: Help 35 Horse Chrysler Outboard Problem

One problem you have is you have a long shaft motor on a short shaft boat. The plate you mentioned is called an anti ventilation or anti cavitation plate and it should be even with the very bottom of the hull. I can see from the pic that this plate is at least 4 inches lower then the bottom of the boat. In order to convert this motor you would need a smaller water tube a smaller drive shaft and then you would just have to take off the extension between the lower unit and the motor leg.

You could test for a spun prop. draw a line with permanent marker between the prop cone and the prop. When motor over revs or slips check the line and see if it still lines up. If not prop is shot and will either have to be repaired or replaced.

Re: Help 35 Horse Chrysler Outboard Problem

Thanks for the response. I like the idea for checking the prop spin and will check it out. My son says the motor is OK but the way I took the picture skewed it so it looks too long. I will try the prop spin test tomorrow. Thanks.

Re: Help 35 Horse Chrysler Outboard Problem

Even given the angle of the photo, the engine still looks like it is sitting too deep in the water---The long shaft insert is 5 inches and it appears that the anti-ventilation plate is sitting about 2-3 inches below the hull bottom. Therefore the transom is a long shaft transom but a bit short--like maybe 18 inches deep instead of the usual 20. That happened a lot on older boats. but that's not your problem

Check the prop hub for a spun hub. If it is spun, the rubber donut inside is deteriorating and it will happen at progressivly slower speeds.

Your local marina or boat dealer can send it out to a prop shop for re-hubbing. When I had my first Chrysler, re-hubbing cost 5 bucks. Now it's probably about 35. Back then, a Michigan bronze two blade racing prop for that engine cost 25 bucks.

At any rate, You may be able to pick up a used prop on the auctions for that price. Your prop is a stock prop made by Columbian props. Usually the size was stamped into one blade at the root. It will be something like 10 3/8 X 12 1/2. There will also be a number under the tailcone like A 293265. This is a 10 3/8 diameter by 12 1/2 pitch aluminum prop. Even if you do get your prop re-hubbed, it is still good insurance to have a spare on board.

Once you get the engine and prop running correctly, then try raising it on the transom until the anti-ventilation plate--also known as the cavitation plate-- is even with the bottom of the hull when the plate is parallel to the bottom. A straight piece of wood held against the plate helps to measure.
Raising the engine is free and can result in gains from 2-5 MPH.

Re: Help 35 Horse Chrysler Outboard Problem

Thanks for the great info Frank. How do I check the prop to see if the hub is spun? I suspect from your note (and others) that the hub is the main problem. In any case I am going to have it checked out and fixed. I like the advice about having a spare prop and will look for one although I have not had much luck in finding one at a reasonable cost ($160). I have the winter to hopefully come up with a spare. I did find a website that would fix it for about $32 plus $10 shipping and of course I would have to pay to get it shipped there. I will try to find a local place that might do it (Rochester NY) to save shipping costs.

I roughly measured the C plate and it appears to be about 3 1/2 inches from the bottom of the boat.

Thanks again.