How Fast ?

[Brymill]

Hi guys,

I've got a 13'6" wooden runabout a 1956 30hp Evinrude. I converted the motor over to a short shaft last week and well I ran the boat and by my GPS it will only run about 21-22 mph. With the motor as a long shaft it ran about 18-19 mph. The boat probablly weighs less than 300 lbs. I have not been able to adjust the high speed as well as I would like at WOT due to lack of having someone ride in the boat with me. The motor has new coils,points,condenser, and it has a new fuel pump to convert to a single line fuel tank. Motor runs quite well. Any ideas on what kind of speed to expect? I was thinking in more of the 30-35 mph range or am I expecting to much? I am attaching a photo of the boat on its maiden voyage. I also want to say thank you for those who have helped me get it this far.

Bryan

 

[Fromtoronto]

Re: How Fast ?

wow.. 22 mph on a 30 hp? thats good... I have a 110 hp on back of a small 15 foot bowrider, light boat actually but only doing 38 mph...

 

[CATransplant]

Re: How Fast ?

Yeah, that 30 hp should push your little boat up around 30 mph or more with no problems.

So...I doubt you have a tachometer for that engine. It would be nice. Tiny Tach has one that will work.

What prop is on your old 30 hp? You may be able to up the pitch a bit and still turn max rpms. Props are available from 10" pitch to 13" pitch. With your light boat, I'd guess you could turn a 13" pretty well. Lots of cheap old props for that motor on ebay all the time. You might even find a brass or bronze one. It will bite a little harder and might speed things up a little.

Have you experimented with trim position? Tilting the outboard away from the transom will tend to raise the bow, increasing speed by having less of the boat in the water. There's a sweet spot position, one hole in from the one that makes the boat porpoise. In the photo, it looks like you have the outboard tilted in at its maximum.

Experiment. Let us know what you find.

 

[jbjennings]

Re: How Fast ?

My '54 25hp bigtwin only pushes my LIGHT 15'42" aluminum boat with only one back seat, and a seat on the nose so it's really light---about 25 mph.

My Dad's brand new yamaha 25hp outboard on a light 14'36 inch bottom only pushes he and I, and no gear inside, exactly 26.3 mph. Considering the 30hp you have was probably rated at the crankshaft and not the prop like the newer yamaha 25hp, I think a crankshaft rated 30hp on your heavier boat will be hard to get up to 30 mph. I'd think around 25mph would be more realistic. I'll bet when you get the high speed circuit set right you will get about 25mph. Then again, I've never run an old 30, so I could be totally wrong!
I love your boat!! MORE PICS!!!!
Just my humble opinion---I know CatTRansplant has a lot more experience than I have!
JBJ​

 

[CATransplant]

Re: How Fast ?

Well, his cute little boat has some really nice lines. It's obviously designed as a go-fast little boat, unlike most tinnies.

If he can turn a 13" pitch prop at the high end of the engine's rated speed, he should make right about 30 mph. Once he gets the trim dialed in on his little speedster, I think he'll see a nice increase from his 22 mph.

The high speed needle adjustment will have to be made, too, and he's going to need a passenger in the boat either driving or making the adjustments. That'll be tricky, since the loading will be different and the weight higher, but...

I suggested the brass or bronze prop for his engine because, like the SS props of today, they flex less than the aluminum props, and will probably bite a little better.

Right now, though, I think it's trim that's keep his speed lower than it should be. I'm betting that trimming out to the next to the last hole will be about optimum for him. Could even be the last hole out, but I don't know.

It's a neat boat, and it should perform very nicely with that 30 hp.

As for the older 25 and the Yammy 25, it is what it is. The old Big Twin is a torquey sort of engine, and should have the oomph to spin a 13" pitch prop to it's recommended max RPM on that boat.

Zoom!

 

[Brymill]

Re: How Fast ?

Thanks for the info guys. I agree that the high speed needs a fine tuning and did give it a try with my wife steering the boat and as I was stepping over to the back of the boat she cut the wheel and darn near threw me out so I decided I would try that again some other time. The prop seems to be the original and I don't know what dia or pitch. I'll have to reasearch that a bit.I did try adjust the tilt on the motor before I converted to a short shaft but have not tried since the conversion. I had way to much motor in the water with the long shaft. I need to give it another try. It plains real quick and lays flat. It rides a little rough (no padded seats) but definetly fun. Its seen more rode miles than on the water. I 've had it in a few boats shows in the area and there was a photo of it in the NC Maritime Museum " Waterline " publication. Its a neat little boat and pobably don't need it to go any faster but I'm one of those guys who dosen't like to say " its not right but good enough ". I want to see it run as best it can. Thanks for your help and suggestions and will definetly give them a try and let you guys know how they turn out. JB I have attached a few pics during the 2 year restoration. thanks for your comments. You guys are always helpful.

 

[R.Johnson]

Re: How Fast ?

That is one nice boat, and a great job of restoring. Is that boat a Pabst by chance, or what make is it? One thing they did back then was to mount the steering on the center deck, and used the front seat for passengers. That would help your performance with one person, but I don't know if you would want to make that change now after all the work you have in it. When I was a kid, we had a 12.5 ft. molded mahogany Dunphy with a 1957, 35 Evinrude mounted that way.

 

[jbjennings]

Re: How Fast ?

After looking at those photos, I'll have to say Cattransplant's right as usual. Actually, I couldn't really believe it was just 300lbs. at first but after seeing it on the trailer...... I can't wait to hear how fast she goes after the high speed adjustment. THat thing should be fun for sure!!!!
I also didn't realize the transom was like that..... very interesting. That boat was definitely built for speed. YOu'll have to post some more full throttle pics when you get it "right" like you want it!!
I look forward to seeing 'em,
JBJ​

 

[Brymill]

Re: How Fast ?

RJohnson - The title on the boat says its a 1957 Meteor - homebuilt - which suggests to me that it is probably a kit boat of some kind. I have searched the web for a long time trying to find information on it with no luck until last week. I found a pic of a boat that looked exactly like it but with controls at the back. They were also looking for information as well. I've been told it is a Chris Craft, Speedliner, James Craft, and all sorts of things. I even bought the Bob Speltz book on outboard boat manufactures and have no luck. As JB mentioned about the transom its a little different and hard to find many boats like that from that time period. I have seen some Larsons similar to it. If anyone has any info I would be greatful to have it. Anyway I hope to try it out again this weekend and will try to post photos and maybe sort video if possible. Thanks

 

[SnappingTurtle]

Re: How Fast ?

I don't know what it is, or how fast it should go, but man that is one sweeeeeet lookin boat!

Please post more photos!

 

[CATransplant]

Re: How Fast ?

Interesting. Chris Craft sold a Meteor kit in the 1950's. You can see a photo of one of the boats at:

http://www.zazzle.com/chris_craft_print-228931544853619231

 

[R.Johnson]

Re: How Fast ?

My first thought was Speed Liner until I looked at the bottom, and transom. That is a classic boat, and one heck of a nice job.

 

[CATransplant]

Re: How Fast ?

You know, looking at those extensions, I'm betting that boat will stand a lot of out trim on that 35hp. Unusual design, though, and it could have been a addition made by the kit builder.

For best speed, a guy'd want not much more than those extensions on the water. Notice the little step at the front of the extensions. Yup...I'd try some serious trimming up of that 30 hp.

 

[Brymill]

Re: How Fast ?

Hi guys, I just wanted to give an update. I have not ran the boat yet but I did find a SS 13 pitch prop made by Powertech. The guy that runs the marina I bought the short shaft from told me he had one but would have to find it. I did not think they made a SS prop for those motors but I was wrong. He had one well I have one now. What kind of rpms should that motor run? I'm trying to find a tach for it. I know somone mentioned Tiny Tach but I want to stay more in style with the boat. Any ideas? Thanks

 

[CATransplant]

Re: How Fast ?

It's really, really hard to find a tach for a magneto motor these days. It has to have an inductive pickup, since there's no place to get a tach signal. All the common marine tachs out there require a stator system to get the tach signal.

The Tiny Tach is about the only thing going that won't cost you more than the boat is worth.

As for RPMs, those Big Twins are rated for 4500-5000 rpm, if I remember correctly. I'd stick to that range.

It's extremely unlikely that the 13" prop will let you exceed that RPM range. I'm thinking that you'll reach it though, on your light boat.

For me, I'm so used to the sound of a Big Twin that I can tell whether it's running at optimum RPM, just by listening to it. The Tiny Tach will get you there, and you'll no longer need it once you get set up. You can mount it nicely right on the cowling, which works fine unless you're planning to have a pristinely restored vintage motor to go with your boat.

 

[tashasdaddy]

Re: How Fast ?

use the tiny tach to get it set up properly, it is just a temporary connection, and then use when testing.

 

[brownies]

Re: How Fast ?

That motor is not pushing a 300lb boat.

 

[CATransplant]

Re: How Fast ?

That motor is not pushing a 300lb boat.

Could you expand on that? Which motor isn't pushing a 300 lb. boat? I had a 1958 RDS-20. At 35 hp, it pushed my 700 lb trihull at 25 mph. This guy's 30 hp is going to do a fine job with his boat.

If that's not what you meant, can you explain what you meant?

 

[wbeaton]

Re: How Fast ?

Yes, please explain. My old 1953 25 hp pushed my 14.5' aluminum boat (about 600lbs running weight) at approx +20 mph.

 

[Brymill]

Re: How Fast ?

Update -- Ok guys I ran the boat yesterday with the 13 pitch prop and well it slowed the boat down to about 20 mph. I tried different trim setups and the that was the best I got which was the next to last hole out. That was one to much because it wanted to porpuse. The motor just did not seem to get up to the same rpms as before with stock prop. I've ordered a tiny tach so I can get a better idea of the rpms. Something that also concerned me was that after runing the motor @ wot it did not want to idle properly when throttled back down. It wanted to spit. I could adjust the slow speed on it just a bit to make it quit. It dose not seem to be moving but it takes a small adjustment counterclockwise to get it to idle properly. Anyway I'm starting to get frustrated with it. I have attached some photos on a run with the motor trimmed out to the next to last hole. They start with the boat coming oout of the hole to running @ wot. Let me know if you guys have any more suggestions. Thanks for your help.