Best prop choice for a 150 E'rude on a 17'8 Bumblebee

[H1990]

Any advice on what prop to run on this set up that would give me the best top end? Right now i have a 24p turbo 3 blade that is pushing it around 63mph at 5600rpm. Wondering about going to a Raker 24p, or a Powertech 25p, or a Ballistic 25p 4 blade? Any help would be appreciated.

 

[Ron G]

Re: Best prop choice for a 150 E'rude on a 17'8 Bumblebee

Nice to see another bee owner,your running good,do you have a jackplate?and if so how high is the cavation plate from the bottom?your still a little under the rpm range with the 24 but this cooler weather will raise that a little and if ya can raise the motor any it will rise and give ya better performance too.What year are you running?it must be a newer and lighter model.are you sure the tac is correct first.and has the 150 been modified?

 

[H1990]

Re: Best prop choice for a 150 E'rude on a 17'8 Bumblebee

It's a 1985 Bee with a 1979 150 Rude on it that was rebuilt by the OMC dealership in Birmingham in about 2000-2001. It has a 24p turbo on it now. It does have a jackplate. I'll have to check the height on the cavitation plate. Am I sure the tac is correct...no. The mechanic that reworked the motor said he set it to where it would stay below 6000rpms. Don't know if he did that with timing, or what.

 

[Ron G]

Re: Best prop choice for a 150 E'rude on a 17'8 Bumblebee

I went back and read your your other thread.lets see were your height is.are you venting any yet?have you got to do some good runs since its been out of the shop.i dont know what he could he have done unless he lowered the motor maybe dale can give us some ideas on that.if your water preassure is good lets start jacking that baby up a little and see what it does..with that 150 on it you should be able to fly.and is that the super bee??the turbo is a great prop, are you getting good bow lift with it?i didnt get that much with the turbo 2 but the txp gives me all i want in all departments.im still fine tuning my setup too.we should be able to get ya were you want.but you know the faster you go the faster you want to godand make sure you listen to dale he's awsome.

 

[H1990]

Re: Best prop choice for a 150 E'rude on a 17'8 Bumblebee

Actually the boat is still in the shop. I swapped a buddy of mine today that 24" Turbo for a 24" Raker that I'm going to put on it when I get it back (He also has a 22" and a 26" if either of them works better than the 24"). When we put the 24" Turbo on the gauge at his prop shop, it actually read 22.5" even though its supposed to be a 24p. The buddy of mine that has the prop shop has the same boat (no it's not a superbee) and he said to try that raker b/c the bow lift would be better than the turbo. I know looking at them there is a big difference in the length of the prop.

 

[Ron G]

Re: Best prop choice for a 150 E'rude on a 17'8 Bumblebee

The older rakers are a good prop,and alot of the bees run them around here.i got away from the 4 blade they didnt responded as well as some of the 3 blades that i've tested yet on my hull.send me a pic if ya dont mind of the boat.rogreen@sewanee.edu

 

[H1990]

150 E'rude on a 17'8 Bumblebee...BAD Chinewalk & Low Rpm's

150 E'rude on a 17'8 Bumblebee...BAD Chinewalk & Low Rpm's

Ok. I finally got my boat back and am trying to get it set up. Here's my problem:

Boat has a 6 in jacker. Former owner had a 24p Turbo on it that he said turned 63mph @ 5600 rpm's.

I wanted to put a 24p raker on it
It wouldn't turn but 4700 rpm's and 56 mph. If I tried to trim it all the way up, it chinewalked so bad that I couldn't hold it.

I measured the jacker and prop shaft. The shaft was sitting about 4 inches below the bottom of the pad.

I tried a 22p raker. It now turns 5100 rpms but still about 55mph, and still have same chinewalk problem. I know they say to drive through it, but I simply can't...the bow is swerving to the point I'm scared it will throw me out.

I wondered if my tach was working, so I put a 19p aluminum on it (standard rake oem prop), and it didn't chinewalk and the rpm's would have gone to probably 6000 had I kept trimming it. Speedo said about 51.

I spoke with the prop man and he said the raker was probably the best prop for the boat and the 150, so his suggestion was that I raise the motor 1 3/8 inch (after I put a water pressure gauge on it) and he said that should help the chinewalking. He said that the prop shaft being 4 inches below pad was too deep. He said that the boat would chinewalk less the higher I raised the motor because the chinewalking was caused by the water off of the pad hitting the cavitation plate and making it squirrel. I would have thought that dropping the motor would be the answer, no?

The jackplate also was tilted to the back position to where the foot of the motor was kicked under the boat (about 1/2 inch in the height of the jackplate), and the prop man said this was not what we needed. He said it should be parallel to the boat transom.

Here's my question: Is raising the motor the answer? Also, as light as this boat is (It's been rebuilt with 100% composite stringers, floor and transom), shouldn't I be able to run a 24 pitch and get the rpms?

I'D REALLY APPRECIATE ANY ADVICE ANYONE HAS

 

[Ron G]

Re: Best prop choice for a 150 E'rude on a 17'8 Bumblebee

you should be able to run the 24 easy,lets raise it up to around 3"below the pad and see what that does.hows your lift with the raker?it may take awhile to learn how to drive it threw the chinewalking its all a balancing act.but raising it should help by theory,set-up is the fun part you keep adjusting until you find that sweet spot.also theres something else but will talk later about that.run the 24 and keep your eye on the waterpreassure.and you may want to verfy your tac to make sure!lets see what Kenny and Dale think.
""The jackplate also was tilted to the back position to where the foot of the motor was kicked under the boat (about 1/2 inch in the height of the jackplate), and the prop man said this was not what we needed. He said it should be parallel to the boat transom. "" mines like that also it actually helps a little with hole shot i think.

 

[H1990]

Re: Best prop choice for a 150 E'rude on a 17'8 Bumblebee

Ron,
Thanks. I actually raised the plate yesterday evening when I got back, but haven't got a water pressure gauge yet...i will this week. I raised the prop shaft to about 2 3/4" to 3" below the pad. Help me understand...how does raising the motor help with chinewalk? I'm confused...trusting, but confused. Also, what was the "there's something else but will talk later about that"?
Heath

 

[Ron G]

Re: Best prop choice for a 150 E'rude on a 17'8 Bumblebee

It all depeands about the raising,some do actually help with it lower but you dont have the speed.when you raise your motor you have less drag from the gearcase which also means cleaner water.another thing may be your setback i dont think 6" is enough most bees i know run 8 to 10 back.that could hamper with your walking too.im still learning also how to drive at faster speeds but the only way to learn is seat time and it dont take much wheel action at all to straighten it out.