TOPIC: Prop help/question?

OK, so Bob the idiot (me) was able to find the only chunk of something in the water close to where we always ride. Been by the same section just the week prior and nothing. Saturday, going about 8 mph bumo and up comes the motor, thank god she wasn't locked!

So now to my question, am I ok to use this prop again this weekend before I find another one?





The skeg is fine, the big chunk is new and the little bends are new. Doesn't look like the shaft bent either. The part number form the old maual says 278155. I have another one but it's much worse than this one. Apparently dad found plenty of rocks and logs in Lake St. Claire.

It's a 12 1/8 x 14 prop, at least that's what the box for the other one says.

Noy having a lot of luck finding one local either.

Any suggestions on if ti's ok and where a good place to find another reasonabley priced one?

Bob

Balance is what you need

You can take some off the other blades as to balance it..put it on a welled oil shaft and spin it as to see where it stop...if the same blade ends up on top then the other two needs to be filed down

Not cheap but they are good

www.propcopropellers.com/evinrude_Outboard_Prop.htm

or send on to be rebuilt

www.propmd.com/

ask around your area for a prop rebuilder. I know of one 30 miles away that I should take at least one prop to (either swap or wait for rebuild) to remount/replace the hub rubber.

BTW, is there a reliable way for the average boater to measure the pitch of an unmarked prop?

I don't think I'd take a chance running it that way if it were mine, Bob. It's gotta be out of balance, and could cause bearing and seal damage in the LU, which could get expensive quick! Just my two cents, I'm no expert. Sorry about your bad luck there buddy.

Mark,
Thanks for the input, that's what I was thinking also.

n0ukf,
Thanks, will try that, not sure if there is one, seems like most of the "old guys" who knew how to work on these classics and stuff have all completely retired and don't do it any more. I'm going to check though, I know I can't be the only knuckled head who's doen this around here! Sorry don't know how to measure that, the one I knicked is an un marked one also, just assuming it's like the old one in the box. Put them next to each other and looked exactly the same.

Tall Texan,
Thanks, I'll try that, at least it will get me through the weekend and time to hunt for a fix or new one.

I did find a 12 x 13 on Ebay that's suppose to be for 50 to 90 hp Envinrudes 17' to 19' boats. According to the data I found the 12 1/8 x 14 is suppose to be for 14' to 16' boats. Maybe I'm actually running the wrong prop?

Bob

If this is the 100 HP motor V-4 then you could try a 16" pitch.

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Used to ski behind a 17' Deep V boat with 4 people and 2 on single skis.

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No problem at all.

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You can run that prop for a while ( week end ) if you have to.----Damage can be done if you run it long term.

Professor, sorry my bad I should have said it's on a 1959 Fat Fifty.

Bob

Ever look at the bearings in a fat 50 lower unit??

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That little bit of damage will not harm them.-As far as I know there was only one prop offered for that 50.

Professor,
I know the other bad one is a Michigan Wheel PJ-50 which is 12 1/8 x 14 but when I did some searching it says that it's fro 14' - 16' boats. I also founf on Ebay a Pj-61 that's 12 x 13 and is suppose to be for 17' - 19' boats. My Clipper is an 18' so I'm curious if I can get away with that one since it looks new and what will it do to the motor. I can't remember if going down in pitch raises or lowers the motor RPM.

Bob

Bob,
Going down in pitch is akin to shifting down in your car - RPM goes up! You gain pulling power at the expense of speed. Also, worry less about the "boat size" recommended and go by actual RPM when choosing a prop. Things like load, hull design, set-up, etc. all come into play and can throw their recommendation out of whack. Ideally, you want a prop that peaks out a little above the high end of your motor's recommended operating RPM range (with a light load), which leaves you some wiggle room when you take on passengers and gear. Can't recall off the top of my head, but I think the RPM range on your motor is 4000-5000 RPM with the hp being rated at 4500. Aim for a high reading of 5000-5100 RPM.
I concur with the Prof - as long as the prop isn't bent, those little dings won't hurt much short term.

Thanks Scott. I think my best bet then is to spin that prop and balance it out for now. Once I hot rod the motor, I'll probably have to change props anyway. I'll have to check with Bruce and see if he did. I have another new project coming home soon so I need to get the hot rodding post/work done and repaint the cover before I can start on the new project. Oh yeah have to finish the honey do cupboards too!

Bob

OK couldn't use the old Merc prop shaft since it didn't want to spin too well with the splines and the two opposing hey grooves on the Rude prop. I had an old vinyl covered metal mop handle that was pretty close to size. prop spun pretty good on it. Did some initial filing and some spinning and it seems to stop at random positions, so I think I'm good. It's not real pretty but functional. Now it's time to comb the local marinas and see who has what before I go on line.

Thanks everyone for your help, I truly appreciate it, I can't thank you enough.

Bob