What to do about this prop? Is it too beat up?

[Boomyal]

Re: What to do about this prop? Is it too beat up?

Originally posted by trog100:<br /> yes its quite clear they must weld new bits on to the old.. grind and reshape.. just kinda amazes me it can all be done so cheaply.. <br /><br />my own opinion is.. little dings and nicks get it "fixed".. bloody great chunks broken off (mine was like the one in the pics but on all three blades) buy a new one.. just the one low speed contact with some rocks instantly wrecked it.. i later found out it had been "fixed" by the previouse owner while he still had the boat..<br /><br />i dumped my old one in the marina trash area.. it disappeared straight away so someone must have thought it was worth something.. he he<br /><br />trog100

Yeah, they got a new prop for the price of a repair. Trog, I've torn complete blades off and they repair them for the same price. The come back good as new. You should even be able to change pitch or add cupping. As long as the hub is good they can fix em.<br /><br />I sure as heck would not run speedwagons prop. It'd make my lower end dizzy.

 

[BF]

Re: What to do about this prop? Is it too beat up?

Thanks to my dad, his I/O and the rocky shallow launch he uses. I'm on a first name basis with the prop guy... I've seen him at least twice a season for the last couple. Nasty looking damage too (way worse than shown above). Even fixed one where Pa managed to wind a rope around it and somehow crushed the leading edge of the hub where it sits behind the lower unit... when I pick it up he always says the same thing as he hands me a now new looking prop... "that was a bad one... how about $40?" Love that aluminum! <br /><br />They're not breaking because the repairs are bad/weak... they're breaking because they're supposed to push water, not be a rock propulsion system. Sorry trog, but whoever picked your damaged prop from the trash had the last laugh I think.

 

[trog100]

Re: What to do about this prop? Is it too beat up?

"Sorry trog, but whoever picked your damaged prop from the trash had the last laugh I think."<br /><br />yep i have to agree.. he he.. i dont mind buying the new one.. but i should have kept the old one and had it "fixed".. we live and learn.. <br /><br />trog100

 

[Speedwagon]

Re: What to do about this prop? Is it too beat up?

Bought a new prop, same size(actually, it is the exact same one). It's a Michigan wheel Vortex 14.5x19. BUT, I had it out today, and I can easily hit 5k RPMs with this prop, and WOT is supposed to be around 4800 I believe. It's an 88 Mercruiser 3.0L. I was topping out around 35MPH, and I'm pretty sure I should be able to go faster than that. So how much of a change do I want to make in the pitch/size to get better top end, and lower my WOT RPMs?<br /><br />And it turns out that my skeg steers me! It's slightly bent at the tip(of what's left), and trimmed down, I turn right. Trim up a bit, and it turns left. Kind of a pain in the but. I'll have to get that fixed soon.

 

[ErikDC]

Re: What to do about this prop? Is it too beat up?

Just so y'all know, rebuilding props has been a family business since the mid 60's, I grew up with it. In a nutshell, the prop is placed upside down on a steel form (we have a few hundred different makes and pitches, Merc, OMC, Volvo, etc.) that has been milled to the original blade form and then pounded back into shape with a wooden mallet. The hub will now be punched out if that repair is requested. From there the damaged areas of the prop are ground down and then the paint is buffed off the blades. The damaged areas are then heated up and the proper amount of aluminum is welded onto the blade with an oxy-acetylene torch. After cooling the prop is ground down to original specs using about 6 different grits of sanding belts. The prop is thoroughly buffed (the hub will be replaced at this point) and the prop will be sent off for painting. I left out a lot of details but that's basically how an aluminum prop is refurbished. It gets pretty freakin' hot in that shop, lemme tell ya!<br /><br />Edit: Charlie is about right on the repair cost, prop shops generally charge $12-$15 per inch of blade weld.

 

[JasonJ]

Re: What to do about this prop? Is it too beat up?

What was your load when you ran it? where you alone? You could go up one size, but you might want to put an average load in the boat and run it before you decide. You don't have a massive amount of power, and if you pull skiers or haul a lot of people, having the current setup will give you better holeshot. If you always boat alone, never carry weight, then going up in pitch would be useful. I am hoping you were checking speed with a gps, the speedometer would be inacurate. Mine shows a steady 3mph slower than I am actually going according to my gps. I don't even know why I have the speedo, sometimes it does not work at all due to some junk in the pitot. Anyways, good luck...

 

[reference123]

Re: What to do about this prop? Is it too beat up?

Originally posted by rogerwa:<br /> Next time I need a prop, I'm going to try a Piranha. $20 a blade doesn't sound too bad to me. I boat in an area where I have to idle through some pretty shallow areas and will often hit submerged logs or something else. I have already damaged two props in the 2 years I have been boating in this area.

I put one of these on about a year ago (omc 225 hp in/out) and have been very happy with it. Went with the 4 blade which performed noticeably better than my 3 blade aluminum. And I like the fact I can replace a blade for 20 bucks or repitch it for $80 if I go to sea level.

 

[BF]

Re: What to do about this prop? Is it too beat up?

ditto what JasonJ said about the pitch. Even if you decide to go up in pitch, keep your current one as as "ski/tubing" prop. It will help you hole shot immensely. FYI, my dad has an older 70's merc 3.0, and he runs either a 21 or 23" (I forget) on a 17 1/2' glastron.<br /><br />Just a comment on the steering... it might be made worse by the skeg, but what you're feeling is probably mostly torque steer. It's common for it to change with trim (and even to change from one pull to the other). OB's often have a trim tab (little fin) behind the prop that is adjustable. You try to make the steering neutral in your common cruise trim. Many I/O's don't have this adjustment... and other than fixing your skeg, I think you just live with it.<br /><br />edit... just looked at your pict again... you do have a trim tab (also serves as a zinc anode)... so after getting skeg fixed, adjust it to neutralize the steering in cruise.

 

[Speedwagon]

Re: What to do about this prop? Is it too beat up?

I was alone when I ran the 19p prop. I exchanged it for a 23p prop. The guy even looked it up in a book, and it recommended the 23p for this size boat. Took it out on this prop, and it does MUCH better. I get hit WOT now no problem without fear of overrevving, and it gets up and goes nicely. I can tell the hole shot isn't quite as quick, but it isn't bad either. So once I get the original 19p refabed, I'll have a good speed and power props for the needs of the boat.<br /><br />I was only checking speed with the speedometer(pitot), but that wasn't really what I was basing my decision off of. I gathered from this board that RPMs are the key factor, and I was overshooting recommended WOT by quite a bit with the 19p, lightly loaded. And the boat is going to be used part time by my little sister when she's ready, and I don't want her to be able to overrev it as easily as I could with the 19p prop on there too.<br /><br />And I got a quote for $100 on the skeg fix. Does that require me taking the lower unit off generally? Or do they take care of that?

 

[BF]

Re: What to do about this prop? Is it too beat up?

I'm pretty sure they'll just fix it on the boat. No need to pull outdrive.