Repair or Replace in Michigan?

[MittenFishin]

So I didn't want to threadjack, and I am a rookie boater so posting up my own question (and sub questions)

Here goes:
1) I saw a post about only a handful of "really good" prop shops across the country, and wondered if anyone has a name or two to suggest in the Metro Detroit area? Northwest lakes area preferred, but good work is worth a bit of a drive.

I'd guess there are several, but I'm a noob with his first boat.

I chewed up mine pretty well this weekend in unfamiliar waters.

2) When I got the boat it came with only one, so I was already doing research on getting a second for spare/different performance.

Here's my specs:
1984 19' Rinker bowrider. 3.8 4-barrel OMC stringer drive. I believe 120, or 150 horse. I'm working on confirming that. iBoats says 120, but I could have sworn I saw 150 some place.
I believe the boat is about 2250 dry, so normal fuel, gear and passengers put it a bit under 3,000# +/-

The original prop WAS an aluminum one in good condition. 14.25" x 21p Probably is repairable, but is it worth it? Looks like a basic replacement runs $165 or so new. I can make the calls to a shop, but I'd like to start calling someone good and going from there (hence the request for a recommendations!)

A couple of online calculators indicated it was probably a good all around prop for that set up. I believe it. From the couple of times I had it out, seemed "OK" everywhere. BUT...if I were to do something different, I'd be looking for more holeshot and power. The girlfriend already has plans for tubing with say 3-4 adults + 3-4 kids between tubers and passengers. On the other hand, her dad used to be a competition skier, and is looking forward to teaching his grand son. so it's up to me to make everyone happy!
so maybe I'm looking for a 4 blade 19p, AND a 3 blade 23p! (or make suggestions!)

3) The paperwork with the boat says "a cupped prop was provided for performance" and it looks like it may have been the original. From my readings so far, it seems cupped props are a bit more rare or specialized? Should I try to stay with a cupped one? Big deal or no?

Thanks for reading and any thoughts!
-Mark
(Added pics, cause everyone likes pics!)

 

[Slip Away]

Re: Repair or Replace in Michigan?

In D-town area. By far the best Prop shop is Johnny's. Don't bother with anyone else for repair or replacement. They are the best.

Johnny's Boat Propeller - Boat Propeller Sales & MRI Repair Analysis

 

[steelespike]

Re: Repair or Replace in Michigan?

I'm pretty sure a 120 is something like a 2.5. The 3.8 must be at least a 150.Also your adequate performance with a 21" prop would indicate the larger hp.I think take the prop to Johnnys And then do some runs with 3 or 4 adults and 3 or 4 kids.Get us the wot rpm and gps speed.
It surely will indicate less pitch is indicated And a 19" 4 blade may be the one.
And you will have to watch the rpm when lightly loaded unless you use the 21 when not doing water sports.

 

[MittenFishin]

Re: Repair or Replace in Michigan?

Thanks guys.
I'll check out Johnny's. They are about 15 minutes from my work, so like I said, I don't mind a drive to work with the someone good.

Slip: I think I wrote the prop specs the correct way, so maybe you misread (?) The current prop is 14.25 inches diameter and a pitch of 21, (cupped). (14 1/4" x 21p) Pic attached. The boat would definately not spin a 21 inch prop.

...and as far as engine RPM goes, I haven't been able to turn that up yet. I've reread the papers I got with the boat several times, and can't find it. I've also, spent an hour or two seaching the web and forums. I MAY have seen it once the same place I saw the 150 horse number, but forgot to save it, and haven't been able to turn it up again. Any help pointing me to better info on the engine's rating's and WOT recomendations would be greatly appricated.
I did break down the engine code, and it's clearly a 1983, 3.8 liter 4 barrel. OMC code: 384STMRCTR


I THOUGHT I saw max rpm of 4800 for this motor or a similar one, but again, haven't refound it to save/confirm.
I will say, that while I'm a noob boater, I am pretty in-tune with motor-stuff generally. She SOUNDS good up to 4800, and seems real happy on plane at about 4100-4200. I revved to 5000-5100 once or twice on the first day. (whoops!) didn't seem to do HARM, but was not happy. I thought this would've had a rev limiter or something...:facepalm:

 

[MittenFishin]

Re: Repair or Replace in Michigan?

A couple updates, and still happily accepting input/advise:

First I must have had my dumb newbie hat on too tight in my last reply and reading your comments.
Slip: thanks for the tip on Johnny's. They are ball parking $60-80 to fix my prop. I will get it there soon, but work keeps jacking me up on Mon/Tuesday. Johnny's says drop it off by Tuesday noon to get it back for the weekend.

For now I have just hammered and ground the prop back into the best shape I can to use untill I get it to them. Worked decent this last weekend, but I believe slipping a more with the chipped/ragged edges.

Steel: SORRY! I was the one not getting what you were laying down. Clearly you were adviseing on PITCH changes, per my request, and I was reading diameter changes. Honestly I'm not usually that easily confused! Again, claiming newbie syndrome.

So research has gotten me that the OMC 3.8 with 4 barrel carb was probably rated 185 (flywheel) with somewhat less at the prop. Max recomended WOT rpm 4800.
I ran it last weekend with 900#s of people, 3/4 tank of gas in the 2250# boat and performance was fine tubing. (so 3400#+ total weight) With the 14.25" x 21p banged up prop.
Even with this load I was able to over rev fairly easily, and had to watch not going 5K+ on the tac. This was with an OK hole shot and tubing.

So...I'm thinking if my loaded/tubing performance is good/boarderline under propped with the 3 blade 14.25 x 21p, then maybe a 4 blade 21p would add to the hole shot, suck up some power/rpms, and without losing too much off the top speed. (?)

...and NO I still haven't GPSed it yet for top speed. I'm GUESSING low-mid 40s as is. Speed speed is asways welcome, but the holeshot is my higher priority. I'll make getting a speed reading a higher priority next time I'm out, but untill I do get a new prop my numbers will be "off" with my ragged prop.

Thanks for reading.