Bought a used prop

[bbroskey]

I have a 1978 Johnson 75hp Stinger and I recently bought a great condition used prop that came off of an Evenrude. I just took the boat out for the first time with the new prop and it seems like it won't get out of the water. It takes it a long time to get up on plain with just two people in the boat. With a lot of weight in the boat full throttle it barely makes a wake. Could this be a prop issue or could it be something with the engine not getting enough oomph and just bogging down ? Like a sparkplug gone bad or something ? Any help would be great.

 

[zzzzz]

Re: Bought a used prop

take the prop off and get us any numbers off of it so we know what you have propwise

 

[M.Magis]

Re: Bought a used prop

Need more info. Was the prop the same pitch? Did you put the old one back on and try it?

 

[bbroskey]

Re: Bought a used prop

I can I find out what pitch I need for my engine ?

 

[bbroskey]

Re: Bought a used prop

The last entry is suppose to say How can I find out what pitch I need for my engine ?

 

[Fouled Plug]

Re: Bought a used prop

If you don't have a tach, get one. It's a must to prop a boat correctly. Did the boat perform well with the old prop? How do the numbers compare?

 

[bbroskey]

Re: Bought a used prop

When I get home tonight I will have both the OLD Props numbers and the NEW Props numbers and I will post them tomorrow. Please check back tomorrow to see if this is my big mistake. Thanks to all that is helping.

 

[bbroskey]

Re: Bought a used prop

Ok the OLD prop's numbers are pretty worn but here is what I got off of it 510H 816TL 224. The new prop reads 612714c 31/4x17. Not sure what this means, but please help.

 

[zzzzz]

Re: Bought a used prop

the new prop appears to be 13 1/4 diameter by 17" pitch with an OMC part# but the old prop numbers...not familiar with that manufacturer's numbers...you can send it to a prop shop and they can tell you the pitch and repitch the new prop to that pitch...and also have the hub checked

 

[bbroskey]

Re: Bought a used prop

How can I find out what pitch is right for my engine ?

 

[zzzzz]

Re: Bought a used prop

go to www.miwheel.com thats Michigan Wheels' website..there should be a page where you fill in info about motor,kind of boat,loads,etc and they'll suggest the pitch you need

 

[Solittle]

Re: Bought a used prop

bb - We would be better able to help if you shared what kind of a boat you have this on. Big difference in props for the same engine if you are runnin a 16' or a 26'.

 

[bbroskey]

Re: Bought a used prop

The boat is an old 1977 Fiberglass Lund. I think it is a 16ft.

 

[roscoe]

Re: Bought a used prop

I think the new prop you bought has a spun hub and needs to be rehubbed, $40 at a prop shop. I also think you need a prop with a lower pitch. Something like a 13diameter x 13p.<br /><br />Put the old prop on and take it for a ride. If it works, then you don't have an engine problem. <br /><br />Take the new prop and mark a line on the inside, from the inner edge of the hub, out to the outside of the housing. You can use nail polish or scratch the line onto the prop with a nail. Put it on an take it for a ride. Do several full throttle hole shots. Then take it off and see if the line is still lined up. If it isn't straight and lined up anymore, then your prop hub has spun.

 

[bbroskey]

Re: Bought a used prop

The more I keep reading about prop pitch and everyone's responses I am almost definite that the prop pitch is the culprit. Once the boat gets up on plain it will run fine its just the problem off not having enough rpm's it seems like to push it out of the water with a skier or a lot of weight in the boat. I appreciate everyone's knowledge and I am taking the new and old prop to the local boat shop to see if they can tell me what pitch my old prop is. Thanks again for the help. I hope once I get a the proper pitch the boat runs better. Please do not hesitate to confirm my theory by replying. It will make me rest easier if everyone agrees with it.

 

[karayj]

Re: Bought a used prop

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&rd=1&category=26456&item=2420984955

 

[bbroskey]

Re: Bought a used prop

Ok, I took my old prop to the two different boat shops and they were unable to tell me the pitch. The only information they could give me was that it was a J 80. Not sure what that means does anyone else ?

 

[bbroskey]

Re: Bought a used prop

Ok, I took my old prop to the two different boat shops and they were unable to tell me the pitch. The only information they could give me was that it was a J 80. Not sure what that means does anyone else ?

 

[Hooty]

Re: Bought a used prop

BUMP

 

[John OMC]

Re: Bought a used prop

I think your "J-80" is actuall a PJ-80 Michigan wheel. An alpha numbering system discontinued in the mid 90's. The size is a 13-3/4 x 15 without a cup. If you are running a 17 pitch now the motor will lug and you are loosing about 600 rpm. Any competant prop shop can repitch that prop down to a 15 for about 30 bucks. Your RPM's will increase and you'll be back up on plane again.