Please help me get my prop to fit

[derek4325]

Prop swap. Hub kit?

Hi everyone, I'm currently trying to change out my original 19 pitch prop with a 21 pitch. Im replacing the omc prop with another omc. The new prop is "deeper" than the old and the trust washer is a pretty sloppy fit in the the new one as where the old one it fits freely, but not nearly as much play. With the prop being deeper, the original spacer is too thick and if i take the spacer away the prop nut will bottom out on the splines. Will a hub kit fix my probem with the spacer and the thrust washer? If so what hub kit do i need? Its a 1988 cobra drive with a 5.7 chevy. Part # from the "new" prop is 391202 if that helps any. Any input is appreciated. Thanks everyone

 

[derek4325]

I posted this same question in the OMC spot not seeing this page so i apologize for that. Here is my copied question.

Hi everyone, I'm currently trying to change out my original 19 pitch prop with a 21 pitch. Im replacing the omc prop with another omc. The new prop is "deeper" than the old and the trust washer is a pretty sloppy fit in the the new one as where the old one it fits freely, but not nearly as much play. With the prop being deeper, the original spacer is too thick and if i take the spacer away the prop nut will bottom out on the splines. Will a hub kit fix my probem with the spacer and the thrust washer? If so what hub kit do i need? Its a 1988 cobra drive with a 5.7 chevy. Part # from the "new" prop is 391202 if that helps any. Any input is appreciated. Thanks everyone

 

[Lou C]

I used Michigan Wheel aluminum props exclusively on my Cobra and never had one fit any different than the rest...

 

[Chris1956]

Normally a prop will provide thrust washer info for a particular application. Is your prop designed to fit your outdrive?

If not, you are on your own to fabricate something that will work. That shouldn't be too hard. Some combination of washers of the right size and the old thrust washer should work.

Heck, I ran my MercuryOB props on my Johnny, by drilling out some of the spline length and fabricating a thrust washer out of a Merc one. A little grinding was necessary to make it fit.

Do not run without a thrust washer, or it will likely wear down your outdrive.

 

[derek4325]

Yes definitely wouldn't run without a thrust washer, but to answer your question, yes the prop is designed for my boat, and no it did not come with a thrust washer, trying to use the old one. One would assume that they would be interchangeable especially considering they're both for OMC cobra. We all know what happens when you assume. Seems as if i need the proper thrust washer and the proper spacer. If i have to cut down the existing spacer to make it work i will but i perfer not to do that if i dont have to.

 

[Bondo]

One would assume that they would be interchangeable especially considering they're both for OMC cobra. We all know what happens when you assume. Seems as if i need the proper thrust washer and the proper spacer. If i have to cut down the existing spacer to make it work i will but i perfer not to do that if i dont have to.

Ayuh,..... Prop mountin' kits, follow the prop,..... Not what yer puttin' the prop on,.....

 

[jimmbo]

What was the part number of the old prop?

 

[QBhoy]

Ayuh,..... Prop mountin' kits, follow the prop,..... Not what yer puttin' the prop on,.....

You won’t get better advice than this.

 

[derek4325]

OMC prop # is 391202 thank you for the responces everyone.

 

[derek4325]

Does anyone know what thrust washer and spacer (assuming i need a spacer) i am going to need to make this work? Sorry if this is one of those questuons that gets asked a billion times, im a newbee with these sorts of setups, im more used to motors from the 60s and older lol

 

[Chris1956]

Normally the prop[ manufacturer will have information linking prop, spacer (if necessary) and thrust washer to a particular application. It is usually in table form.

With some checking you look to need Thrust washer 126870. I suggest you verify.

 

[derek4325]

Normally the prop[ manufacturer will have information linking prop, spacer (if necessary) and thrust washer to a particular application. It is usually in table form.

With some checking you look to need Thrust washer 126870. I suggest you verify.

Thank you, i was starting to lean toward that particular washer as well, as you suggested i would like to call somewhere and varify the correct# since OMC has been out of business for almost 20 years maybe i could call BRP?

 

[Chris1956]

You want to call the prop manufacturer. Make sure you have the motor size and year correct. Some of the sites only had listings for '88 Cobra with a 5.8L motor. Not sure what motor that is.

 

[derek4325]

You want to call the prop manufacturer. Make sure you have the motor size and year correct. Some of the sites only had listings for '88 Cobra with a 5.8L motor. Not sure what motor that is.

The prop manufactor is OMC (or some unknown company made it for OMC) thats why i was confused as to why the old thrust washer wouldn't fit. I measured my old washer and its 7/16" thick. I just ordered the part # you sent me because thats 9/16" thick. As long as it fits snugly into the new prop ill be good, if not i guess im out $12.

 

[Owennine]

Hmm, is that so? Thanks for the tip!

 

[Owennine]

By the way, just in case anyone's interested. My brother Joe is selling a few 16-Inch Black Performance Wheels. If anyone's interested, feel free to PM me.