Minnesota Classic Glastron Forum

General Category => General Discussion => Topic started by: M1dtom on March 26, 2017, 01:34:38 AM

Title: hub diameter of lower unit 86 merc 115
Post by: M1dtom on March 26, 2017, 01:34:38 AM

hi everyone, , my name is tom and I just bought a 86 cvx 16 with a 86 merc 115, for $2600 nice shape,
I just joined forum and haven't did  profile or pics yet,
I haven't even test drove it yet. why question is it has a alum prop pitch unkown cant find #s on prop? just bought a nice laser2 for a 100. bucks for merc 15 spline, the inside hub is 4.25 and didn't fit,, looks like myine is 4in dia hub is that correct? the reason im asking is because the owner said he replaced lower unit and I just wanted to be sure 4in is the right dia of my lower unit? before I order a stainless from else where. I want a spare for first ride as I live in ma and no other boaters around if I trash prop during first ride!!
thanks tom

Title: Re: hub diameter of lower unit 86 merc 115
Post by: carlsoncvx18 on March 26, 2017, 07:32:29 AM

welcome to the forum we all want to see pics of your cvs.

I think and somebody will correct me but the inline mercs run the small hub and the larger V6 and mercrusiers run the large hub.

Hope that helps you out as your motor should run the smaller hub prop.

Title: Re: hub diameter of lower unit 86 merc 115
Post by: Hyperacme on March 26, 2017, 09:33:05 AM

Welcome to the forum Tom !

Dave is our prop expert and will correct any of my errors below ...

Pretty sure any LU from late 60's to mid 2000's fits Merc motors from 65 HP to 125 HP, 4 & 6 cylinder motors.
They might have different drive ratios, but you can adjust with prop choices.

Laser II props use to be odd number pitch (21P, 23P) were for V6 outboard and I/O drives, even numbers (20P, 22P) pitch were for the lower HP (125 HP and down) outboards.
New (2016) Laser II's now are every pitch, but cost over $400 !
You want a newer style with "Flo-Torq" hub and round vent holes, used ones on Craigslist go for about $200 to $250

Laser II props ...
https://www.mercurymarine.com/en/us/propellers/sport-series/laser-ii/ (https://www.mercurymarine.com/en/us/propellers/sport-series/laser-ii/)

I'm running a Laser II 22P on my boat at 52 to 54 MPH/GPS.
After testing a bunch of props, it was the best all around prop.
Below is a Merc prop chart from 1991, but part numbers should help when looking for a used prop.

Title: Re: hub diameter of lower unit 86 merc 115
Post by: M1dtom on March 26, 2017, 10:43:15 AM

thanks guys appreciate your help, the prop i bought a laser 2  48 816296q2 21p.
thought i scored a great deal.