Prop question for a motor newbie ..

[HammondSeaRanger]

I have a 100hp, 1980 Johnson Javelin. I need to replace the exsisting prop.

Can anyone tell me if this one will fit? :shrug:

http://www.ifish.net/forum/showflat.php?Cat=&Number=722515&page=&view=&sb=5&o =&fpart=&vc=1&PHPSESSID=

[trap50]

Sent you a E-Mail Hpoe it helps. I have a 115 hp evinrude. Seattle propeller set me up with a 143/4 X21" S/S Renagade. Works real well on my boat. Got the RPMS down to 5200. Big thing to watch so you aren't over reving.

[fineline]

Sent you a pm. Also if it's a 1980 model it doesn't seem to be a c-4. They made them around 1984.

[HammondSeaRanger]

how can I tell if its a c-4 ?

[fineline]

Look at the PM I sent you with the link to a manufacturing website that lists the info for Johnson Outboards. Notice the motors are listed by year of manufacture. There are two 100 HP motors listed and if I remember right the 100 HP c-4 model wasn't made until 1984. I guess you have to figure out exactly what year your Johnson is. Here are the two that may apply.

1979-1980 100 HP 100 HP (Thru Hub Exhaust & 13 Tooth Spline)

1984-1990 100 HP 100 HP V-4 Commercial (Thru Hub Exhaust & 15 Tooth Spline)

After futher investigation, looks like it boils down to how many tooth spline the prop has your looking at as well as the one your replacing. 13 or 15?

[HammondSeaRanger]

Ok,

Dumb question #2 ...

what is a spline?

I am sure its 1980 .. I checked the serial # off the Johnson web site.

Matt

[fineline]

Should be the inside of the prop that goes on the shaft. Dictionary states; a rectangular key fitting permanently into slots in two parts of a mechanism, e.g. a shaft and a wheel,(prop), ensuring that these revolve together and giving maximum strength //either of these slots.
Look at the second picture of the prop. Looks like the spline in the center of the prop. Count the teeth.