gear ratios merc 90hp

[bobvdinghyracer]

a buddy of mine has a 1999 merc 90hp triple ... said the gear ratio is 2.3 and he is wondering what are his options if any ... goal is to drop it down to ?? what fits if anything and what is avaible anybody..... this is on a full size 14ft 3 point hydro / jackplate etc ... runs in mid 60`s / he wants to drop the gearing so he can run less pitch and diameter he believes that he has way too much bite for the boat and wants a lot of pitch with less diameter , he has several smaller dia, props but they do not have enough pitch for the current gearing ................. anyone ??? my ecpertise is with the smaller engines / hydros an utilities not the bigger motors btw (started with a 17p and has gone all way to a 26 ... motor still will run up over 6000 plus with no problem):)
http://i218.photobucket.com/albums/cc164/bvrevrev/mikes%20hydro/IMG_0430.jpg

[88workcar]

The only other option is a 2.07 gear. $800.00 worth. it is better to find a late model 115 lower (2.07) or order a complete aftermarket L.U. I just did a 115 lower for a customer the merc gear prices are rediculous.

Well there are more options. Cut and weld a old school mid bottom in place of yours and use a XR4 small gearcase, that is a 1.78, and has the option of going with 1.87 and 2.0 gearing. I just got a XR4 L.U. to adapt to a 90 yammi

Also, that particular Merc does not like trips over 6000, get ready.

[bobvdinghyracer]

correct me if i`m wrong but this motor is a half breed aint it ? meaning part chrysler / block wise and merc ign / mid is ?? and gearbox is merc .... looks just like the 90 hp jet boat engine ,like the older bayliner jazz for example which was a chysler engine , tho it was decaled " merc jet" , i`ve seen a few of these come apart ! anywho ......... back to gearbox so ..... nothing else will " bolt up " ?? as far as modding the leg it is possible as we are both capable of fabbing / welding it up ...but i dont think he wants to go that way if it was mine that would allready have been done , if i was inclined to build a boat that LARGE ... i like the little guys ... doing up a gw invader currently ... cause it followed me home 1 day ... that will have a modded 44 cube merc on it most likely
dinghyracer out :)

[Fastjeff57]

While working a boat show (USCG Aux) over the weekend at a Merc dealership, I passed the time by reading their manuals--and there were hundreds of them! (Had a ball.) I seem to recall that the 90 hp motor in question was factory available with 1.63:1 gearing. (I'm absolutely positive that the later, 40 to 60 hp triples were available with that ratio.)

I doubt if that 1.63:1 ratio used the same housing, but they did offer it (on the smaller triples at least).

Jeff

[88workcar]

The 60 for sure. not the 90

[mercguy]

correct me if i`m wrong but this motor is a half breed aint it ? meaning part chrysler / block wise and merc ign / mid is ?? and gearbox is merc .... looks just like the 90 hp jet boat engine ,like the older bayliner jazz for example which was a chysler engine , tho it was decaled " merc jet" , i`ve seen a few of these come apart ! anywho ......... back to gearbox so ..... nothing else will " bolt up " ?? as far as modding the leg it is possible as we are both capable of fabbing / welding it up ...but i dont think he wants to go that way if it was mine that would allready have been done , if i was inclined to build a boat that LARGE ... i like the little guys ... doing up a gw invader currently ... cause it followed me home 1 day ... that will have a modded 44 cube merc on it most likely
dinghyracer out :)


no, its not a "half breed", its all Mercury built.............if interested, I have a nice L4(100-125hp) lower unit that might help your friend out............PM me, if interested.....