2007 optimax 90hp lower unit install

[parkcity]

#1B350045

on day 2, tried and can't get the lower unit the last 1/8th inch after an impeller service. tried for 1 hour yesterday and another hour today after some research but the lower unit always stops dead and won't budge the last 1/8th. I know I'm missing something but can't figure it out at this point. The shift shaft is engaged, at least somewhat as I can move the throttle to F N R and the prop follows suit. i installed it in N.

the drive shaft seems to generally be engaged as the fly wheel turns the prop and vice versa.

the back end seems like it wants to fully mesh as i could probably force the gap shut but something up at the front is absolutely not moving.

thanks in advance

[JOE54]

if it only like 1/8 its probly just dowells not ingaged in holes snug it a lil with wrench

[SilverFox579]

My 2.5L Optimax has been that way since new and have always had to draw it up using a wrench to fully seat dowels.

[parkcity]

ok great, i've been using a ratchet strap for a second set of hands as it gets heavy fiddling around for an hour. i will add the washers and nuts back on, tighten them up and report back

this makes sense as it was a pain getting off in the first place, needed some solid whacking with a mallet - (drive shaft splines were not corroded)

[JOE54]

OMG dont be whacking on nothing thats gold under that black paint

[EuropeanAM]

OMG dont be whacking on nothing thats gold under that black paint

You got that right!

Also- make sure you don't have any grease ON TOP of the driveshaft. Splines: Yes. Top of driveshaft must be dry.

[parkcity]

ok noted- i used a rubber mallet and a wood buffer so i don't think i did any surface damage but the lower unit wasn't coming off without persuasion. In the future would you suggest gently prying at the seam then if this lower unit will continue to stick both on and off ?

[EuropeanAM]

Don't pry- that's a good way to damage something. Rubber mallet (within reason) is normally sufficient.

[parkcity]

RESOLVED.

Thanks Joe, Silverfox & Don. I added the nuts back on and it sinched right up with the wrench.

[JOE54]

[SilverFox579]

That's what I have to do every time I service my lower unit, including a plastic dead blow to get lower off the dowels. Next time I have lower unit off I'm "massaging" the dowel pins and/or holes as the lower unit isn't getting any lighter and I'm sure not getting any younger.