Re: 1979 mr1 260 lower unit install
Probably you had the remote control not in the same gear as the gear housing, or you missed the right spline tooth on the shift shaft by one. Most people prefer to assembly the gear housing to the drive-shaft housing when both are off the boat. Some people think it's easier that way... Personally, I don't have a problem either way.
If you're doing it with the drive still on the boat, then trim the drive all the way up and remove the gear housing. Put the remote control in FORWARD and ensure it is in FORWARD by looking at the coupling between the upper shift shaft and the intermediate shift shaft. The little 'shoe' looking thing should be facing directly forward.
Then, while turning the prop shaft CCW, turn the lower shift shaft (at the front of the gear housing) CW until it stops. This engages FORWARD in the gear housing. DO NOT turn the propeller shaft CW from this point on, or the gear housing will be knocked out of FORWARD.
While holding a bit of pressure on the prop shaft in a CCW direction (some people use a bit of bungy cord) offer the gear housing up to the drive-shaft housing. Watch the water tube and make sure it enters the tube guide on top of the water pump while pushing the housing up. If it stops before the splines engage, turn the prop shaft CCW until the splines do engage. At this point you should now be watching the shift shaft and ensuring they engage properly.
Once everything is engaged put the front nut on by a couple of threads. Then let the gear housing drop down a little (maybe 1/2"). This is so you can get the side nuts on. Put these nuts on and continue the 'button up' process....
HTH,
Chris........
