70hp lower unit drop. Shift linkage???

jbakerinc

Seaman Apprentice
Joined
Jan 2, 2009
Messages
38
How do I disconnect the shift linkage to drop the lower unit on a 1982 70.

I can see what looks to be a bid star bit. and maybe a side set screw??
 

ajgraz

Lieutenant Commander
Joined
Mar 1, 2010
Messages
1,858
Re: 70hp lower unit drop. Shift linkage???

Dropping just the foot (i.e., not the mid-section also)? If so, you don't need to disconnect anything having to do with the shift linkage. You do want to be sure you are in neutral and that the reverse lock cam stays in the right position when you reinstall.

Having trouble getting the foot to come off? Did you find all the bolts and nuts, including the hidden one under the anode?
 

jbakerinc

Seaman Apprentice
Joined
Jan 2, 2009
Messages
38
Re: 70hp lower unit drop. Shift linkage???

just need to replace the impeller. found all the nuts and bolts hidden and all. will drop aprox. 1/2 inch and wont come clean off.
 

ajgraz

Lieutenant Commander
Joined
Mar 1, 2010
Messages
1,858
Re: 70hp lower unit drop. Shift linkage???

If it drops 1/2" evenly all around, then all the hardware is disconnected...you did totally remove the 5/8" (?) nut on each side of the foot, right?

Maybe the drive shaft splines are stuck in the bottom of the crank? Try jostling the flywheel back and forth while pulling down on the foot. Use some anti-sieze on the drive shaft splines when you reinstall. Shift shaft splines could be sticking I suppose, use anti-sieze there too on reinstall.

Or maybe the water tube is sticking in the pump housing, try jiggling the foot around while pulling it. Use some vaseline to lube the tube when you reinstall.

Have you had the foot off before?
 

jbakerinc

Seaman Apprentice
Joined
Jan 2, 2009
Messages
38
Re: 70hp lower unit drop. Shift linkage???

If it drops 1/2" evenly all around, then all the hardware is disconnected...you did totally remove the 5/8" (?) nut on each side of the foot, right?

Maybe the drive shaft splines are stuck in the bottom of the crank? Try jostling the flywheel back and forth while pulling down on the foot. Use some anti-sieze on the drive shaft splines when you reinstall. Shift shaft splines could be sticking I suppose, use anti-sieze there too on reinstall.

Or maybe the water tube is sticking in the pump housing, try jiggling the foot around while pulling it. Use some vaseline to lube the tube when you reinstall.

Have you had the foot off before?

no i have never had this one off.. its giving me fits
 

marineralec

Cadet
Joined
May 3, 2011
Messages
14
Re: 70hp lower unit drop. Shift linkage???

Did you resolve this and drop the lower unit ok?If not,I may be able to help,avoiding some of the pitfalls
 

jbakerinc

Seaman Apprentice
Joined
Jan 2, 2009
Messages
38
Re: 70hp lower unit drop. Shift linkage???

Nope. been busy but am going to this week. How many bolts total do i need to remove???
 

ajgraz

Lieutenant Commander
Joined
Mar 1, 2010
Messages
1,858
Re: 70hp lower unit drop. Shift linkage???

Nope. been busy but am going to this week. How many bolts total do i need to remove???

Remove bolt holding anode (from the top, at the rear of the foot); that one is 1/2" IIRC. Under the anode is a thin (jam) locknut (from the bottom); that one is 9/16" IIRC, and being a thin jamnut likes to break if tightened too much--I have some spares if you need one. Then there is another 5/8" locknut (from the bottom) right in the middle of the cavitation plate. Then there are two 5/8" locknuts, one on each side of the foot (get these from the sides); do these a few turns on one, then the other, then the first, etc. Don't lose any of the washers, they are very hard to find replacements for.

That should be it. Reverse order for reinstall.

If you got them all and the foot still drops only 1/2", my guess is the driveshaft splines are stuck in the crankshaft. Sounds crazy and dangerous and will destroy the impeller (which you are replacing anyway), but you can try this...drop the foot as much as you can while leaving those side locknuts on a few threads, then key on a few times (in neutral of course, not to start but just to engage the starter), this may free up the stuck splines.

Without cracking the aluminum of course, don't be afraid to pry on the mating surfaces between the foot and the midsection, the top part of the foot is not sealed from water anyway; the LU lube is in its own sealed section lower in the foot.
 

jbakerinc

Seaman Apprentice
Joined
Jan 2, 2009
Messages
38
Re: 70hp lower unit drop. Shift linkage???

yeah that sounds about right. I guess ill just have to man up and pull it off.
 
Top