Lower unit removal

eliassen

Cadet
Joined
Apr 3, 2004
Messages
14
Having very good results when I earlier have begged for help, I try again: The water pump on my Evinrude 6 hp 1976 (B66A67) stopped to work. That means that I have to open the lower unit for the first time. According to my Seloc-book, I have to rotate the flywheel until a pin in the upper driveshaft is aligned with two slots in the upper portion of the exhaust housing.<br /> I must admit I don't understand anything of this. Could someone please give an amateur a better explaination. Where is the pin located? Should this be done before I drop the lower unit an inch to remove the bottom bolt? Do I need to remove any screws in the upper end of the shaft? Has the little rubber plug in the middle of the shaft any connection with this operation?<br /> I would be very grateful for answers from the experts!
 

rodbolt

Supreme Mariner
Joined
Sep 1, 2003
Messages
20,066
Re: Lower unit removal

hello<br /> youll never see the pin. lukily it breaks off fairly easy. the pin holds the lowere crank seal assy in place. its an odd setup but it works. <br /> do dissconnect the shift linkage ya have to remove the 4 lower unit mounting bolts and drop the lower down while moving the shift lever. the dissconnect block will be visible thyen at the fwd end of the case. its easyist to use a 1/4 drive socket assy. problem is thats about the point the roll pin gets sheared. its easy to replace aand I purchase one with each pump kit I buy.<br /> the pin will only fit through the exhaust housing in two positions. take care not to break it at reassembly. the pin is located about 2 or 3 inches down from the top of the driveshaft. I dont care how the flywheel is rotated you will never see it until the drive shaft clears the housing on removal. this is only appicable to a 6hp OMC manufactured engine. sometimes the over seas stuff is somewhat different. can you describe the rubber plug location better ?<br /> and a picture of the powerhead would be very helpful.
 

OBJ

Supreme Mariner
Joined
Dec 27, 2002
Messages
10,161
Re: Lower unit removal

The pin your are mentioning is a small spring pin which goes through the drive shaft. It holds the upper drive shaft seal in place to the bottom of the engine block along with a spring and washer. The seal assemble will not come out with the drive shaft because it sets in a cup cast into the midsection. The cup has two slots for the pin in the drive shaft to pass through.<br /><br />After removing the bolts holding the lower unit to the midsection, let the lower unit drop. Unless the pin is lined up, the lower unit won't drop far. Gently pull on the lower unit while turning the flywheel. This will turn the drive shaft. You will feel it when the pin is lined up with the slots and the lower unit will drop a little more. Now disconnect the shift rod connector and remove the lower unit. The pin will have to be removed from the drive shaft so the impeller can be removed. Just tap it out with a small punch and hammer.<br /><br />If you shine a flashlight up into the midsection, you will be able to see the slot and it's orientation. This will help with reassembly.
 

eliassen

Cadet
Joined
Apr 3, 2004
Messages
14
Re: Lower unit removal

Thank you very much, both of you - it seems that it was easyer than I thought (well, I haven't looked at it yet....).<br /> I guess the little rubber plug is of little interest, but I'm curious: It's 1/2 inch in diameter and placed on the flat side of the shaft, midway beetween the powerhead and the cavitation plate.
 

eliassen

Cadet
Joined
Apr 3, 2004
Messages
14
Re: Lower unit removal

Forgot to ask: I have a long shaft, is the shift disconnect over or under the extension? And: If I'm not to able to lower enough to get to the shift disconnect coupler, I understand you right that I can use force and break the pin?<br /> Again much obliged for an answer.
 
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