"66 MERC 650 LOWER UNIT

[hoss62773]

FIRST TO START OFF, THANKS LADDIES FOR THE CARB HELP. ENGINE IS RUNNING OK THOUGH WITH A LOT OF SMOKE. <br />THE TELLTALE LOOKS GOOD, BUT THERE IS ALOT OF WATER PUMPING OUT THE HOLE FOR THE GEAR SHIFT IN THE LOWER UNIT. AFTER DROPPING THE LU, IT APPEARS THAT THE PREVIOUS OWNER REPLACED A SECTION OF THE WATER PUMP HOSE WITH SOME COPPER PIPE AND WHAT LOOKS LIKE AUTOMOTIVE A/C HOSE. NONE OF THE CONNECTIONS ARE CLAMPED. THE COPPER PIPE IS INSERTED INTO THE OLD WATER HOSE TO THE HOUSING, IT IS THEN INSERTED INTO THE A/C HOSE WHICH GOES UP TO THE FITTING IN THE DRIVE SHAFT HOUSING.<br />IT ALSO LOOKS AS THOUGH THE WATER PUMP HOUSING HAS A GAP AT THE GASKET. BUT I DON'T HAVE FEELER GUAGE TO TELL FOR SURE. BUT SOMEHOW WATER IS GETTING INTO THAT FORWARD CHAMBER AND COMING OUT THE TOP AROUND THE GEAR SHIFT ROD.<br /><br />I AM ALSO GETTING, WHAT SEEMS TO BE EXCESSIVE, EXHAUST OIL COMING OUT AT THE PROP SHAFT. <br /><br />I SHOULD ALSO NOTE, THAT WITH THIS MOTOR, THERE IS A 5" EXTENTION ADDED BETWEEN THE LOWER UNIT AND THE MID SECTION. THERE IS AN EXTENTION FOR THE EXHAUST PIPE, GEAR SHIFTER AND ALL THE BOLTS AND STUDS ARE LONGER THAN STANDARD. I'M GUESSING THAT IT'S TO MAKE IT A LONG SHAFT. <br /><br />SO MY QUESTIONS ARE: <br /><br />1: CAN THIS WATER PUMP HOSE BE REPLACED FOR THIS YEAR MOTOR? OR CAN I PUT CLAMPS ON THESE JERRY RIGGED CONNECTIONS TO SEAL THEM OFF? <br /><br />2: HOW MUCH DAMMAGE COULD HAVE BEEN CAUSED IF THE WATER PUMP HOUSING IS NOT CLOSED PROPPERLY?<br /><br />3: HOW MUCH OIL IN THE EXHAUST IS TOO MUCH? <br /><br />AND ONE SIDE NOTE, WHEN I BOUGHT THIS MOTOR, THE PROP WAS CHEWED UP BAD AND THE SKEG IS MISSING ABOUT 2.5 INCHES. PROP SHAFT SEEMS STRAIT, AND WHAT'S LEFT OF THE SKEG IS BENT SLIGHTLY. I'M PLANNING ON REPLACING THE PROP SHAFT SEALS WHILE THE LU IS OFF.<br /><br />HE GAVE ME ANOTHER LOWER UNIT, BUT IT'S MISSING SOME SCREWS, HAS A LONGER DRIVE SHAFT, SHORTER ATTACHMENT BOLTS AND IS PARTLY FULL OF SAND. IS IT POSSIBLE AND/OR WORTH THE EFFORT TO SWAP OUT THIS LOWER UNIT HOUSING WITH THE ONE WITH THE BROKEN SKEG?

 

[Laddies]

Re: "66 MERC 650 LOWER UNIT

I think part of the problem with the w/tube is some one has lost the extention tube that came with the kit, I am not sure if the kits came with a exhaust est. or not, you might ck twin citys for parts for it or make your own ext out of copper pipe and a coupling. Are you running at 50 to 1 mix. if not that could be your smoke. The other unit sounds like a unit off a long shaft engine a I cann't remember but it seems like back then the castings were differant numbers, you can probably get it welded while apart but it probable won't hurt anything the way it is

 

[hoss62773]

Re: "66 MERC 650 LOWER UNIT

thanks again there laddies. does that twin cities have a website? tha exhaust gasket for the extention is blown and i'm getting exhaust coming out everywhere. I mixed 2 seperate 1 gal mixes for 50:1 the problem is on the oil mix, for 1 gal fuel use 3 oz oil. 2 gal fuel, use 5 oz oil. so i'm sure its a bit rich since i have 6 oz oil in there. will adjust and let you know. <br /><br />do you think the loose fittings this guy made would be enough to send water throughout the whole LU? there was quite a bit of water coming out the shift shaft hole. I'm opening up the water pump anywhay as there is a bunch of sludge in the tube. I think this guy hit a huge sandbar in the Missouri river. is there any hidden places i need to watch out for in cleaning this out? <br /><br />procrastination has been my biggest enemy on this one, summer's here!!!!

 

[Laddies]

Re: "66 MERC 650 LOWER UNIT

Usaaly that much water comes from a long shaht engine on a short shaft boat, is the cavitation plate level or just above the bottom of the boat. If the engine is to deep it will cause all kinds of weird things to happen

 

[hoss62773]

Re: "66 MERC 650 LOWER UNIT

the engine is running on a stand in a bucket at the moment. the bucket was filled just above the cavitation plate to the second of 4 vent slits in th LU

 

[Laddies]

Re: "66 MERC 650 LOWER UNIT

Then its got to be the w/pump pushing the water around the shift shaft and don't worry to much about the smoke then running a engine that way

 

[hoss62773]

Re: "66 MERC 650 LOWER UNIT

thanks again, you've been a huge help with this one. gonna try and get that w/pump hose sealed better then get it to the water.

 

[hoss62773]

Re: "66 MERC 650 LOWER UNIT

after taking off the water pump assembly, the drive shaft hase some corrosion at the lower seals. should this area be smothed out before proceding with seal replacement? or will it make the DS too thin? it's fairly minor but rough to the touch.

 

[Laddies]

Re: "66 MERC 650 LOWER UNIT

The seal area must be smooth, if you can't clean it up you may have to install a seal sleeve to correct it

 

[hoss62773]

Re: "66 MERC 650 LOWER UNIT

i'll get on it, any tricks to keep flaking rust from going into the bearings?