Crying over lower unit

G DANE

Commander
Joined
Nov 24, 2001
Messages
2,476
I just got a 1977 4,5 HP, originally bought as I needed the lower unit for my 9,8 HP, but looking at it this little motor, it looks fine. I think I will fix it and let my 13 yo boy run it on his dighny. It has plenty of compression, and a spark that can send a cow to the ground, turning flywheel by hand !! I guess its only cleaning and rebuilding carb, and an impeller change, then its running. There was an old rusty spark plug in it, surface gap type. What is the correct spark plug. Will this model have any specific issues to check for ?? Its had the exhaust cover gasket replaced.
 

Paul Moir

Admiral
Joined
Nov 5, 2002
Messages
6,847
Re: Crying over lower unit

The spark plug should be a NGK BUHW-2 or a Champion (Q)L78V. Those are both surface gap plugs.<br />I'm not really very familiar with that engine though, so I can't help with your other question.
 

G DANE

Commander
Joined
Nov 24, 2001
Messages
2,476
Re: Crying over lower unit

Well, spring is on its way now, at last. So we cleaned the carb on the 4,5 and started it up in a bucket, let it iddle for 4-5 min. Needs a water pump job, I knew that. At first, no tell tale, later it only dribbled from it. I could have sweared exhaust gasses came out from the tell tale from start - later nothing. It didnt overheat. The only place I can think of should be exhaust water jacket - right ??? , better get it off and take a look - looks to be sealed with silicone only. This is a salt water motor -. no water on spark plug - wouldnt there be if cylinder leaked.
 

G DANE

Commander
Joined
Nov 24, 2001
Messages
2,476
Re: Crying over lower unit

Well tonight we were going to change water pump. But this lower unit decided to stay where it is. I've delt with difficult lower units before, but this one is tough. Is there anyone sitting with THE TRICK to get it off, we are lost here.
 
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