1973 50hp merc. water and gear issues

[kclanier]

Ok I relaced my impellar and reinstalled the unit. Still no water moving I have tried rooting out both ends of the hose and pressured water and I can't get the gearing lined up. Could it be a Thermostat " If so where is it, how do I get to it, and where can I get a replacement or does it even need to be replaced? Can it just be removed.
The gearing, How do I get every thing lined back up? Forget where they were when it came off. I have tried move evry thing around. It is in constant reverse HELP!!!!!!!!!

 

[wiggles6983]

Re: 1973 50hp merc. water and gear issues

Were you having a problem with water flow/pressure before replacing the water pump? I recently had a similar problem, and the powerhead mounting base gasket was leaking (water was being pumped up to the adapter plate and leaking straight into the exhaust)

There is a small brass plug that can be removed to see if water is coming up to the powerhead (also used for a water pressure gauge).

As for getting it to line up, if the lower unit is in reverse, slide the shift linkage to the rear of the motor, this should be close for it to line up. If the driveshaft doesn't line up either turn the prop or flywheel until it does.

 

[kclanier]

Re: 1973 50hp merc. water and gear issues

I need more details

 

[j_martin]

Re: 1973 50hp merc. water and gear issues

I need more details

Best money you could spend, get an OEM maintenance manual.

hope it helps
John

 

[tmcalavy]

Re: 1973 50hp merc. water and gear issues

You have a 73 Merc 500...no thermostat. Make sure the impeller is keyed to the driveshaft, the key can slip out on you. Doesn't matter if you drop the foot in F or N, but F is easier in my past experience with 500's. When the foot is dropped down, you'll find the shift shaft up front, the little stob that sticks up. You have to turn this gently with a pliers until the gears slip into F...assuming you dropped the foot in F, has to be in N if you dropped it in N. Here's the aggravating part...takes patience getting it lined up so it doesn't slip when you mate the foot back to the leg. Take your time...may have to reset the shaft/stob a few times before it takes pity on you and meshes together right. Don't get impatient and crank on the shaft...don't ask me how I know this, long expensive story. Have a bud come over and help you, enjoy a tasty beverage while you're doing this. Make sure the water tube is lining up and seating right, too. Great outboard you have...mine ran like a striped ape. Invest in a manual, it makes the maintenance much easier...the Merc factory manual, see them often on the auction site.