Ryden
New member
I just bought a presumably 76-77 Mercury 500 in parts and need some advice.
It ran god and strong until last summer untill the tell-tale stopped squirting water. The previous owner took it to a shop that put in a new impeller but that wasn't enough.
Turns out that somebody has repaired it with a piece of plumbers copper pipe and clear silicone caulk
At that point the shop said it would cost to much for them to lift the power head and fix it, but that he could do it himself over the winter and sourced him a used coolant pipe to put in.
Apparently this wasn't the only do-it-yourself project he had on the farm, there was a seized tractor, a small saw mill that didn't work, a chainsaw without spark and various other things.
SWMBO declared that non essential repairs was done on his own peril and he decided to unload the outboard.
Compression was 110/110/120/???, I couldn't get a good seal with the comp meter on no 4 cylinder so I took a chance it was good to
So what I got for a modest sum was:
- A late 70's short rig Mercury 500 Thunderbolt with lower unit detached and unreadable S/N
- New spark plugs
- A lower unit for same with new impeller and a prop in god nick
- Control unit with cables
- A 6 gallon tank with those
- The old copper pipe
- A pre-loved coolant pipe with rubber seal
- Some plastic bags with zink anode and nuts and bolts, all nuts and washers held together with cable ties
- The name and phone number of the outboard tech who did the original job.
It should be everything I need to fix it.
I flipped the OB up side down and had a peek down the rig .
Next to the exhaust pipe I could see a hole where I presume the coolant pipe should attach to the power head.
At this point I thought that all I had to do was insert the pipe into the hole and reattach the lower unit and that would be it.
However the hole is larger than the pipe and I can drop the pipe a good bit into it.
There seems to be something missing.
It ran god and strong until last summer untill the tell-tale stopped squirting water. The previous owner took it to a shop that put in a new impeller but that wasn't enough.
Turns out that somebody has repaired it with a piece of plumbers copper pipe and clear silicone caulk
At that point the shop said it would cost to much for them to lift the power head and fix it, but that he could do it himself over the winter and sourced him a used coolant pipe to put in.
Apparently this wasn't the only do-it-yourself project he had on the farm, there was a seized tractor, a small saw mill that didn't work, a chainsaw without spark and various other things.
SWMBO declared that non essential repairs was done on his own peril and he decided to unload the outboard.
Compression was 110/110/120/???, I couldn't get a good seal with the comp meter on no 4 cylinder so I took a chance it was good to
So what I got for a modest sum was:
- A late 70's short rig Mercury 500 Thunderbolt with lower unit detached and unreadable S/N
- New spark plugs
- A lower unit for same with new impeller and a prop in god nick
- Control unit with cables
- A 6 gallon tank with those
- The old copper pipe
- A pre-loved coolant pipe with rubber seal
- Some plastic bags with zink anode and nuts and bolts, all nuts and washers held together with cable ties
- The name and phone number of the outboard tech who did the original job.
It should be everything I need to fix it.
I flipped the OB up side down and had a peek down the rig .
Next to the exhaust pipe I could see a hole where I presume the coolant pipe should attach to the power head.
At this point I thought that all I had to do was insert the pipe into the hole and reattach the lower unit and that would be it.
However the hole is larger than the pipe and I can drop the pipe a good bit into it.
There seems to be something missing.
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