Old Mercury disease for real?

[bartman49]

I recently brought my mid '70s 85 hp mercury pump in to the LBS for diagnosis of rough running condition. They told me it has "old mercury disease" which means that the insulation of most wiring is shot and that it's not worth repairing. Is this a well known condition and is the LBS assessment of repair feasibility correct? What are the options for completely rewiring an older mercury outboard? I'm bummed because I just bought this boat for what I thought was a good price, but looks like I been took!
Thanks
Bartman49

 

[studlymandingo]

Re: Old Mercury disease for real?

replace the wiring​

 

[glockbwb]

Re: Old Mercury disease for real?

I'm very new to boats and outboards about 4 days to be exact. And I had the same problem with my motor it wouldn't even start all the wiring was corroded and insulation cracked. I spent a couple of hours and replaced every piece of wire on the boat. On the motor I cut all the wires back as far as possible and soldered and shrink tubed everything. It runs great now the only problem I had was with the condenser it is a sealed part and was corroded to the point of no repair.

 

[Clams Canino]

Re: Old Mercury disease for real?

See Ebay item # 160132693063 It will solve 9/10 of any wiring problems in that motor.

-W

 

[daveswaves]

Re: Old Mercury disease for real?

There is an old mercs disease but it affects the owners. There is a group therapy forum for those severely afflicted.

 

[OldMercsRule]

Re: Old Mercury disease for real?

There is an old mercs disease but it affects the owners. There is a group therapy forum for those severely afflicted.

"Old Mercury disease" Yep I got it allright! Wires, fuel lines, filters, fuel n' water pumps!! That's usually what it takes to resurect 'em: then YOU WILL HAVE THE DISEASE I HAVE! You'll luv 'em!! They are cheap, 'cause many out there just view 'em as a spendy black boat anchor. Don't try the float test!!! I collect 'em when I can, n' revive 'em if they have even compression n' not too much play, n' the lu checks out. Then after I'm done playin' with the wires, lines et al, I hit the key n' boom! Take a spin around the lake or bay huntin' anything of similer horse power n' weight n' see who rules? My bet is the Merc will!! I don't care if yer talkin' at the crank or the prop those old girls fly!! N' they're purdy too! My $.02 JR

ps: don't the Johnnyrudes wires corrode on the old ones too, or am I dreamin' ?

 

[billybones]

Re: Old Mercury disease for real?

A mid 70's? Is it old? what disease? IT is old. It spends all its time out doors in a wet condition. Mostly abused and uncared for. Hot as heck when running at full throttle. Then chugged at idle for hours on end while looking for a fish. It amazes me that when buying a boat with a 30 year old motor it is supposed to be in top running condition... LOL.

 

[Scaaty]

Re: Old Mercury disease for real?

Yep, after 37 years, and the insulation used then, well...about the simplest thing to upgrade, and while at it, spruce up what else needed, and ya got ya a good old Merc...

 

[Unarmed]

Re: Old Mercury disease for real?

heh, my 2 problems with this boat are 1 fuel pump, and 2 wiring. the 2nd I am gonna start fixing asap. the first once I have enough for the #1 sparkplug wire and boot (because I have to order the fuel pump kit from the same place). and I know what was wrong with the motor before the wires went, because it was my fathers.