prop change color

[bobimo]

1999 200 hp efi mercury s/n0g866278, put a new power head onlast year and while trying to get it to run had a fuel problem, it was dumping fuel out the exhaust, noticed the prop ( stainless) had change colors to look kike it was bronze
fixed the fuel problem and cleaned the prop. no problems until last week noticed the prop had changed colors again, boat run fine, no exces gas usage, any suggestion, thank bob

[lpugh]

Certain areas on the prop or all areas?
Combination of the water you run in and electrolysis's I suspect

[bobimo]

it is the whole prop and i did not seen this problem until the water started to cool off, less than 60 degrees.
bob

[JOE54]

is this a MERCURY propeller , clean and check all grnd straps , make sure continuity washer is installed on prop

[EuropeanAM]

is this a MERCURY propeller , clean and check all grnd straps , make sure continuity washer is installed on prop

^^^^^ +1

Be interested to see a picture.

[bobimo]

prop is 25 tempest plus, what and where is the continuity washer, i have run this prop for 14 years in the same water with no problems
bob

[JOE54]

continuity washer (823511 ) is a washer that goes between drive adapter and prop your may or may not have one provided they help grnd prop to gearcase for corrosion protection a possibility , i had a customer with this exact problem many years ago like 20 , my mind just wont let me remember the cure , that was thousands of engines ago , im wanting to say it was onboard batt charger fault

[EuropeanAM]

How much time does the boat spend in the water?

Continuity ground cable still intact at port-side (lower) engine mount bolt/nut?

[bobimo]

all ground strap good, checked conunity between prop and ground on starting battery less than .5 ohms, boat is only in the water when it is in use, same lower unit same prop and washers for 14 years.
bob

[leonreno]

Any new electronics installed on the boat before this started happening? When in use, are we talking in and out the same day or is it in the water for two, three days at a time? What boat is it one?

[EuropeanAM]

Power Poles, Trolling Motor changed, new batteries installed, jackplate, battery charger (or on the fly setup of some sort)?

[bobimo]

nothing new on boat, boat is a ranger 518, I cleaned prop and going to run it to see if the prop changes color again.

[JOE54]

report back please

[bobimo]

found water in lower unit, waiting on parts, will update when motor is ok to run
bob

[JOE54]

uh oh good luck

[bobimo]

repaired lower unit, ran boat for about 30 minutes no problems prop did not change color
bob

[JOE54]

that when in my memory bank for sure

[EuropeanAM]

Me too....