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offshoreed
08-01-2005, 07:43 PM
i have a 540 with a 250 b&m blower. i am running 50 weight oil. after one days running the oil color is on the brown side . i wonder if some fuel could be going threw or ? its not water. need help.
LGCDEVIL
08-02-2005, 05:42 AM
Same here. N/A 580 ci. Oil temps 190-240 on 20/50. Oil is still very thick.
LGCDEVIL
08-03-2005, 10:38 AM
Anyone??
eliminator777
08-03-2005, 11:05 AM
:D usely it's fuel I run 70wt in my motor and after 1 running day it gets like that In my case I'ts the 1471 blower it makes lots of wind :D
Robbie Racer
08-03-2005, 04:18 PM
i have a 540 with a 250 b&m blower. i am running 50 weight oil. after one days running the oil color is on the brown side . i wonder if some fuel could be going threw or ? its not water. need help.
It sounds like fuel is getting past the rings into the oil. How many hours do you have on the rings?
offshoreed
08-04-2005, 04:15 PM
i have no more than 40 hours on it. it could be getting some past. i was also thinking that the oil is getting hot. i don't have a oil temp gauge. may have to do a comp test, but the motor runs real strong. the oil cooler i am using is a olson hooked up straight from the out drive then to the sea water pump.
motor is in a AO if that matters.
Robbie Racer
08-04-2005, 04:32 PM
Excessive oil temp could cause that problem too. Do you run synthetic or regular oil? I use Mobil 1 that is rated around 400 degrees if I remember correctly. I think regular oil breaks down somewhere around 270, I think. Before I had my motor refreshened last winter by Larry Peto, I was getting a lot of fuel in my oil which turned it dark (and it was also using a lot of oil) only 35 hours after it was built by the original builder. So far, I have 42 hours on the latest rebuild and it's still not using oil or turning dark nearly as early as it did before. I did change it after 30 hours and it was a little dark by then.
djdtpr
08-04-2005, 06:48 PM
I am thinking that it is the oil you are running.I think if you went to a fully senthetic like mobil one your problems would be gone or at least not as bad.
offshoreed
08-05-2005, 07:54 PM
thanks guys i will try that. i ran it tonght and it still ran good. the moble 1 may do the trick, i will let you know.
offshoreed
08-09-2005, 07:19 PM
after meeting with a carb expert today, looks like i have fuel in the oil. the two 750's are being rebuilt and new oil put in and we will see if the oil turns brown after that. he also said that my wide open throttle was not opening up all the way. hoping to see the triple digit mph. maybe prop change to.