Johnson 70hp 2001 Tuning

luisdiaz

Seaman Apprentice
Joined
Aug 18, 2008
Messages
41
Hi. I just finished the rebuild of carburetors. The motor is starting fine and idle sounds good to me (outside the water with flush device). However if shoot the fuel hose fittings with engine starting fluid (as suggested by seloc manual) to check for air leaks it get the rpm's lower, which suggest to me there is a leak there and in couple of other places. What does not make any sense is that the hose and manifold looks new, also had tried to coupling them with the original clamp, tie rap and screw clamp. I believe I should just change the hose and manifold but I wonder if it is not just right to use that fluid for the test. Also I believe there should be pressure at this stage instead of vacuum because is just after the gas pump (but don't know). Any comments?
Also I still have to do the idle timing adjustment (with timing light). In the manual it says it has to be done in the water. It is not legal to run a boat with motor cover off where I live (Puerto Rico). So wonder how close or far (right or wrong) is it by doing it outside with flush device and motor in neutral.
know the wot timing as per seloc should be performed with a test wheel in a test tank, a tool that I don't have. Do I have any option? or How can I get the wheel?
Excuse the predicament and thanks in advance.
 

Benny1963

Lieutenant
Joined
Sep 17, 2006
Messages
1,476
Re: Johnson 70hp 2001 Tuning

joe reves method works.go to auto supply and get stainless fuel injection hose clamps they work great ,good uck repost after you time it and remember to subtract 4 degrees . from your timeing number
good luck bennyb
 

luisdiaz

Seaman Apprentice
Joined
Aug 18, 2008
Messages
41
Re: Johnson 70hp 2001 Tuning

Thanks David and Benny. Will try to go for it this week.
Regards, Luis.
 

luisdiaz

Seaman Apprentice
Joined
Aug 18, 2008
Messages
41
Re: Johnson 70hp 2001 Tuning

Shame on me, there were no air leak. I was spraying the engine starting fluid and the vapors were getting to the carburetors through the base air silencer entrance holes:eek:. Now I wonder if it was like that since the beginning. :confused: Sure will never know.
Still have to go trough the max. spark advance. Need to confirm if this procedure do fine with this motor model (j70plsis, 2001).
Thanks again
 
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