![]() |
![]() |
![]() |
|
Boating Talk For discussion of everything related to boats and motors |
![]() |
|
Thread Tools | Display Modes |
|
#1
|
||||
|
||||
![]()
I have an old 1975 25 HP Johnson Outboard that is not running good.
It will run when it is idled up but at idle speed it has a bad miss and will kill. I have cleaned the carb and diaphram, new plugs, new points and condenser. Changed the fuel lines, new tank and hose and bulb. It has a lean/rich knob on the front . Here is a picture of the lean/rich knob and a leak where the motor splits in half. How do you set the lean/rich knob.(Tighten all the way and back out how many turns)? Will the leak in this area cause the motor to run bad? Does it have a gasket in this area? Is it hard to fix? |
#2
|
||||
|
||||
![]()
The pictures didn't work the first time.
|
#3
|
||||
|
||||
![]()
Usually these old motors have gas & have fire they'll run. If it has a bad miss may have a bad plug wire or fire jumping somewhere. Crank it in the dark & see if you see fire jumping.
As far as the lean/rich knob tighten then back out 1 1/2 turns & start from there. As far as the leak that could be your miss also. If it's getting water in the heads it will crack the head or a piston. that needs to be fixed! |
#4
|
||||
|
||||
![]() Quote:
It dont miss a lick when running wot only when idleing and will kill. There are small bubbles coming from the leak. Is this water or gas in this area? |
#5
|
||||
|
||||
![]() Quote:
1 1/2 turns out on the screw will be a good starting point also check the timing base plate you may have to bump up the idle timing just a little to get it to run at idle..also double check your your points gap I believe on this motor its right around .018 to .020, chances are is the timing is a little to low at idle, make sure you dont mess with the WOT timing just idle timing you can easily melt a hole in the pistons.. |
![]() |
Bookmarks |
|
|