Where the hose attaches at the intake manifold / block is listed as a nipple and not a " check valve "------------It simply sucks in any spillage from a flooding carburetor and is a " safety item " nothing else.
Thanks, that makes sense.
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Where the hose attaches at the intake manifold / block is listed as a nipple and not a " check valve "------------It simply sucks in any spillage from a flooding carburetor and is a " safety item " nothing else.
The hose and primer bulb appear to be in good shape. I did just replace the ends because they were cheap. When I pump up the primer bulb it gets hard and there are no apparent leaks in any of the fuel lines or connections. I have also tried swapping lines and tanks with my kicker motor and it had no affect. I am taking Wednesday off work and going fishing so I will see how it runs then with my most recent changes and adjustments. I will also try adjusting the timing pickup point and see what that does. If it still wants to die when I accelerate my next thing to try is obtaining some 75HP carbs with adjustable needles.I had similar problems with an '83 70hp evinrude. Turned out to be the fuel line from the tank. The squeeze ball had a crack in it. Also replaced all fuel lines with the new "ethanol resistant" hose as it was all cracking and disintegrating from the new ethanol gas.
Mine ain't.The 3 cylinder OMC is a wonderfull motor.-----They built thousands and thousands of them.
Thanks for the info. This just might work.Turning that mixture screw counterclockwise will indeed richen up the mixture...
With your wide open being 5000 rpm your prop pitch should be ok.... but since you have tried everything else, maybe a 17" prop may also be worth a try..
The 17 should put your wide open to close to 5500rpm and this may just be enough to lessen the load on the motor to get you over the point bogging down..
I have already replaced all the hoses, clamps, zip ties etc associated with my fuel and oil system. My fuel pump is a VRO pump and I dont see any metal screen on it. There is a plastic filter with a plastic screen for the fuel and a long conical screen thingy for the oil. I will however double check everything for leaks.DON'T GIVE UP!!!!
I spent three years troubleshooting the EXACT same problem on my 1982 75 hp. I did EVERYTHING you did and more. Finally, one night after tilting the engine up with the cover off I noticed fuel dripping from the round connector that houses the metal filter screen on the fuel pump body. It turned out 25+ years of fuel and heat had warped the plastic and was allowing air to be sucked in, leaning out the engine. I put two zip ties over the connector and it works perfect.
Amazing how the simple, cheap things drive us batty. Check yours out!!
Start your own thread. This one is 6 yrs oldHey All,
I have 1985 70HP Johnson. Revs are perfectly fine at idle, good compression. When under load, it takes a very long time for acceleration. Very gradual. Barely any throttle response. What you thinking, fuel flow in carbs or something else?