Thanks for the info on previous posts.I'll start by explaining what the situation is. I bought this unit with an '89 evinrude 120 v4. The boat and motor have been sitting for years. After cleaning the tanks, purging the fuel lines and using about a case of carb cleaner, we finally got this thing running. new plugs were installed. never had it on the water yet, seems everytime i think i may be ready, something problem rears its ugly head. For some reason, i am getting an ungodly amount of smoke and an intermittent miss during gradual throttle. as the motor runs, i can see the fuel level in the inline filter dropping, then the engine will cough and spit. no knowing much about marine engines, i am leaning towards an airleak in the fuel system. am i on the right track? while running, i can hold my hand on the primer bulb and feel it suck down (not alot but i can feel it pulse, new bulb too by the way) when the engine spits. i pulled the plugs and checked them and found only one to be dry. the other three are wet. fouled plugs or normal? i am assuming the excessive smoke is due to the fuel level dropping and the vro still pumping oil into the chambers. sound right or am i way off base? we have the lower unit in a barrel right now and after a few minutes of running there is oil on the surface of the barrel water. what is this from and is it normal? again, thanks for the advice it has lead me from an abandoned unit to at least this far in life. carbs kits are ordered and will be installed later this week. it cant hurt even if its not a solution the my problems.
You say your plugs are wet?only 3 and 1 is dry.that means that may be the dry cylinder could be running lean.the sputtering is a fuel problem.start with the simple things first.Make shore the valves in the primerbulp work it prevents fuel leaking back into the tank.Make sure the tank vent is not clogged.after you inspect the whole fuel line and can not find the problem it is time to rebuild the carbs. wouldnt be a bad thing to do because you dont want your motor to run lean.and when you are busy with the fuel line i would put a fuel water seperator between the tank and the primerbulp.but i'm not a mechanicgood luck.reeldutch
Truax...maybe since the engine set so long, the little rubber seals between the oil and gas chambers in the VRO pump have dried out and more than enough oil is being injected into the engine and not all of it will burn.Disconnect the oil line to the nipple on the engine pan and cap the nipple air tight. Mix a can of premix and run this in the engine and see if you still get a lot of smoke and oil on the water.Course, running in a drum can be decieving. If you where on the water, you may not see all that oil. Why not get the carbs rebuilt, decarb the engine, and get some compression readings after for future reference.Do you got good spark to all cylinders? The spark to each cylinder should jump a gap of at least 7/16" with a strong white hot spark. Just some things to look at.
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When in doubt...use the manual
Rayland, Ohio....Along the Muddy Banks of the Mighty Ohio River.
I have the same engine. If the primer bulb is collapsing, sounds like either the bulb valves aren't working right or you may have a restriction in the fuel line. Try removing the primer bulb and with the boat on a trailer, drop the end of the fuel line overboard and start a siphon. Fuel should siphon freely. If it won't, and the end of the fuel line is lower than the tank, you have some sort of restriction in the line. A friend told me his mechanic related a story of a customer of his who spent thousands of dollars over several years on repairs, only to find there was a leaf floating around in the bottom of his tank. Every once in a while the leaf would come close to the fuel line and get sucked onto the strainer and kill the engine. You always find what you're looking for in the last place you look!Good luck!
walker...not sure about recirculating system....not too familiar with marine engines...i relaced all the fuel lines from the bulb to the carbs. did find some cracked. that fixed part of the problem but it still coughs... will check the lines from the tamk to bulb next. would a cracked siphon hose or fitting cause this as well??
You say you went thru a case of carb cleaner. Did you actually tear the carbs down and clean them good? Recirculating system = look for small rubber hoses running from the side if the cylinders up to the front to the intake manifold. There would be one hose for each cylinder.
yes...we did tear the carbs down and gave a good soak and blew them out. there was an ungodly amount of varnish buildup as the gas was left in the carbs for years........there are no hoses as you mentioned so i would be safe in saying there is no recirculation