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Mercury Vro 50 pluG fouling

S

Scotauto

New member
I have a mercury vro 50 from 1985, compression is good and even on both cylinders but no matter how I start up (in workshop/not water) it fouls the plugs with oil very quickly. There is a fuelpump on the right side of the engine (if looking at boat from the rear) which has a red dial/switch on it. Should this be on full or not? I can't seem to get it to idle and can only keep it running if I hold the gas cable linkage open quite a bit. The gas gear lever is not attached at the moment. Any thoughts? If I remove the oil line for a little while the plugs look normal again. Obviously it's fouling the plugs with too much oil but is this because of lack of fuel. I've read a load about bypassing the Vro and am considering this also.
 
Mercury or Johnson ?????------------------The thing with the red lever is the primer ( replaces choke ) used in starting .-------------Lever should be straight ( in line with ) with the valve body.The primer operates when you push the key in while cranking the motor to start.---------That item is not a fuel pump.-------------------------Proceed with caution !!!!
 
hi thanks for your reply.Sorry my mistake... It's a johnson engine. When you say straight do you mean left to right straight or up and down straight? It's definetly working as it injects no fuel when closed. Where is the fuel pump located? I not very experienced with this type of engine. Can I run in the workshop without overheating it? or does it need to be in water.
 
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You must supply water to the waterpump !!!-----------if you have run this motor " dry " you have ruined the water pump and it must be replaced.---------------The " red lever " operates the valve manually.---------It must be parallel to the valve body.---------------------Follow the fuel line coming into the cowling to find the fuel pump.---------------------Visit --------------shop.evinrude.com-------------------To become more familiar with the parts on your motor !!
 
yes I guess your right. I'll change it. In the heat of the moment I just wanted to get it running and probably got a bit carried away :) so replacement is the only answer. The engine wasn't firing when I got it and after I fixed that wanted to check the engine could run. I'm not really happy with the Vro system so I think I'll be removing that too. oh well the new gear/gas cables arrived today. They fell apart in my hands when I removed them !!
 
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