Motor problems

[eyechaser99]

I had my 2 cycle motor serviced and they put a new seal and impeller in it and it still leaks gear oil in the propeller. I also had a new hose for the gas tanks and for some reason after a while the ball goes empty and my motor kills on me. Any suggestions about what I can do to solve these issues?

[Surface Tension]

Are you venting the gas tank? Can you squeeze the bulb back up and run the motor again?

About the leak, if you payed to have a seal replaced and it still leaks the shop should take care of it.

[eurolarva]

If your new primer bulb and hose came from walmart toss it and get a decent one from a mercury dealer. The walmart ones work sometimes. They have crappy check valves in them. Could be you hooked it up backwards too. Might not hurt to check the fuel pump diaphram for a crack or hole.

If the seal they replaced was the prop shaft seal located on the bearing cage your problem could be the prop shaft itself is worn. fishing line gets caught in them and can create a real mess. What year and make is the motor?

[eyechaser99]

I had it serviced by a Mercury dealer and took it back to them and they seemed not to find anything wrong with it. I got the hose from them too and put it on the tank. I have tried pumping the ball but it seems to get empty fast and Id have to do it almost every second. They told me that it was from not running the oil out of it before I leave the lake and I have tried that still my propeller is full of that gear oil. I had fishing line in the propeller and they shoulda got it out when they put the new seal and impeller in right? That dealer has made me mad from by putting in different spark plugs than what I get and I have replaced them with the champion brand like in my Mercury book. They said NKG plugs are what Mercury is going to now. I have a older Mercury motor, what can I do to try to solve the leak by myself?

[eurolarva]

What size is the motor? I recommend going to Iboats and posting this in the mercury forum. Lots of knowlegable people there who will be able to help you. One way to find the leak is to remove the upper vent plug and submerge the lower unit in water then try and blow a few psi of air into the vent hole. This can be done with a rubber plug and a basketball needle. Look for where the bubbles come out and that is where the leak is. Yes they would have removed the fishing line however I have seen where fishing line wrapped in there has caused the propeller shaft to wear down at the seal so the seal wont seal anymore.

Are the spark plugs gapless? The NGKs gapless plugs are less prone to fouling then the champions. Also the use of synthetic oil helps prevent fouling as well. I dont know your motor however if your priming bulb does not get hard and there is no air leaks in the hoses it sounds like your fuel pump has a hole in it.

[eyechaser99]

I used the NGK ones at first with Amsoil synthetic and it still stopped on me. Should I wrap black tape over the hose and see if that works?

[eurolarva]

Does the motor idle and run okay? You mentioned it was taken in for the impeller and gasket replacement. Was this gasket on the water pump? Take a whiff of the oil you see leaking down by the prop. Does it smell like gasoline or lower unit oil. Lower unit oil stinks worse then Northerns. It has a destinctive order that is not pleasant. It could be unburned oil and gas mix draining down the motor leg and coming out the exhaust holes on the lower unit. What is the make and model number of the motor and the horse power?

[eyechaser99]

Its a 1980's small hp Mercury. How do you get rid of the unburned gas and oil if thats it? I tried running around the lake fast before I go in and it still did it. I put the old hose on and will try it.

[eurolarva]

I am pretty much a force and chrysler guy. The mercury forum at iboats can probably help you better. Your motor has a reciruilation system in it that has a fuel screen that is probably plugged. Basically gas hits the hot cylinders and condenses and is not burned. This gas goes through a recirulation system to be either reburned or just dumped back into the lake. Because yours is circa 1980 it is probably reburned. One of the most common reasons for this happening is carbon build up in the motor and gas is not burned as good. The motor should be decarbed every season. I do it with seafoam in my gas and every other season I buy a can of sea foam deep creep and fog it when it is warm and let it sit for a couple of hours then restart it and let it run wide open for at least 15 or 20 minutes.

I am not familiar with mercs fuel sytems but I would guess you need to decarb and then find the recirulation screens and clean them and check any check valves in the reciruilation system. I would then switch to NGK plugs and go to a synthetic oil that is TCW3.

[Surface Tension]

If its leaking gear oil its going be clean oil, thick and with no gas smell.

What color is the oil leaking from your lower unit and does it swell like gas. You have to determine this first or you'll be chasing your tail.

Since you brought up the fuel line that won't stay primed plus the film on you prop I'm thinking you have a float setting or mixture setting thats dumping gas. You should be able to pump it up the bulb and it should stay hard. Do this on land with the motor down in position and not running. If you can keep squeezing the bulb and it won't firm up you have a problem somewhere. It could be your pushing gas through an inlet valve thats not shutting the gas off when the bowl fills. Either that valve is no good, the float is bad or improper float setting. Other reason why the primer won't fill is the hose is on backwards or the primer bulb is bad or the drop tube in your tank is rotted. So figure out if the problem is in the carb or other areas I mentioned first.

If your trying to burn the gas out of the carb remove the gas hose and run the engine at the dock till it quites then restart with the choke on till it quites again.