Beating a Dead Horse. To Block Off or Not to Block Off Mercury Oil Injection

[Capnmoench]

I sold my EOI kit on The Hull Truth to a guy there. I told him it's not proven and was honest about not knowing it's dependability. Well, he took it off of my hands. I get back into cell service from camping and get a string of texts that it's only working intermittently. Also, I noticed that my warning module was faulty when I installed the rebuilt powerhead and all of the sudden I have beeps when I turn the key on. The combination of that and the intermittent pump brain was most likely the cause of my meltdown. All parts eventually fail. The less parts you have, the lower the chances of failure. I'm really glad I didn't slap that kit on my motor.

[David - WI]

There is an adjustment on the oil inj pump to raise or lower the amount pumped. The pre mixed tank method sunkist described above is how to allow safe adj of it.

I'm not sure if that's correct or not.
On snowmobiles (using the same style Mikuni oil pumps) the adjustment only appears change what throttle position you make the switch from 100:1 to 50:1 (or whatever the particular ratios are)... I've taken a couple apart and compared them. To increase the amount of oil, I had to install a pump from a bigger motor.

[XstreamVking]

The throttle link arm that connects to the pump goes to a cam of sorts that can be adjusted by loosening the screw and re-positioning the cam's position. It has "normal" marks on it. I have re-set the amount pumped by using a graduated vial collecting the oil dispensed and running the motor on a pre mixed can. Merc has specs of what should be pumped over a certain time. It is crude, but works.

[Glastron1987]

My 1988 XR4 oil injection system is still working. My rpms rarely get up to 6K. I like not having to mix the oil and gas.

Will let you know if it lasts another 29 years.

[NC 1750XLVEE]

One thing to consider. If i understand correctly. The oil inj pump is just like a hydraulic pump and the lever increases oil flow. To flow more oil would require more torque (although we're talking very small amounts) to rotate the pump shaft. So at an idle its pumping a tiny amount of oil hence lease torque required. Increase throttle, the linkage moves and "strokes" the oil inj pump creating a greater torque load on the pump drive. If there is a defect in the oil pump drive it should slip or shear under a higher load demand and maybe not slip or shear under a lighter rotational. I took my injection off.

[LakeFever]

My first V6 Mariner has OI still. Its an 88 as well and seems to be working fine. Super low hours on it and I have planned on deleting it but I havent even had it out yet this year. Too busy so I'll be running it as is when I do take it out. I love the tank size I can put 6 quarts in there and run for days

[KIRCHNER]

My first V6 Mariner has OI still. Its an 88 as well and seems to be working fine. Super low hours on it and I have planned on deleting it but I havent even had it out yet this year. Too busy so I'll be running it as is when I do take it out. I love the tank size I can put 6 quarts in there and run for days

PRE-MIXING IS A ROYAL pain in the a,, not to mention the MESS. MY 220 1987 oiler still pumps just fine. gas up and go. i will never remove my oil pump. its not for racing.