1994 Johnson 120 TLERC
Noticed my engine seemed to be clicking loudly at idle on the water and I think shook a bit more at low rpm than normal and maybe a bit sluggish. I never got an alarm.
Brought in home and started it on the hose, noticed no smoke, and shut it down.Began reading that the OMS pump can click. Checked the oil bulb and it is very hard. I didn't find any apparent leaks, though the clamp on the oil inlet to the pump was loose. I don't think it was leaking as the hose was very difficult to get off.
I mixed some fresh 50:1 premix to run it on In my home made test tank, new oem fuel hose + bulb, and new inline fuel filter. I pulled the oil feed line on the OMS and got an obvious oil/fuel mix. I attached a 1' piece of 1/4 clear tube marked every 1" with a small fullen in the open end and zip tied it so the funnel was above the oil inlet on the pump., filed with oil, and idled the engine on the premix to get air out of the line. While ut did get the air bubble out, it pushed enough fuel into the line that it flowed back into the funnel and the oil seems to be mixed with fuel. In 4-5 min of idling, it Lever seemed to pull anything out of the line.
On the premix, the engine idles in my test tank as I would expect. Using a IR thermometer, head temps are 142-150. I pulled the plugs and there is no metal and they look pretty normal. They only have maybe 6-8 hours of runtime.
I'll check compression as soon as I can locate my tester.
The clicking is hard to localize, but seems loudest at the bottom of the OMS pump at what I think in the pulse line, but i cant really tell if its higher toward the flywheel. Definetely in that area. Pumping the fuel bulb didn't change the clicking.
1- I'm guessing this means the fuel diaphram in the OMS has ruptured. im reading this pump likely doesnt have a rebuild kit available and replacement is needed. I'll wait for the compression test before replacing the pump to see if there are any other apparent issues. I prefer using VRO over pre-mix.
2- Is this clicking/ticking typical of the OMS pump or should I look at the flywheel area?
3- would the valve in the oil primer bulb prevent fuel from backing into the oil tank or should I just go ahead and pull it, clean it out, and put in a new filter?
Video of it idling-
Noticed my engine seemed to be clicking loudly at idle on the water and I think shook a bit more at low rpm than normal and maybe a bit sluggish. I never got an alarm.
Brought in home and started it on the hose, noticed no smoke, and shut it down.Began reading that the OMS pump can click. Checked the oil bulb and it is very hard. I didn't find any apparent leaks, though the clamp on the oil inlet to the pump was loose. I don't think it was leaking as the hose was very difficult to get off.
I mixed some fresh 50:1 premix to run it on In my home made test tank, new oem fuel hose + bulb, and new inline fuel filter. I pulled the oil feed line on the OMS and got an obvious oil/fuel mix. I attached a 1' piece of 1/4 clear tube marked every 1" with a small fullen in the open end and zip tied it so the funnel was above the oil inlet on the pump., filed with oil, and idled the engine on the premix to get air out of the line. While ut did get the air bubble out, it pushed enough fuel into the line that it flowed back into the funnel and the oil seems to be mixed with fuel. In 4-5 min of idling, it Lever seemed to pull anything out of the line.
On the premix, the engine idles in my test tank as I would expect. Using a IR thermometer, head temps are 142-150. I pulled the plugs and there is no metal and they look pretty normal. They only have maybe 6-8 hours of runtime.
I'll check compression as soon as I can locate my tester.
The clicking is hard to localize, but seems loudest at the bottom of the OMS pump at what I think in the pulse line, but i cant really tell if its higher toward the flywheel. Definetely in that area. Pumping the fuel bulb didn't change the clicking.
1- I'm guessing this means the fuel diaphram in the OMS has ruptured. im reading this pump likely doesnt have a rebuild kit available and replacement is needed. I'll wait for the compression test before replacing the pump to see if there are any other apparent issues. I prefer using VRO over pre-mix.
2- Is this clicking/ticking typical of the OMS pump or should I look at the flywheel area?
3- would the valve in the oil primer bulb prevent fuel from backing into the oil tank or should I just go ahead and pull it, clean it out, and put in a new filter?
Video of it idling-
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