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Oil injection OR prefix... 1995 115

R

Roland J

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Oops, premix not prefix, no title ediiting.

My concern is most things eventually fail and (my new to me) 17' center console is 25 years old. I understand that the drive gear for the pump is plastic. The Motor is strong with 130 psi at all 4 cylinders and I'd like to keep it that way.

So my question is, should I trust the oil injection system or remove it and premix my fuel? (My fuel tank is 30 gallons)
 
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I had a 2002 90 2 stroke. At 10 years I converted....just pulled the gear out of the pump. Put a warning adjacent to the gas fill port to add oil so I wouldn't forget. I slept batter at night. No longer have the boat but it is fine.

Thought I was through boating. I wasn't. Last year I bought a 2002 115 2 stroke. The oil injection is still intact and have no reason to change. Still sleeping ok.

On plastic, I think it is Phenolic resin-cotton mesh. Same material used in the Ford I6 gasoline engine running the cam shaft...I once had in my hand! Proven in industrial machines. Work function is low, seems to get lubricated as the gear I pulled out had oil on it.
 
Very rare for the bottom driven oil gear to fail..that why there is no sensors for it. Most that do fail are from other problems that cause gear to fail such as overheat..
 
faztbullet said:
Very rare for the bottom driven oil gear to fail..that why there is no sensors for it. Most that do fail are from other problems that cause gear to fail such as overheat..
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Are there other things that would cause oil injection failure besides gear failure? Any preventive maintenance that should be done?
If it fails does it toast the engine right away or are there signs of failure to know about?
 
Bubbles in the oil line but line is clear and you should be able to see any. If you don't disturb oil lines and keep oil in the tank no reason for bubbles.
 
Are there other things that would cause oil injection failure besides gear failure?​
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Oil cap cracked allowing water into oil tank, oil feed line from tank breakage...oil failures are not common on these. More common problems are pistons due toluuging and over reving as skirts break on pistons
 
Mine broke the plastic line and damaged the motor running in the dark. It was first trip out in the spring in NW Ontario. Inspect and replace oil lines, for sure. Otherwise no troubles with this 1989 115. Gotta rebuild it but it still runs pretty strong, only 90 psi on all 4.. Amsoil Injector oil musta saved it.
 
Cool so inspecting the oil lines and replacing if needed.

faztbullet said:
More common problems are pistons due toluuging and over reving as skirts break on pistons
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What exactly is lugging a engine or more specifically a boat motor? I think I understand how lugging applies to a stick shift car but I'm not sure how this happens on a boat. Thanks again everyone for all the input.
 
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Roland J said:
Cool so inspecting the oil lines and replacing if needed.




What exactly is lugging a engine or more specifically a boat motor? I think I understand how lugging applies to a stick shift car but I'm not sure how this happens on a boat. Thanks again everyone for all the input.
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Test for lugging: Load you boat normally. Get out on smooth water and firewall throttle, trimming for best speed. Check the tach. Is it within, and preferably at-near the top of the recommended operating range. I think I recall my 115 range at 4500-5500. On it, preferably tuned, for 5000 to the top is where you should be. If you tach is reading like 4000, you are lugging!
 
Roland J said:
Oops, premix not prefix, no title ediiting.

My concern is most things eventually fail and (my new to me) 17' center console is 25 years old. I understand that the drive gear for the pump is plastic. The Motor is strong with 130 psi at all 4 cylinders and I'd like to keep it that way.

So my question is, should I trust the oil injection system or remove it and premix my fuel? (My fuel tank is 30 gallons)
Click to expand...

I would be hesitant to remove the oil injection system, I was pretty quick to blame the VRO system when fuel and sealed into my oil tank. In general they are fairly reliable systems and rarely fail. Best thing is to keep tabs of your oil level and ensure it’s falling as you use the engine. The U bend pipe going from the oil pump out put to the y intersection needs to be clear so you can see that there are no bubbles forming in there.

I’ve recently replaced my check valve and had issues pumping oil so I premixed 100:1 as a precaution but seems to be working now. If it helps you sleep at night though just remove the pump drive shaft and sensors, additionally cap of the pipes from the output.
 
Texasmark said:
Test for lugging: Load you boat normally. Get out on smooth water and firewall throttle, trimming for best speed. Check the tach. Is it within, and preferably at-near the top of the recommended operating range. I think I recall my 115 range at 4500-5500. On it, preferably tuned, for 5000 to the top is where you should be. If you tach is reading like 4000, you are lugging!
Click to expand...

Got it. Basically too much load on the powerhead. Maybe from something like a prop with too much pitch, or too small of a engine on the boat...

Good stuff.
 
Harryyabs said:
I would be hesitant to remove the oil injection system, I was pretty quick to blame the VRO system when fuel and sealed into my oil tank. In general they are fairly reliable systems and rarely fail. Best thing is to keep tabs of your oil level and ensure it’s falling as you use the engine. The U bend pipe going from the oil pump out put to the y intersection needs to be clear so you can see that there are no bubbles forming in there.

I’ve recently replaced my check valve.
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The downstream clear tube comment is interesting. What type of clear tubing do you use that is good in that application?

You mention a check valve. I was not aware that a check valve is in the system. This is good to know and may explain something I found in my up stream remote fuel filter.

When I replaced my remote fuel filter (3 feet before the motor) I found the fuel in the filter was blue green! Looking like premixed fuel. Then I pumped the fuel tank prime bulb with the filter off and my fuel was orange/yellow. I dismissed that until now that you mention a check valve.

So I'm wondering if that was actually premixed fuel working it's way back up the fuel line??? In the back of my mind I was thinking the sat somehow the fuel filter changed the color of the fuel but now that I say that out loud that just sound silly. So now I'm wondering how the 2 stroke oil went the wrong way?
 
The U bend pipe should be clear by default I believe but mine was just not transparent enough at all so could not make out oil flow through it. It’s a very short piece of piping but will give you an indication of oil getting into Y meet section.

The clear tube runs into the 1 way / check valve I was talking about. As for the fuel filter premix issue I wouldn’t really know where to start with that, best to ask someone else but if you want to check the valve is working disconnect pipes either side and blow into it. You should only be able to blow down and not back up.
 
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