Opps, did I run my 2-cycle with no oil!!!!!!!

[chrisg]

I have a 99 2-cycle 60HP Merc BF. It has the oil tank on the motor. I had filled it up once and so far went through 24 gallons of fuel.

I tool it out yesterday, and it just died while going full out. Figured I ran out of fuel, so I changed tanks and started it back up. It ran for a few minutes and died again!. Water was coming out the hole, so it was no a cooling issue. So, I started it up again (had to re-prime the bulb) and slowly went home.

I then opened and re-filled the oil tank, ya it took a bit to fill. But I figured it had a beeper that sounds when the oil is low. I had checked the wiring earlier and tested by sorting out the oil sensor (Someone here told me what to do) and it did beep. Once I re-filled the oil tank, I took the boat out again, and it ran fine.

Does anyone know, does these Mercs have a sensor that will cut the motor out if it detects the oil is low? I will now keep a bottle of 2-cycle oil in the boat at all times. I guess I should just top up the oil tank when I fill the gas tank (which is 12 Gal.)

Hope I did not hurt anything. Any ideas?

 

[chrisg]

Re: Opps, did I run my 2-cycle with no oil!!!!!!!

Update: The motor started up today and ran with no issues. This is after I re-filled the oil tank. Has anyone heard of this situation where the engine will turn off if its low on oil? Perhaps a safety feature? I would have expected an alarm to go off to indicate the oil was low. ( there is no way you can see the oil level in the holding tank.)

 

[chrisg]

Re: Opps, did I run my 2-cycle with no oil!!!!!!!

Further update: I noticed now the motor has a 'rattling' sound at idle, and it bogs down when I run full out. After its been running for a while ( 10-15 minutes) it runs OK at WOT. Except the tach has stopped working.

I would assume the low oil alarm would have come on if the tank went low. ( When I shorted the two wires coming from the bottom of the oil tank together, it beeped.)

How can I tell if the motor is now messed up? and how can I tell if the motor is getting oil? ( that the mixer has not stopped working)

 

[Knightgang]

Re: Opps, did I run my 2-cycle with no oil!!!!!!!

Grab your manual, there should be a procedure outlined in there that will guage oil usage in small quanities to ensure it is working properly...

 

[matt9923]

Re: Opps, did I run my 2-cycle with no oil!!!!!!!

maybe you fried your motor.... pull the head and look.

 

[pops]

Re: Opps, did I run my 2-cycle with no oil!!!!!!!

If the oil tank sensor is working properly (you said it beeped during test), it will alert you to low oil in the tank, but there is no engine shut off.

If the oil pump or any other part of the oil system quits pumping oil to the engine, there are no sensors, shut offs, etc. to tell you the engine is not getting oil. You can fry an engine with a full oil tank! One failure mode is a sheared tang on the plastic oil pump drive shaft.

The oil tank sensor went bad on my motor (1995 115 HP) and beeped constantly. That's when I figured out that there is no real engine protection on these auto oil systems. I keep extra oil in my boat, but doubt that I would dedect a "no oil" situation in time to save the engine.

 

[Knightgang]

Re: Opps, did I run my 2-cycle with no oil!!!!!!!

Your engine is probably fine. You are just paranoid at this point. I have en engine shutting off before and thought is was an oil self safety issue. Found out there is no such thing... Mine went away, not real sure what it was, but I eventually had to replace sparkplug wire caps. Was it realated, I do not know...

 

[chrisg]

Re: Opps, did I run my 2-cycle with no oil!!!!!!!

Your engine is probably fine. You are just paranoid at this point. I have en engine shutting off before and thought is was an oil self safety issue. Found out there is no such thing... Mine went away, not real sure what it was, but I eventually had to replace sparkplug wire caps. Was it realated, I do not know...

paranoid is correct, I had replace an old 115 merc that came with the toon, was told the engine was bad. ya, after a while it did run OK, just dont know why the tach stopped. perhaps its just the plugs.

Well I pulled it out of the water and its at the marina to get it winterized. I asked them to check the motor out first.

Thanks

CG

 

[chrisg]

Re: Opps, did I run my 2-cycle with no oil!!!!!!!

I may have figured out the engine cut out problem. (If all else fails, read the manual). Apparently there is this over RPM limiter which shuts down the motor if the RPMs get above 5700. Well, with just me, ( and when the tach was working) it read around 5700 full out (18.7MPH). So now that the boats has been in the water for all season, it has stuff hanging on the lower unit, causing cavitation, which probably caused the RPMs to go above 5700, causing the motor to shut down. That must be it, because it worked fine going slow, just not WOT. I should have cleaned the motor then tried it. ( Its out of the water now)

 

[hibbert6]

Re: Opps, did I run my 2-cycle with no oil!!!!!!!

If the fail-safe cutoff is at 5700 RPM, I would assume the redline is a bit below that, maybe 5500?

In which case, you might want to consider a different prop. You want to be pretty near redline at WOT, but certainly not anywhere near the emergency cutoff RPM.

Post this question on the PROP board and they'll tell you how to determine the right prop. It will also get you higher top speed.

Dave

 

[cvsalmon1]

Re: Opps, did I run my 2-cycle with no oil!!!!!!!

That motor should have an alarm if it gets low on oil before running out,also has a sensor that causes an alarm when the oil pump isn't moving oil. The RPM limiter should not kill the motor, it will cause a misfire that prevents the motor from overreving. You probably overheated the motor by running it out of oil. After it cooled down the seized parts loosened up again so it would turn over again.On the other hand 24 gals of gas should have burned less than 2 qts of oil. Not sure how much your oil tank holds. Maybe you need to do a little more research.
Chris