Running the outboard hard without oil....now what?

[tdhotti]

Originally Posted by rslifkin

If you're lucky it's got a low oil cutoff and just needs a refill.

That was my first guess

[Cheechako]

It's 4 stroke. Tell the mechanic that it was full oil when you started and read low when it stopped. It shouldnt burn oil that fast. Something caused that, not your lack of refilling it in 2 hours use.

[CarinaPDX]

Not telling your mechanic that the oil was off the dip stick is making him chase down irrelevant paths, for which he should charge you generously. Really, own up to it. If you can tell all of us at the risk of looking stupid, then you can tell your mechanic.

I am not a mechanic, or anything close to it, so take it with a grain of salt. There are ways to suck the oil out of the crank IIRC, including a stuck PVC valve. But I would think you would notice the blue exhaust, and it is even possible the engine is fouled with oil and carbon. But maybe not. Your mechanic is the one to solve this, not us kibitzers...

Good luck,

Greg

[wallda]

Also, keep in mind there is a difference between running and repaired. If you husband gets it running, with out addressing the oil consumption issue and verification that any damaged parts are repaired (up to replacing/rebuilding the power head) you still have a time bomb.

Now is the time to be completely honest with your mechanic.

[C420sailor]

Rebuild that puppy. I wouldn’t trust an engine that went through something like that.

[NorthCoastJoe]

Here is my take on it.

Add oil and try to restart it, maybe a low oil kill on it. I do not know that motor so just general motor testing here.

Then the normal testing list is. Compression, ignition, fuel, for a fail-to-run condition.

Most likely the compression is good, you would have noticed a loss of power before it quit.

Is it getting fuel? A shot of starting fluid to the carbs if it pops and dies it's a fuel problem, and ignition is good. If nothing happens I would look at ignition.
If it has a low oil cutout it will kill the ignition.

The low oil might be a secondary issue and if it only takes a little to get back up on the dipstick it may be fine.

I will be in Loch Lomond tomorrow morning ( Monday ) dock "B" the only sailboat with a boom tent. I can check it out for you. Ex motor builder.

[Compass790]

Originally Posted by NorthCoastJoe

Here is my take on it.

Add oil and try to restart it, maybe a low oil kill on it. I do not know that motor so just general motor testing here.

Then the normal testing list is. Compression, ignition, fuel, for a fail-to-run condition.

Most likely the compression is good, you would have noticed a loss of power before it quit.

Is it getting fuel? A shot of starting fluid to the carbs if it pops and dies it's a fuel problem, and ignition is good. If nothing happens I would look at ignition.
If it has a low oil cutout it will kill the ignition.

The low oil might be a secondary issue and if it only takes a little to get back up on the dipstick it may be fine.

I will be in Loch Lomond tomorrow morning ( Monday ) dock "B" the only sailboat with a boom tent. I can check it out for you. Ex motor builder.

You might want to check post #13, Scubaseas clearly knows those engines.
Not looking for argument, just trying to help with possible causes.

[gamayun]

Hey guys, thanks again for all the suggestions. I love the help and I learned a lot, but before you get all judgemental on me, just know that he ain't my hubby -- he belongs to my friend -- so I'm not telling him what to do. When he showed me the texts from his mechanic, that's when I asked him whether he told the guy the oil was run low. I posted here because I was trying to offer up some ideas and learn about outboards. I spent a lovely few hours reading through the Yamaha shop manual, which was on the boat so that was cool (for me) because my boat has a diesel engine. The hubby is not mechanically inclined (his words) and didn't have any tools onboard so it became pretty clear, pretty quickly there wasn't much we were going to do ourselves. I'll try to report back on how it gets fixed, but at this point, it's not my boat and not my problem.....

[gamayun]

Originally Posted by Compass790

You might want to check post #13, Scubaseas clearly knows those engines.
Not looking for argument, just trying to help with possible causes.

It sounds like his staff and my friend's husband are kindred spirits too

[gamayun]

Originally Posted by NorthCoastJoe

I will be in Loch Lomond tomorrow morning ( Monday ) dock "B" the only sailboat with a boom tent. I can check it out for you. Ex motor builder.

Oh too bad! The boat got trailered to Half Moon Bay today. I would have loved to peek over your shoulder. Thank you very much for the kind offer!

[P3sailor]

Oil injection infers it would be a 2-stroke

[Tillikum]

Originally Posted by gamayun

Soooo....go easy on us. My best bud and I and her husband are shooting across San Pablo Bay to meet up with friends in Petaluma. They have a single Yamaha 50 HP. After 2 hours at around 5000 RPM it starts sputtering a bit then dies. He checks the oil and nothing is registering on the dip stick. We got a tow to Loch Lomand. The outboard turns over but is not firing up. I went through the manual and a bit of Googling. Could it be the spark plugs? Did we blow a head gasket? Hubby's not telling his mechanic that he ran the motor with no oil so the mechanic has been texting him about checking the fuel and such. Alrighty then CF friends. Lay it on us. How bad could it be? Can we check anything with limited tools and know-how?

How much does the mechanic charge per hour for goose-chasing? Tell him to stop when you figure your fine for negligence is high enough.

Checked the fuel levels?

Checked the fuel filter(s)?

On passenger vehicles, at least in metric parts of the world, it's usually one litre of oil between the top and bottom marks on the dipstick. You'll need to find out what volume of oil that is on this motor. And establish (if possible) exactly what the initial oil level was.

The mechanic can pull the spark plugs and examine the cylinder bores with a bore-scope. If the cylinder walls are are scored to *(#&#@^ as for example often happens when cold two cycle engines are over-revved on startup, then you probably have a large piece of scrap metal on your hands.

The other obvious check is to drain the oil from the sump/crankcase and see if it looks like silver paint that needs stirring.

If yes to either, then give it a careful external clean and polish and leave somewhere outboard motors tend to get stolen from!

[Shaneesprit]

He is basically tells lies to the mechanic
and do you really believe the oil level was checked?
It’s 20 years old and now abused, so now it’s toast, expensive mistake, sell it as a non runner and buy another

[CarinaPDX]

With what has been provided I don't think we know that the owner did anything wrong, other than withhold useful information from his mechanic. He might have let the crankcase oil go low (assuming it is a 4-stroke) but there are other ways for that to happen. If it is a 2-stroke then the oil injection supply running low shouldn't do more than stop the engine or alarm, but not run un-lubricated (that would be an awful design).. I think we need to await the mechanic's verdict.

Greg

[gamayun]

Yeah, I asked about the motor tonight and it sounds like the box where it was mounted on the stern needs to be repaired because the mounts were pinching through. It sounds like the motor failure was timely -- a good time to appreciate silver linings, right?