Thickish Black Oil Running/dripping. Problem?

[wonniefisho]

Hi all,

With my project boat, I just noticed some thickish black oil looks like its run down from in behind the prop. I'm yet to change the gearbox oil since I've bought it (since I haven't taken it out yet) but I would have been surprised if gearbox oil was that black - could it just be unburnt oil since the last few times its been run it was at idle being flushed in the driveway? I know my 89 Johnson used to do it after flushing (but not after it had been out), but didn't think it was a common thing.

Hoping its just that.

Edited January 13, 2009 by wonniefisho

[chrisg]

Hi all,

With my project boat, I just noticed some thickish black oil looks like its run down from in behind the prop. I'm yet to change the gearbox oil since I've bought it (since I haven't taken it out yet) but I would have been surprised if gearbox oil was that black - could it just be unburnt oil since the last few times its been run it was at idle being flushed in the driveway? I know my 89 Johnson used to do it after flushing (but not after it had been out), but didn't think it was a common thing.

Hoping its just that.

Yep just unburnt gunk working its way out. Just to be sure drain a spoonful of oil from the gearbox and check the colour.

My money would be on the gunk though.

Cheers

Chris

[wonniefisho]

Yep just unburnt gunk working its way out. Just to be sure drain a spoonful of oil from the gearbox and check the colour.

My money would be on the gunk though.

Cheers

Chris

Thanks mate.

Yeah, I'll be doing a gearbox oil change before I take it out, whenever that will happen. Still in the midst of sanding prior to filling some small dents, etc and painting, then refitting, then do the floor, then the instruments and controls, then the canopy, then I might think about getting some blood on it.

[a boat]

Hi, I doubt it will be gear oil if it is black (unless it is very old). Gear oil is a honey colour or turns milky with water. What it will be is unburtn 2-Stroke oil caused by running inferior oil, too much oil or more likely the engine is not reaching its correct operating temp at low speed and therefore running cold. I would check the thermostats and make sure the engine is reaching correct temp and use good quality oil (something like XD-50) at the right ratio of 50:1.

Cheers,

Huey.

[wonniefisho]

Hi, I doubt it will be gear oil if it is black (unless it is very old). Gear oil is a honey colour or turns milky with water. What it will be is unburtn 2-Stroke oil caused by running inferior oil, too much oil or more likely the engine is not reaching its correct operating temp at low speed and therefore running cold. I would check the thermostats and make sure the engine is reaching correct temp and use good quality oil (something like XD-50) at the right ratio of 50:1.

Cheers,

Huey.

Thanks.

I just realised why - because I was using premix with the VRO still hooked up so it was getting too much oil. I'll be changing the plugs and have some fresh synthetic 2 stroke oil to do a new premix (now I've disabled the VRO). It was only for a flush, so hopefully should be OK.

[achjimmy]

Thanks.

I just realised why - because I was using premix with the VRO still hooked up so it was getting too much oil. I'll be changing the plugs and have some fresh synthetic 2 stroke oil to do a new premix (now I've disabled the VRO). It was only for a flush, so hopefully should be OK.

I hope i am not starting something but why did you disconect the oil injection if it was obviusly working?

[wonniefisho]

I hope i am not starting something but why did you disconect the oil injection if it was obviusly working?

Yes mate, this VRO business has been done to death before, but anyway, theres tonnes of info on disabling it with no ill effects, even if the VRO unit is working well, I'm more than happy to premix and ENSURE its getting oil - if its getting fuel its getting oil. Not to mention get rid of the 5 litre oil container in the boat. Plus the previous owner said that he had the occasional low oil alarm sound irregularly over the years which couldn't be explained by a couple of mechanics other than a 'possible' issue with the VRO unit. Given, I agree a working VRO has its advantages, having no real knowledge of the history of the motor other than what a previous seller says (and we all know how honest a lot of sellers are anyway), rather than hope for the best the VRO is ok, its just as easy to disable it, a 10min job, and use premix which I'm used to using anyway. Thats my decision and I'm happy with it.

Edited January 14, 2009 by wonniefisho

[a boat]

Hi, fit new plugs, make sure she is reaching correct temp and run XD-50 on pre-mix if you like and enjoy her. You will not have done any real drama with it and it might also pay to power tune that engine. I think from memory you have a cross flow V4 OMC and they like to be power tuned every 100 odd hours and it will chemically clean the piston rings and can help with failures due to sticking and then broken piston rings.

Cheers,

Huey.

[wonniefisho]

I've got Valvoline 2 stroke outboard Synthetic. I assume thats OK.

[a boat]

I've got Valvoline 2 stroke outboard Synthetic. I assume thats OK.

Yes that will be fine, but I think XD-50 with the additives they put in to help with carbon build-up on old tech engines and in particular cross flow V4 engines is a better oil in my opinion. Either way it would be good to power tune her and then stick with one oil no matter what brand it is.

Cheers,

Huey.