Can I Use 4 Stroke Oil To Burn In A 2 Stroke Sea Doo ?

This has been a very interesting thread. I commend CDK for his insight. I was a bit skeptical but his antedotes are persuading.

CDK, one question. What oil would you run in an air cooled porsche?

 

http://www.sea-doo.net/techarticles/oil/oil.htm

 

Exhaust tuning is an interesting subject, but has little relation with the type of oil which is used. Technical kids experimenting with their 50 cc bikes discovered that replacing the muffler with an open pipe created an impressive F1 sound but also reduced the overall performance. Real tuning was and is impossible because it requires an organ pipe with variable length, but creating some back pressure by resonating at several rpm points has been used by the motorcycle industry. Outboards already have too much back pressure because they discharge under water and the exhaust length is determined by the shaft length.

Which additives are used in 2-stroke oil other than a senseless dye and flame retardants based on lead, aluminum or silicone?

 

But tuners of fixed length work far better than no tuner at all. Aside from loop-charging, that's the essential difference in power output between 1950s era outboards and those made 1970-2000. In alky-burner outboard racing, adjustable pipes are sometimes possible.

I only know of the one article whose link I gave on modern outboard oils.

 

I skipped that link because of its origin (manufacturer site).
A mistake: the information is excellent. I do not concur with everything, but this author knows what he is writing about!

 

Yes, I had that impression too. Informative articles on oil are few and far between.

 

This post implies that the reason 2-stroke engines have much higher emissions is the oil mixed in the fuel. This is definitely NOT the cause of the 2 stroke's higher emissions. Rather, charge dilution leading to incomplete combustion is the reason. These are due to the architectural/event timing details of the typical port-charged, loop scavenged 2 stroke engine.

This is completely distinct also from a 2-stroke diesel engine, a so-called 'uniflow' engine which is valve scavenged. 2-stroke diesels use 'sump oil' which is like any other sump oil used in any 4 stroke engine.

CDK, I'm surprised you have not mentioned the two wholly excellent seed oils for 2-stroke oil mix: Castor and jojoba. Both are outstanding lubricants, readily biodegradable and renewable. The castor is especially good as the oil's molecular structure causes it to form 'platelets' capable of lubricating even after partial degradation (combustion).



Jimbo

 

There is seems to be a lot of opinion rather than fact relating to these two stroke oils. I was involved in some testing and material specification/selection for a new engine and I can tell you that different brands and types of oil provide significantly different wear rates of the ring and liner couple. Then there is scuff resistance......

As for the results, I'm sure some here will immediately disagree with this, but in general the cheap lawnmower type oils were by far the worst and the synthetic (expensive) oils were the best.... there was an order of magnitude in difference of wear rate. It is also interesting to note that oil ranking was reasonably consistent across the different ring-liner material couples.

 

TollyWally,
Castrol GTX is very popular w motorcycles and sold everywhere. In tests it performs almost as well as synthetics. I use 50/50 20-50 and 10-30 to get a VI of 15-40.

Easy Rider

 

All the oils types have features that are better then each other but the they also have downsides so whatever you use it will be a compromise for a recreational use.
Castor oil is a perfect example, its the toughest protector there is but....what it leaves behind is such a problem it a race only oil.

 

Filled my tank with fuel and 50 to 1 olive oil. Ran her hard this weekend and I can tell no difference in performance. Plugs are still looking good and the tailpipe no longer has the pungent 2 stroke smell. I will keep running olive oil.

 

are you actualy teling me that you can mix olive oil wit gas and use with outboard ?

 

Yes, CDK had mentioned it in this thread so I did some internet research and found quite a bit of info. I will say though. I'm trying it because it was a $300 motor in the first place so it seemed like the thing to do. Really I like the smell....

 

I'll let you folks know if I have issues. (with the motor) tehe...

 

Thanks for being a Guinea pig Zappi!

Regards, Andrew.