What is the harm of running to rich of an oil mixture?

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Very rich oil mixes 20:1 often result in lower carbon build up on the piston. There are several documented experiments on this topic. If there is enough oil to keep surfaces wetted and quenched with oil the oil tends to clean rather than deposit and bake on. Just like a well oil frying pan resists things sticking to it.

On a well adjusted saw the worst carbon buildup I have seen is running at 50:1 with factory reccomended mix. Ironically 32:1 left the piston crown significantly cleaner.

I would take it as fact if TW states it. Its 99.9% correct.
I now run 40:1.

I bet most of the carbon build up comes from the petrol not the oil.
 
Why would a Premium MARINE grade oil be bad?

Seems that the potential issues are for more gunked up deposits in the crankcase, more carbon buildup in the combustion chamber, more plug fouling, as well as muffler screens clogging up faster. Also there will be more smoke, which leads to the last three items in my list. I have found that running old dyno premix oil will lead to all four items, even running at 50:1.

Use 100% synthetic at least JASO FC rated (or equivalent if not rated, like Stihl Ultra) and your saw will run far better and last longer, with fewer issues and a lot less smoke. FD is even better. FB will smoke and clog muffler screens and cause more gunk and carbon buildup in your engine. Marine TWC rated oil will cause even more problems in your saws.

WHY is Marine 2 stroke oil n/g for a chainsaw?
What would it do to a saw??

Please...I'm just asking.

Thanks,

CTwoodnut in the Western CT Hillz :rock:
 
This should be about Marine 2 Stroke Oil...

Hi All I just replied to a thread about 'oils', but I don't think something worked right there...

I've been reading about 2 Stroke Oils, and was wondering WHY a good/premium Marine TWC rated oil wouldn't be good for a saw engine.

Why & what would it do to the engine? :msp_confused:

I'm also a boater and have lots of Premium Mercury 2 stroke oil.

Don't shoot me......cuz I'm jus askin'...

Thanks!

CTwoodnutt in the Western CT hillz :rock:
 
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Hi All

I've been reading about 2 Stroke Oils, and was wondering WHY a good/premium Marine TWC rated oil wouldn't be good for a saw engine.

Why & what would it do to the engine? :msp_confused:

I'm also a boater and have lots of Premium Mercury 2 stroke oil.

:

I'm sure there are all kinds of scientific reasons why marine oil would be really bad for your saw but in "real life" I can verify that I have had no issues with it running 32:1 in a variety of saws. I don't use it all the time and use all types of two stroke oils and have never had a lubrication related problem. Including carbon or plug issues. (I have had one spark plug go bad in my career. (chain saw plugs only being referred to here)
 
For CTwoodnut,

The oil for your merc is rated with the outdated API TCW system. TC stands for two cyle, W for water cooled. That rating has been upgraded over the years from 1 to II to III as the oils got better. TCW III is rated for combustion at a max of 7500 or 8000 rpm in a water cooled engine. Any faster than that and the combustion reaction is happening to fast for the oil to ingnite, much less burn off completely. The current ISOLEGD and JASO FB, FC, FD standards are deigned for all two stroke engines. The best TCW III rated oil isn't even as good as JASO FB, and that was current in the late eighties early nineties. Most saws free rev to over 12,500 rpms, mod saws to 14,500 +. At that speed the oil to use is the best you can get unless you like having your saw in the repair shop. Your little chainsaw engine is much less expensive than your outboard for sure, but its undergoing a hell of a lot more stress when its running. Keep it happy with good oil. For all the 16 and 25 to 1 guys out there, echo has a test facility in Illinois where they run engines continuously with varied mix ratios, under controlled conditions they can run an engine at 300:1 for 100 hours with no damage, keep in mind controlled conditions means they have really good gas, probably without ethanol.
 
For CTwoodnut,

The oil for your merc is rated with the outdated API TCW system. TC stands for two cyle, W for water cooled. That rating has been upgraded over the years from 1 to II to III as the oils got better. TCW III is rated for combustion at a max of 7500 or 8000 rpm in a water cooled engine. Any faster than that and the combustion reaction is happening to fast for the oil to ingnite, much less burn off completely. The current ISOLEGD and JASO FB, FC, FD standards are deigned for all two stroke engines. The best TCW III rated oil isn't even as good as JASO FB, and that was current in the late eighties early nineties. Most saws free rev to over 12,500 rpms, mod saws to 14,500 +. At that speed the oil to use is the best you can get unless you like having your saw in the repair shop. Your little chainsaw engine is much less expensive than your outboard for sure, but its undergoing a hell of a lot more stress when its running. Keep it happy with good oil. For all the 16 and 25 to 1 guys out there, echo has a test facility in Illinois where they run engines continuously with varied mix ratios, under controlled conditions they can run an engine at 300:1 for 100 hours with no damage, keep in mind controlled conditions means they have really good gas, probably without ethanol.

Okay, what about going the other way? Why is TCW oil better for water cooled two strokes?

I ask because I have been running TCW in my Seaking outboard, which is what is called for in the manual, but this motor is "technically" air cooled, though it is exhaust water cooled (i think).

But I've read on another forum that it should be using air-cooled mix, so not quite sure now...
 
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Great info here! THANKX!!!

For CTwoodnut,

The oil for your merc is rated with the outdated API TCW system. TC stands for two cyle, W for water cooled. That rating has been upgraded over the years from 1 to II to III as the oils got better. TCW III is rated for combustion at a max of 7500 or 8000 rpm in a water cooled engine. Any faster than that and the combustion reaction is happening to fast for the oil to ingnite, much less burn off completely. The current ISOLEGD and JASO FB, FC, FD standards are deigned for all two stroke engines. The best TCW III rated oil isn't even as good as JASO FB, and that was current in the late eighties early nineties. Most saws free rev to over 12,500 rpms, mod saws to 14,500 +. At that speed the oil to use is the best you can get unless you like having your saw in the repair shop. Your little chainsaw engine is much less expensive than your outboard for sure, but its undergoing a hell of a lot more stress when its running. Keep it happy with good oil. For all the 16 and 25 to 1 guys out there, echo has a test facility in Illinois where they run engines continuously with varied mix ratios, under controlled conditions they can run an engine at 300:1 for 100 hours with no damage, keep in mind controlled conditions means they have really good gas, probably without ethanol.


:msp_w00t:
This is some great information here!
And I Thank You!

....."and now for something completely different"...(as Monty Python used to say)...

Has anybody heard of/used a product called 'LIQUI-MOLY' made by a German company?
[LIQUI MOLY GMBH, ULM, GERMANY].

It comes in a can, and is about $9.00 for a 300ml can.
I buy it at 'Advance Auto'.

This stuff is technically and/or chemically MoS2, or 'Molybdenum Disulphide'.
It was originally developed for the Aero Space industry, and used in Jet/Turbine engines....(HEY-these are also Air-Cooled, aren't they? (Hence, the chainsaw engine question)...

It would be added to the oil, in your car/truck, and 'molecularly' bonds to metal, and drastically reduces friction.

BTW - (This stuff 'AIN'T' Slick 50...it's way more 'sophisticated')!
- (It is especially useful WHEN REBUILDING ENGINES/coating the parts, while assembling).

I used something similiar to this "100 years ago" (in 1980) while assembling a rebuilt 2600cc Capri motor). [GOD- does this show my AGE] :msp_scared:

- Sooooooooo, my question would be...couldn't we use this in a chainsaw?
I'm thinking one could just add, say a teasponful to the gas/oil every other tank or so.
Now-I don't know IF this stuff would 'burn', like the oil that we add to the gas, so I'm just "throwining this out" to the more experienced members of A.S.

Here are 2 links to this companies website: [email protected] (also)
www.liqui-moly.de
Thankx!

Irv in the Western CT Hillz :rock:
 
Sachs Dolmar at 25 to 1

Referring to a Sachs Dolmar 112 and 117 (late 1980s) specifically, do they require 25 to 1 due to bottom end lubrication or is Stihl oil at 50 to 1 OK. My Dolmar dealer sold me some Opti-2, He said it is all he uses but I prefer Stihl oil because I can get it anywhere.
 
Whether it is synthetic or not? What are the effects?

Possibly some excessive build up(carbon, calcium, lead, whatever) from incomplete combustion.

Might be a tad more smoke, stink and $ involved.

These "effects" are largely caused by the actual gas and operating conditions more than the oil these days compared to 16:1 with 40wt.

I am currently running Lucas Semi at 32;1, no issues so far. Cheap oil compared to most, I try to keep a gallon of premium mix under $5.00 since I am burning it.
 
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