Fouled Crankcase.-

[Sea Rider]

This is a 2 stroke Tohatsu 18 HP motor with around 150 worked hours, exhaust covers and chambers, cylinder head as in (2), pistons were impeccable decarboned and cleaned to mint condition as in (2) on last full restoration. Due to achieving poor acceleration when opening up the throttle fast decided to remove the cylinder head assuming was having water intrusion in the combustion chambers, but when removed found this awful scenario. Data : The owner uses a cheap 2 stroke uncertified TCW-3 oil mixed at 50 : 1 and run at low to medium speeds on daily basis powering a medium size boat used as as a work boat and tender. Know that on 2 strokes 2 cylinder motors cylinders does not carbon up same, usually it's one or the other, but this one is the worse seen. Assume it's a combo of poor oil quality + long slow revving ?

New NGK spark plugs were well gaped to specs, all gaskets were installed brand new and torqued to specs and the time advance/carb perfectly synched. Ideas, tech wild guessings that accounts for such scenario ?

Happy Boating

 

[Faztbullet]

No such thing as a uncertified TC-W3 oil. If bottle has printed TC-W3 on it, it had a certification.

 

[Sea Rider]

No such thing as a uncertified TC-W3 oil. If bottle has printed TC-W3 on it, it had a certification.

This local bottled crap TC-W3 Oil is not mentioned in the 2 stroke cycle Registered Marine Oils and that says much about its cheap quality. Now a days can write whatever you like on the bottle...

Happy Boating​

 

[dingbat]

This local bottled crap TC-W3 Oil is not mentioned in the 2 stroke cycle Registered Marine Oils and that says much about its cheap quality. Now a days can write whatever you like on the bottle...

Happy Boating​

What certification number are they using?
Have not seen a bottle/jug of oil w/o a certification number stamped somewhere on the container.

 

[robert graham]

A work boat/motor must get the worst possible treatment…Low RPM’s, no real TLC/preventive maintenance, never reaching optimum operating temperature, on/off, etc. etc….It would probably help to run the motor wide open/max RPM’s once a day or so. I like the Lucas 100% synthetic outboard motor oil in my old C90 Yamaha premix….and since I rarely run 5500 RPM’s, I use slightly less oil than the 50:1 mix….A product like Yamaha Ringfree might help reduce carbon….

 

[Faztbullet]

Post a picture of said bottle......

 

[Chris1956]

Gee, several of those Lucas synthetic 2 cycle oil products are not TCW-III rated. They advertise that "It is formulated to meet or exceed ISO EGD, JASO FD and API TC.". Anyone know those certifications?

 

[racerone]

Ask 10 boat owners about oil and you get 20 different ideas and opinions.----It will not change.

 

[Lou C]

Gee, several of those Lucas synthetic 2 cycle oil products are not TCW-III rated. They advertise that "It is formulated to meet or exceed ISO EGD, JASO FD and API TC.". Anyone know those certifications?

those I believe are certs for air cooled 2 strokes like weed wackers and blowers. technically they could be used in an outboard but due to the low ash forumlation (vs no ash in TCW-III) you might get more deposits. Air cooled 2 strokes run much hotter because of air cooling and also a weedwacker/blower etc runs at 9000 rpm vs outboards that run slower and cooler. So typically ash is added as an anti wear agent in TC (air cooled) 2 stroke oils but for TCW-III (water cooled) they use a no ash formulation.
However you should NOT use TCW-III in an air cooled 2 stroke, the only exception I know of (because I own one) are Toro 2 stroke snowblowers and Lawn Boy 2 stroke lawnmowers, these were spec'd to get TCW-III oil, presumably to reduce deposits due to running slower and cooler than other air cooled 2 strokes.

 

[Sea Rider]

This guy is the culprit : ​

Have checked it up in the TC-W3 Registered Two-stroke-cycle Marine Oils and there's nothing about that oil branded as Vistony or Aquaoil although bottle states low ash NNMA TC-W3 rated. Have used moon back Tohatsu, Chevron. Akron, Yamalube and now Amalie Pro, all being excellent Certified TC-W3 oils with way less carbon build up formations seen at high hours use.

Happy Boating​

 

[Lou C]

just like counterfeit 'fake' parts I guess we can have fake certs.
I use Mercruiser 25/40 in my inboard and Mercruiser High Performance gear lube in the outdrive, no problems/issues
In my Echo 2 strokes and my Husky chain saw I use the Echo semi syn TC 2 stroke oil
in the Toro/Suzuki 2 stroke snow blower I use Pennzoil full syn (no longer available) TCW-III, low deposits, good performance. You can use the TC 2 stroke oil in the snow blower but the TCW-III results in less deposits, these run pretty cool and are governed to 3600 rpm.

 

[Sea Rider]

A work boat/motor must get the worst possible treatment…Low RPM’s, no real TLC/preventive maintenance, never reaching optimum operating temperature, on/off, etc. etc….It would probably help to run the motor wide open/max RPM’s once a day or so. I like the Lucas 100% synthetic outboard motor oil in my old C90 Yamaha premix….and since I rarely run 5500 RPM’s, I use slightly less oil than the 50:1 mix….A product like Yamaha Ringfree might help reduce carbon….

Yep 2 strokes motors are not ideal to be used for long heavy work operations or constant daily tender use at very low rpm, worse if lubed or even excessively lubed way over 50:1 with a crapyy 2 stroke TC-W3 oil. Decarbon products such as CRC, Yam Ringfree, Quicksilver and others are gone, seems will not be imported anymore, need be ordered by ship as are highly flamable products, unless smuggling some cans in your suitcase to your own risk. I'm a firm believer those mentioned products really works well if squirted inside carb at regular 50 clocked worked hours...

Happy Boating​

 

[dingbat]

This guy is the culprit : ​

View attachment 353404

Have checked it up in the TC-W3 Registered Two-stroke-cycle Marine Oils and there's nothing about that oil branded as Vistony or Aquaoil although bottle states low ash NNMA TC-W3 rated. Have used moon back Tohatsu, Chevron. Akron, Yamalube and now Amalie Pro, all being excellent Certified TC-W3 oils with way less carbon build up formations seen at high hours use.

Happy Boating​

RL-30111R
It’s on the list….

https://www.nmma.org/assets/cabinets/Cabinet456/2020%20TC-W3%20Registered%20Two-Stroke-Cycle%20Marine%20Oils.pdf

 

[Faztbullet]

Yep its certified... need to look elsewhere as could be several things

 

[dingbat]

Decarbon products such as CRC, Yam Ringfree, Quicksilver and others are gone, seems will not be imported anymore, need be ordered by ship as are highly flamable products, unless smuggling some cans in your suitcase to your own risk. I'm a firm believer those mentioned products really works well if squirted inside carb at regular 50 clocked worked hours...

Happy Boating​

I have not “decarbed” in years.

Easier to prevent carbon build up running an oil with an carbon additive (XD50) or simply add Ring Free to the fuel at each fill up per instructions on the label.

 

[racerone]

Local store has a fully stocked isle of all these potions.-----It is there because it is promoted and folks buy the stuff.----Some work as described.

 

[Lou C]

I think the best thing you can do is run a full synthetic 2 stroke oil because they are likely to burn cleaner with less deposits. I have never had to de carb any of my 2 stroke equipement and the snow blower is 23 years old, the Echo stuff is 15+ years old, even the chain saw is 10 years old. The snowblower and Echo stuff gets regularly used every year.
Care in mixing your 2 stroke mix also helps, more oil is not always a good thing.

 

[Sea Rider]

It was not listed in the 2013 chart, now is in the 2020, is the list upgraded yearly ? Vistony must be buying large quantities from a general US suplier, I don't think they've invested money in breaking down an engine to achieve their brand certification. Assume that any standard 2 stroke TC-W3 from that list used to lube a work boat's motor run at low to middle range non plane rpm for long hour use will carbon up any motor run that way ?

Not my case as always run my horses 4.5-6.0 K rpm depending if in a hurry or not. Down here CRC decarbonizer or any other decarbon product is not known or promoted, to my luck ended buying some left overs cans from the Merc's dealer.

Always run 50:1 not a drop more, applying CRC squirts thru the carb at each 50 metered run hours keeps the motor idling as a swiss clock, achieving faster aceleration from a dead stop along reeving strong throughtout the whole throttle range.

Full synthetic 2 stoke oil is very expensive, as I boat all year round my oil-only budget would skyrocket. My motors are very happy being lubed with Amalie Pro TC-W3 oil for the last 10 years know.

Happy Boating​

 

[Faztbullet]

Oil companies cannot certify their own oil, has to be certified thru NMMA testing. Motor has other problems than oil type due to look of piston

 

[Sea Rider]

Both pistons and cylinder head were cleaned to near mint condition, the cylinder head gasket was found shot, overheated at one extreme, surely accounts for such uneven carbon up ? Will need to install a new one in...​

On these motors there will always be one piston carboning up way more than the other, it's the nature of the beast...

Happy Boating