Is PWC oil which is higher rated, better for regular 2-strokes that call for tcw-III?

jbjennings

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Just curious. I have a merc 65hp from 1973 that is in super condition (I can still see the factory cross-hatching in the cylinders) with great compression I just bought. These motors are prone to detonation and piston scuffing in my opinion. I was curious if it would be pointless to run the PWC oil or if it actually gives more scuff protection. I'm going to retard the timing as much as possible. To set the timing on this thing, you have to have a tool that I can't find anywhere, so it's difficult to get it set to 21 degrees. I'm just going to use some calipers to set the spark stop the same as my other 65 3-cylinder which never has detonation issues. I have cleaned the carbs. Hoping this thing will last at least another 40 years or until the operator expires......

Also, would using higher octane gas actually benefit this motor. My biggest fear is detonation (had it happen on my last one).
JBJ
 

bassman284

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Re: Is PWC oil which is higher rated, better for regular 2-strokes that call for tcw-

Here's a link FYI and edification: PCW vs. TCW3

I'm also going to c&p the first paragraph of the article because I enjoyed it and I'm sure other veterans of the "oil wars" will get a kick out of it as well.

There are very few subjects that stir the emotions of PWC performance enthusiasts more than to ask, what 2 stroke oil do you use and why? This site has dedicated more ‘bandwidth’ to this subject than just about any other topic. Most of the discussions end up in heated debate with no one really changing anyone else’s mind on what oil is the best anyway. We tend to vehemently defend our choice as if our very reputation depended on it. I sometimes think we are more loyal to our favorite brands of oil than to our favorite brand of ski (hopefully Sea-Doo). Well, maybe we’re not quite that loyal to our oils, but close to it. If it’s any consolation, PWC performance enthusiasts are not the only group of “motorheads” that staunchly defends their choice of oil. I belong to several other performance oriented motorsport discussion groups (Ford-Diesel and Racetech-KTM) and they do it also. With all this said, let’s all take a deep breath and put our emotions and biases in a closet somewhere and try to look at this magic miracle ‘brew’ we call 2-stroke engine oil.

Cliff notes: PWC is not actually rated higher, it's rated different, for a different application. The PWC is designed primarily for Rotax air-cooled engines. Some of those motors are kind of a hybrid liquid/air cooled. Your outboard will not do well with PWC.
 

bassman284

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Jun 24, 2006
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2,840
Re: Is PWC oil which is higher rated, better for regular 2-strokes that call for tcw-

Here's a link FYI and edification: PCW vs. TCW3

I'm also going to c&p the first paragraph of the article because I enjoyed it and I'm sure other veterans of the "oil wars" will get a kick out of it as well.

There are very few subjects that stir the emotions of PWC performance enthusiasts more than to ask, what 2 stroke oil do you use and why? This site has dedicated more ?bandwidth? to this subject than just about any other topic. Most of the discussions end up in heated debate with no one really changing anyone else?s mind on what oil is the best anyway. We tend to vehemently defend our choice as if our very reputation depended on it. I sometimes think we are more loyal to our favorite brands of oil than to our favorite brand of ski (hopefully Sea-Doo). Well, maybe we?re not quite that loyal to our oils, but close to it. If it?s any consolation, PWC performance enthusiasts are not the only group of ?motorheads? that staunchly defends their choice of oil. I belong to several other performance oriented motorsport discussion groups (Ford-Diesel and Racetech-KTM) and they do it also. With all this said, let?s all take a deep breath and put our emotions and biases in a closet somewhere and try to look at this magic miracle ?brew? we call 2-stroke engine oil.

Cliff notes: PWC is not actually rated higher, it's rated different, for a different application. The PWC is designed primarily for Rotax air-cooled engines. Some of those motors are kind of a hybrid liquid/air cooled. Your outboard will not do well with PWC.
 
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Re: Is PWC oil which is higher rated, better for regular 2-strokes that call for tcw-

I managed to make it all the way through that article, misspellings and all. What I gather from it is that PWC oil is designed for higher operating temperatures than TCW3, and if used in an engine which operates at a lower temperature (i.e. a water cooled outboard) there's a very real possibility of sticking rings and other such issues.
 

jbjennings

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Re: Is PWC oil which is higher rated, better for regular 2-strokes that call for tcw-

thanks for the replies. I'll go with full synthetic tcw-III and might consider using high octane. I tested it for the first time today and sure enough, my carb cleaning wasn't good enough or there was some varnish left in that old fuel pump. The top carb started fouliing up.
I didn't realize the PWC oil was for higher temps since my old 2-stroke pwc's are water cooled. I guess the far higher rpm's produce the heat. I should have researched it myself.
Thanks again,
JBJ
 

WIMUSKY

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Re: Is PWC oil which is higher rated, better for regular 2-strokes that call for tcw-

I guess I would use higher octane too since the octane levels were higher than today in '73. Although, after a couple short years, 1975, we went to unleaded and the octane levels dropped...... Even my 2003 4 stroke EFI calls for a minimum of 89. Around my neck of the woods that's a mid grade....
 
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Chris1956

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Mar 25, 2004
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Re: Is PWC oil which is higher rated, better for regular 2-strokes that call for tcw-

JBJ, Just curious. What is the special tool needed to set the timing? I always set my '73 850 with a timing light.
 

Chris1956

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Re: Is PWC oil which is higher rated, better for regular 2-strokes that call for tcw-

Was in Wallyworld last night. They had two synthetic PWC oils branded by Mercury (black with yellow label) and Quicksilver(grey bottle), respectively. The Mercury brand PWC oil said oil was rated API-TC and was specifically for air and water cooled 2 cycle motors like Seadoo, and not recommended for engines calling for TCW-III. The Quicksilver branded oil did not carry the TCW-III rating but did not say it was API-TC, nor did it warn about using it in Outboards requiring TCW-III.
 

jbjennings

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Re: Is PWC oil which is higher rated, better for regular 2-strokes that call for tcw-

Hey CHris,
The tool is supposed to bolt on to the side of the block and I think is basically just a pointer to show you where the mark on the flywheel should be when the #1 piston is at top dead center. I made my own pointer out of a piece of wire today and it seemed to work fine. I set it with a timing light like you and am anxious to test it out tomorrow. I feel a lot better about no detonation occurring since it's timed right now, and I also set the float needle so that it has more fuel in the bowl now. I'm thinking she should purr. Thanks for the reponse on the PWC. I'm definitely not going to use it in my merc. TCW III is cheaper anyway. I think I'm going to use the synthetic, though. I really think this is a low hours motor that has been taken good care of, and I want it to outlast me! :)
JBJ
 
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