2 stroke oil recommendation

Joined
Sep 23, 2014
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Toronto Canada
I think mixing two stroke fuel at128:1 fuel to oil will kill the engine. There are times an oil injection system will go very lean on oil, but only under no load conditions. It is unlikely this Harley golf cart has a plain bearing around the wrist pin, but it might if it's very old. If it has a plain bearing I would mix at about 25:1. With a needle bearing at the wrist pin , about 40:1. I've never seen a two stroke with a plain lower bearing, but if this is the case, again I would use about 25:1.
I own an old outboard with plain bearing wrist pins and 25:1 with modern oils appears to work perfectly. I use any two stroke oil made in the last 30 years.
A ratio of 128:1 fuel/oil mix is not acceptable in any two stroke engine I am aware of.
 
Joined
Jul 15, 2003
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MN
I think mixing two stroke fuel at128:1 fuel to oil will kill the engine. There are times an oil injection system will go very lean on oil, but only under no load conditions. It is unlikely this Harley golf cart has a plain bearing around the wrist pin, but it might if it's very old. If it has a plain bearing I would mix at about 25:1. With a needle bearing at the wrist pin , about 40:1. I've never seen a two stroke with a plain lower bearing, but if this is the case, again I would use about 25:1.
I own an old outboard with plain bearing wrist pins and 25:1 with modern oils appears to work perfectly. I use any two stroke oil made in the last 30 years.
A ratio of 128:1 fuel/oil mix is not acceptable in any two stroke engine I am aware of.
It is still running since 1983, so it can't be that bad for it?
 
Joined
Sep 23, 2014
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I have never seen an engine running with this little oil so.....I looked it up. The engine produces around 12hp which is relatively low power for the 250cc displacement. Modern variable oil injection system use an oil/fuel ratio of up 150:1 under light throttle and up to 35:1 under high load.

The throttle is governed as well which would limit load at various times. This could help explain the low oil requirement, but it still seems like dangerously weak to me. There was a change made to the engine around 1969-1970. The early engine had a plain wrist pin bearing and the oil requirement was 25:1. After the change to a needle bearing around the wrist pin the ratio was changed to 85:1.

Nice service manual here...
 
Joined
Feb 15, 2003
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Jupiter, Florida
For that, just about any TCW-3 oil, or FC-FD, EG-D (latest low smoke formulation) will be just fine. Although I'm not a fan of ultra lean oil ratios.
 
Joined
Jul 15, 2003
Messages
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For that, just about any TCW-3 oil, or FC-FD, EG-D (latest low smoke formulation) will be just fine. Although I'm not a fan of ultra lean oil ratios.
Agree. I usually supplement my injection system with a little oil in the gas tank when I fill up since it gets used on campground roads for longer periods of time than at a golf course
 
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