The old Detroit two stroke has been around for a long time, and although they are no longer a production engine there's still a pile of them out there. But a lot of things have changed since the days when those engine were common, specifically diesel engine oil. The multigrade 15W/40 used today is fine for newer engines, but it's murder for an old Detroit.
Detroit engines have very specific requirements for engine oil, mainly two, 1) use only SAE40 oil, no multigrade. If you're in an extreme northern climate you might use SAE30 in the cold of winter, but it's better to use a block heater to help keep the oil warm and use SAE40, and 2) the oil must have a sulfated ash content of 1.0% or less, the more less the better. Any oil 1.0% or above does not meet the engine oil specs.
This stuff is critical for the life of these engines. Use of the wrong oil, or use of multigrade 15W/40, will result in increased oil consumption and damage to the pistons and liners causing shorter engine life.
A few oils that meet the engine specs:
Chevron Delo 100 SAE40. Do not use Delo 400, it does not meet the sulphated ash spec.
Mobil Delvac 1240 SAE40
Chevron/Texaco Ursa SAE40 Super Plus
There may be others out there that will work, contact your local oil suppliers until you find one that can supply an oil that meets the specs.
Detroit engines have very specific requirements for engine oil, mainly two, 1) use only SAE40 oil, no multigrade. If you're in an extreme northern climate you might use SAE30 in the cold of winter, but it's better to use a block heater to help keep the oil warm and use SAE40, and 2) the oil must have a sulfated ash content of 1.0% or less, the more less the better. Any oil 1.0% or above does not meet the engine oil specs.
This stuff is critical for the life of these engines. Use of the wrong oil, or use of multigrade 15W/40, will result in increased oil consumption and damage to the pistons and liners causing shorter engine life.
A few oils that meet the engine specs:
Chevron Delo 100 SAE40. Do not use Delo 400, it does not meet the sulphated ash spec.
Mobil Delvac 1240 SAE40
Chevron/Texaco Ursa SAE40 Super Plus
There may be others out there that will work, contact your local oil suppliers until you find one that can supply an oil that meets the specs.
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