Natural gas engine oil

[genie47]

I am now considering converting my car to use natural gas.

I know it runs leaner at an AFR of 17:1 compared to gasoline. This will lead to higher temperatures. Not only that, I know that gasoline actually lubes the valve seats and with a gaseous fuel this will lead to premature valve seat failure.

The question on my mind is this: Do the modern SM/GF4 rated PCMOs lube an engine that runs on CNG effectively.

 

[Geoff]

As I recall you need a low "sulphated ash" oil for natural gas engines. Most of the oil company sites (Chevron, Mobil, BP, etc) have information on specific formulations and ratings.

 

[Trex101]

My brother in Australia is using HDEO 15w40 oil for this 3.5L Mit Magna (dual fuel). There's no recommendation on which oil can or cannot be used but it's recommended to switch back to petrol once a week for longer valve durability.
The latest Tartarini sequential vapour injection will solve this problem as it will switch back from gas to petrol under hard acceleration or during cold start.

 

[DieselPower]

Most oil manufacturers do make a L.P. & Natural Gas engine oil. It is more for stationary engines though. It is a low ash and no viscosity index improver oil. In a car converted to L.P. or Natural Gas the only thing I would suggest is using a low ash oil.

 

[dwendt44]

The forklift mechanic that maintains them at work uses plain old auto oil.
It comes out as clean as it went in.