Engine Valve Wear

Engine Valve Wear.

A large majority of engines can be converted to LPG without any further engine modifications but some will show a degree of engine valve wear if converted to gas.

Autogas 2000 have a database of known engines and configurations that this occurs on so you can be sure of the best advise given at your first point of contact.

Engine valve wear occurs mainly due to an increase in combustion temperature while running on LPG. This temperature increase and also the material that some engine valves are made from means that untreated prolong running on LPG will result in either valve seat recession (more common on older engines) or general pitting of the valve and seat with reduced sealing. In both cases it’s important to check engine valve clearance and adjust where necessary but this on a modern day engine is either done automatically or through a general engine service as specified in the owner’s manual.

Engine valve wear can take time to show and a lot depends on the type of driving style as well. A high motorway user can expect to see a decrease in engine performance or poor idling at around 30,000 miles for example due to sustained fixed throttle engine speeds. If the car is a second car as used for shopping or more rural driving then it tends to be less affected the same way so the end user can expect a longer duration before noticing any engine valve detoration.

With any LPG conversion we have a number of tips to ensure that the engine valves are looked after.


JLM Valve saver kits


The most common is to install a valve lubrication system. There are a number on the market but we have used and endorse the JLM valve saver system as been the best choice.

This simple device can be installed at the same time as the engine conversion is done and once filled with the JLM valve saver fluid it allows a controlled mixture into the engine during running to further coat and lubricate the engine valves. You can read more about this process on the JLM valve saver page.


Software Options

Another option is built into some of our engine specific conversion software options on the LPG system where a form of split fuel is used. This means that while running on LPG a small percentage of petrol at certain engine loads can applied to help in valve lubrication while running on LPG.

In these cases the engine valve wear has been cheked at a manufactuer level to ensure the best possible protection