Excessive oil consumption

then the engine may be burning oil. Burning oil may not be an immediate problem to worry about if your engine is a high mileage one. High mileage engines start burning more oil with time. If it hasn’t started causing other problems then it shouldn’t be an immediate attention seeker. Problems that usually arise with oil consumption are fouled plugs and consequently the irritating misfiring. Apart from that, oxygen sensors and catalytic convertors can and will be affected by an engine consuming a lot of oil. Sensors will get coated with oily residues and catalytic convertors will get clogged up and retard engine performance.

An engine that consumes oil is easy to identify because of the colour of the smoke from the exhaust. Blue smoke is almost a sure sign that your engine is burning oil. You’d need then to identify where the problem is coming from. Does it smoke continuously? Does it smoke after parking it for a while only? If the smoke goes away after running the engine for a while the problem may lie with the upper half of the engine, the cylinder head. It may possibly be worn valve guides or seals. It means oil drips into the combustion chambers when the engine is idle and gets burnt when you start up the engine. Such a car may misfire on first start up because of that.

On the other hand, if the engine rings are worn out you will find that the car smokes most the time, even after running it for a while. It means the oil scrapper rings are no longer sealing well and oil finds its way into the combustion chamber. A simple compression test can tell you how much life you have left in your engine. A simpler equation to help you ascertain goes like this . . . smoke under load usually points to worn rings, smoke with no load usually points to valve stem seals or worn valve guides.

Since vehicles with high mileage naturally consume oil more than lower mileage engines, it is good to change to high mileage oil which is specially formulated to lower oil consumption on older vehicles with high mileage.

Leaks as I mentioned earlier are easier to deal with and require one to replace the seals and gaskets with new ones. Gaskets lose their strength with time and need replacing over time. This does not really cost a fortune.

Valve seals and guides require specialist mechanics to replace. It may or may not cost a lot of money to replace valve stem seals depending on how the mechanic decides to do it. Naturally the head has to come off to replace the seals but there are shortcuts like pressurising the cylinders to keep the valves from falling into the chamber. It may keep the costs down if the mechanic is willing to go that route.

Worn rings mean one thing and that is major engine overhaul which might cost you a bit of money and has to be done right. Till next time . . . keep the wheels spinning!

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