Engine oil consumption is actually a dilemma nobody desires. Most new engines at this time use much less than half a quart of oil in 3,000 miles. Some use virtually no oil. But since the miles accumulate, wear and oil consumption naturally go up.

Applying a quart of oil every single 1,000 miles isn’t unusual to get a substantial mileage engine. The quantity of oil utilized continues to be acceptable, but by the time it reaches a quart of additional in 500 miles it’s using a lot of oil. Blue smoke inside the exhaust is a traditional sign that an engine is burning too much oil.

Should really you be concerned? It relies on your spending budget, the value of your automobile, if you can afford to rebuild or replace the engine, and irrespective of whether the oil consumption is leading to other difficulties.

An engine that burns oil will generally foul the spark plugs. That, consequently will cause ignition misfire, increased emissions and likely harm the catalytic converter. Also, an engine that is certainly burning oil normally will not pass an emissions test as a result of elevated hydrocarbon (HC) emissions.

If an engine is using oil on account of leaks (valve cover gaskets, oil pan gasket, crankshaft finish seals, etc.), the issue might be fixed by simply replacing the leaky gaskets.

WHAT Leads to Extreme OIL CONSUMPTION

Oil consumption depends mainly on two things: the valve guides and piston rings. In the event the valve guides are worn, or if there’s a lot of clearance involving the valve stems and guides, or in case the valve manual seals are worn, cracked, missing, broken or improperly set up, the engine will suck oil down the guides and to the cylinders. The engine may possibly nevertheless have great compression, but will use loads of oil.
engine valve deposits

Worn valve guides can usually be restored a variety of unique methods. One well known strategy machine outlets use is always to ream out the guides and install thin bronze or cast iron guidebook liners. Knurling is another method which will lower valve guide clearances. With aluminum heads, the authentic guides is often driven out and replaced with new ones. With cast iron heads, the guides is often reamed out to accept new valves with oversized stems.

In the event the oil burning is on account of worn or broken rings, or wear within the cylinders, the engine will have very low compression. The only cure here will be to bore or hone the cylinders and replace the worn or broken piston rings

Oil burning can also come about if your cylinders within a newly rebuilt engine are usually not honed accurately (also rough or also smooth), or in case the rings are installed upside down, twisted onto the pistons, or the finish gaps are too massive or are usually not staggered to cut back blowby.

How to Cut down OIL CONSUMPTION

There are no “miracle” engine solutions or pills that will end oil burning. But some crankcase additives can slow oil burning. You will discover also “high mileage” motor oils which are specially formulated with further additives to slow oil consumption. Switching to a somewhat increased viscosity motor oil (say modifying from a 5W-30 to a 10W-30 or a 10W-40) may also enable cut down oil consumption.

If an engine is working with oil due to a leak, the leak has to be fixed to halt the reduction of oil. Valve cover, timing cover and oil pan gaskets are generally not as well hard to substitute, but leaky crankshaft finish seals can need a great deal of disassembly (especially the rear major crankshaft oil seal). One alternative to replacing a leaky gasket or seal is always to add some “seal conditioner” for the crankcase, or to switch to a “high mileage” motor oil that includes extra seal circumstances. The additives soak to the seals and gaskets, triggering them to swell somewhat. Hopefully, this will likely slow or seal the leak.

When the engine is working with oil due to worn valve guides or valve guidebook seals, it truly is doable to change just the valve guide seals without needing to remove the cylinder heads or overhaul the engine. New valve guide seals can drastically lessen oil consumption. I have witnessed engines go from employing a quart of oil just about every 500 miles to utilizing no oil amongst oil adjustments (3000 miles)!

Replacing the valve stem seals demands a specific valve spring compressor to disassemble the valve springs on every cylinder (one at any given time). Remove the valve cover and all of the spark plugs. The piston during the very first cylinder must then be positioned at major dead center. This could be done by rotating the engine with a wrench around the crankshaft pulley until finally the timing marks line up. In case the engine has no timing marks, insert a plastic straw to the cylinder throughout the spark plug hole so that you can truly feel the piston as it approaches top rated dead center.

The cylinder should then be pressurized with compressed air with the spark plug hole to stop the valves from dropping down into the cylinder once the valve springs and retainers are eliminated. One more trick for holding the valves in place is always to snake a piece of rope or rubber tubing into the combustion chamber through the spark plug hole when the piston is at major dead center. The rope will fill the void amongst the piston and valves to hold the valves in area whilst you change the seals.

Be careful, because if a valve accidentally drops down to the cylinder, the cylinder head could have to come off the engine.

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