November 20, 2017

Cambelt – what does it do? The “technical” part

The timing belt is essential to the operation of your car’s engine.  There are two main “shafts” in your engine, the Crankshaft, and the Camshaft.  The timing belt connects these two shafts and makes them turn together at the right “time”.  This is like the way a bicycle chain connects the pedals to the back wheel.  This makes sure all the other goodies in the motor (like valves and pistons) are jumping and hopping at just the right “time”.  Hence the name “…timing” belt.

What happens when it breaks?

The timing belt is made of rubber, eventually it rots, and breaks.  When this happens, your car stops. You need to get the car towed because it won’t start until the engine is “re-timed”, and the belt replaced.  With some cars you can replace the belt and that’s the end of it, with other cars, it’s just the beginning of sorrows…


The “Valve Benders”

Some engines have a very close fit between the top of the piston and the bottom of the valve.  When the engine is “in time” this close fit is just fine, because the piston is never up at the same time that the valve is down.  BUT, when the timing belt breaks, the valves stop moving.  Some of them are in the down position, and the piston, not aware of the little valve’s predicament comes flying up and SMASHES into the poor little valve.  The valve gets all bent out of shape over this and decides not to let your engine have any compression in that cylinder.


Life with a bent valve

Even if you replaced the timing belt at this point, the engine would still not run right, it would be very weak, and probably cough and hack because of the bent valve’s poor health.  You basically “have to” fix this condition or shoot the car to put it out of its misery.


In order to fix this, a “valve job” is required which could be very costly.  Depending on the make of your car, and on how many “extras” are discovered that you need once the engine is torn apart.  The “good news” is….

You can save the little valves!

All you have to do is replace the timing belt when it’s due, instead of waiting until after it’s dead.  The cost may be high, but it’s a whole lot cheaper than waiting for it to break.


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