Bent Valves and Other Common Issues After a Timing Belt Snaps | YourMechanic Advice

Bent Valves and Other Common Issues After a Timing Belt Snaps

Ignoring your timing belt can come with a high cost. Timing belts don’t often snap, but when they do, it can cause piston damage, ruined cylinder heads, and engine valve damage.

Probably, when you think of your engine, you picture the valves and pistons, but you don’t think much about what keeps them in good working order. Let’s state it plainly – nothing is more important than the timing belt. It drives the camshaft, which is what keeps the valves synchronized, and the crankshaft, which controls the pistons. Your timing belt tells the pistons when to rise and fall, and the valves when to open and close.

How to tell if your timing belt is bad

Timing belts don’t often give you a lot of warning when they’re about to give way – they might squeak or chirp, or they might just suddenly break. More often, though, damage is due to wear in the timing belt. You can do a visual check – see if there’s any cracking, glazing, missing teeth or oil contamination. Or you can have a mechanic check the belt for you. Most vehicle manufacturers also recommend that you make timing belt replacement a part of your routine maintenance, replacing it every 60,000 miles. Some belts are good for up to 100,000 miles. If you’re in doubt, check your owner’s manual, or ask your dealer or mechanic.

Interference vs. non-interference engines

The level of damage caused by a broken timing belt can depend on the type of engine you have in your car. A non-interference engine provides clearance between the valves and pistons, so if the timing belt breaks, you might end up with bent valves, and you might have to have your cylinder heads rebuilt, but the engine isn’t likely to be destroyed.

With an interference engine, though (and about 70% of the vehicles on the road today have this type of engine), the pistons and the valves move within the cylinder – just not at the same time. The pistons and the valves “own” the cylinder at different times. Here’s the thing, though – the period of time between “ownership” can be less than a second. If the timing is off, be it less than a second, there is nothing to stop the pistons and cylinders from colliding. This throws the rods off, and they start to poke holes in the engine block. Eventually, the engine simply cracks in half, and there’s no way to repair it.

Now you know the disastrous consequences of neglecting your timing belt – engine valve and piston damage, bent valves, cylinder heads that need to be rebuilt or replaced, and possibly even total engine destruction. If you don’t want to see those dollar signs adding up, check your timing belt regularly, and have your mechanic replace it on schedule.


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Recent Timing Belt Replacement reviews

Excellent Rating

(1,217)

Rating Summary
1,140
41
6
6
24
1,140
41
6
6
24

Eddie

39 years of experience
16 reviews
Eddie
39 years of experience
Honda Civic - Timing Belt Replacement - Star, Idaho
Eddie knows what he's talking about. He's gone above and beyond what is expected oh him. He didn't wash his hands off of my vehicle when it was giving him the greatest grief. He persevered through in getting my timing belt replaced.
Subaru Forester - Timing Belt - Meridian, Idaho
Upstanding job, Excellent service. Mr Eddie is very Efficient, friendly and professional . Highly recommended.

Jimmi

26 years of experience
102 reviews
Jimmi
26 years of experience
Hyundai Santa Fe - Timing Belt - Orlando, Florida
Great mechanic very knowledgeable and informative. knew how to disassemble and reassemble timing belt on Santa fe.
Hyundai Sonata - Timing Belt - Orlando, Florida
Jimmi was quite knowledgable and took great care with my vehicle! Additionally, he gave me an honest and detailed explanation of future preventative maintenance, including what was important and what needed to wait.

Victor

34 years of experience
148 reviews
Victor
34 years of experience
Honda Odyssey - Timing Belt - Albuquerque, New Mexico
He stayed beyond the appointment time to make sure my car was running they way it should. Friendly and professional.
Toyota Sienna - Timing Belt - Albuquerque, New Mexico
Victor arrived on time and finished the job ! Great service, I just made another appointment with him!

Caz

16 years of experience
27 reviews
Caz
16 years of experience
Honda Accord - Timing Belt - Atlanta, Georgia
Deven was right on time and was very professional. I think he did excellent work and I was very satisfied.
Toyota 4Runner - Timing Belt - Acworth, Georgia
Deven was very professional and completed the timing belt replacement within the scheduled time. He pointed out to me that the rear brakes did not require replacement at present. I’d schedule Deven again for future maintenance.

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