Car Talk: If you take your chances, it could cost mom even more money

Dear Car Talk:

We recently had my parents’ 2013 Honda Odyssey minivan in the shop for a state inspection.

It passed with flying colors, but the shop recommended my mom replace the timing belt and water pump since the car has almost 90,000 miles on it and is 11 years old. The van is wheelchair accessible for my 92 year old father, but we only drive it once or twice a week for short trips (5-10 miles).

The shop said if the timing belt broke it would ruin the engine. Replacing the belt and pump costs $1,300. My husband says we should take our chances and save Mom’s money.

What do you say, mighty motor guru? By the way, I don’t know anything about cars, but I really enjoy reading your column. – Mimi

Thank you, Mimi. I don’t know anything about cars either, but I enjoy writing about them.

Your mechanic is right. You might save your mom $1,300 now, but it could end up costing her $8,000 if the belt breaks and the motor breaks. And that’s exactly what would happen. Therefore, even the most basic cost-benefit analysis will boil down to making this particular repair.

Now, is it possible for the timing belt to stay good for the next 25,000 miles? Yes, it is possible. But the recommended replacement interval, in my opinion, is every 105,000 miles or every seven years. And you are near one of them and far behind the other. So you take a risk.

This Odyssey uses a common design called an “interference engine.” It is a very fuel efficient design, but is made more efficient by the open valves and piston sharing space in the cylinder. And it all works perfectly as long as they don’t try to share the same space at the same time.

What controls that? The timing belt. So if the timing belt breaks or jumps, the piston reaches top dead center and collides with the valves that are currently open. And that’s goodbye, engine.

To change the timing belt, you will need to remove anything blocking your access to the water pump. That’s a lot of stuff. And since you’re already paying the labor cost of exposing the water pump, it’s silly not to replace it at the same time. Especially since it also has 90,000 miles on the clock.

If the van is otherwise in good condition, I would tell mom to bite the bullet and make the repairs. If she just drives by mileage and drives 20 miles a week, she won’t have to change the timing belt again until 2125. So tell her I recommend she do the repair now and then plan on replacing the timing belt in 2124.

Do you have a question about cars? Write to Car Talk, write to Ray in care of King Features, 628 Virginia Drive, Orlando, FL 32803, or email by visiting the Car Talk website at www.cartalk.com.