Is Mechanic to Blame for Timing Belt Woes?

Dear Car Talk

Dear Car Talk | Jan 21, 2014

Dear Tom and Ray:

I recently had to have a new water pump put in my 2005 VW Bug. At the same time, they replaced the timing belt. Twenty-three days later, I was stranded because the timing belt broke. After they examined it, they found that the crankshaft pulley was in many pieces, some of which were missing. Of course, they take no blame for this and say it was unrelated. What do you think? Did they break the pulley when they replaced the timing belt?

-- Kaylyn

RAY: They might have. I'd have to say it's extremely unlikely that a broken crankshaft pulley would break the timing belt, though. It's possible ... if it broke in a jagged way and tore through the plastic timing belt housing that sits behind it. Possible, but not very likely.

TOM: So let me put a more-likely scenario on the table. Perhaps what really broke was the timing belt sprocket, Kaylyn. It sits directly behind the crankshaft pulley.

RAY: To investigate, the first thing you need to do is check your receipt to see if they replaced something called the "front engine seal."

TOM: Normally, that seal gets replaced when you do a timing belt. Not always, but if you want to do a thorough job, you replace the front engine seal and the water pump whenever you do a timing belt job.

RAY: Why? Because both of those parts are relatively inexpensive, and they're easy to access once the timing belt is off. And if either one fails, say, three weeks later, you have to do the timing belt all over again.

TOM: Which, as we've found out, makes our customers extremely grouchy. So we never change a timing belt without also changing the water pump and the front engine seal.

RAY: But in order to get to the front engine seal, both the timing belt sprocket and the crankshaft pulley have to be removed. And that's not always easy, especially on VWs.

TOM: So if they had to use force to pull off the sprocket, they could have put a small crack in it. Or if they used heat to loosen the bolts that run through the pulley and the sprocket, and accidentally overheated them, they could have weakened the sprocket's metal and caused it to fail a few weeks later.

RAY: So look at your receipt, Kaylyn. If it's illegible or indecipherable, ask some other mechanic to help you read it (if you want to find an honest mechanic, try the customer-generated listings at

TOM: If your shop charged you to replace the front engine seal, then I think you have a right to be suspicious. And since what you need now is major surgery, I think a second opinion is called for.

RAY: I'd search the Mechanics Files for a trustworthy mechanic in your area, and have the car towed there. Tell him what the other shop told you, and ask him to look at the car and see if their story checks out.

TOM: The second guy may tell you there's no way to know exactly what happened. Or he may confirm our theory. Or he may have a theory of his own that either exonerates or convicts these other guys. Ask him to write up his professional opinion for you. You'll have to pay him for his time, but I think it's worth it, in this case.

RAY: Armed with that information -- and expert witness testimony, should you need it -- you can go back to the original guys, if warranted, and suggest, a little more persuasively, that they do the right thing for you and fix the car.

TOM: All reputable shops carry Garage Keeper's Liability insurance (what we call "Bonehead Insurance") to cover serious mistakes they make on customers' cars. So they probably have the means to repair this if they need to.

RAY: And if they continue to tell you to go sit in your hat, you'll have to decide whether it's worth taking them to small-claims court over this. But at least you'll be better prepared to win. I hope it doesn't come to that. Good luck, Kaylyn.

Get the Car Talk Newsletter

Got a question about your car?

Ask Someone Who Owns One