Timing Belt broke at 65 MPH. How do i assess damage

2011 Honda Pilot. 180K miles: Timing belt was replaced 50K miles ago. It has just broken at highway speeds. How do I assess the degree of damage and if vehicle is worth getting repaired?

How do you know the timing belt broke if the damage hasn’t been assessed by a professional?

Starter motor spins but no motor movement. Checked compression. None.

Then I’d start by looking to see if your car has an interference engine (using google).

There are two types of interference engines: piston-valve interference and valve-valve interference (on a v-6 or v-8 engine). If your engine has either one, it’s toast.

If it’s not an interference engine, pull the valve cover and see if you can spot any damage or have a mechanic check the valves.

Unless the engine is the 3.0 or 3.2 liter engine, which are non-interference, there’s probably bent valves, at least.


Timing belt should last over 50k miles.

It probably is an interference engine. There are rare circumstances where - when a timing belt breaks on an interference engine - there is no damage…but those are extremely rare. Have a trusted mechanic evaluate the it. I’d also be checking with the mechanic who did the timing belt 50k miles ago…Might have put it on too tight causing a premature failure.

It wouldn’t hurt to see if there is some kind of warranty, but whether the mechanic was at fault or not, don’t expect him to admit it might be a possibility. Any number of factors can lead to premature failure of a timing belt.

This is VERY confusing. Do you mean the motor doesn’t start? Or that the motor doesn’t turn over?

I interpret that as “starter motor spins but no engine movement”

The vehicle has the 3.5 liter V6 and it is an interference engine. Agree it is likely the valves are damaged. Just wanted to see if anyone had experience with same problem. I am trying to discern if it is worth the hundreds of dollars just to have engine thoroughly examined to see if it salvageable. Thx

Does the engine turn over when you try and start it? If the starter spins, but the engine doesn’t, then the starter is bad.

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I’ll bet the engine is spinning…but just the bottom half.

I suspect a belt as opposed to a starter just for the fact it died on the highway. If starter then there would have to be two different problems. One - why the truck died…and two - starter.


The starter is fine. It spins. Failure of engine occurred while cruising. It was sudden loss of power

Does the engine seem to spin over faster when trying to start it?


There is no engine movement. Starter spins very fast

If the crankshaft isn’t turning perhaps the torque converter drive plate broke.

These statements contradict each other. If the starter is spinning then the engine should be turning (at least the crankshaft and pistons). Just because the starter is spinning doesn’t mean it’s OK. The starter also has to engage the fly-wheel.

These are the following possible scenarios.

  1. Starter IS spinning and engaging fly-wheel and bottom half of engine is turning over. - Timing Belt problem.
  2. Starter IS NOT spinning. - Possible starter problem and something else since the vehicle died while driving.
  3. Start is spinning but is NOT engaging fly-wheel. New Starter.

Remove the spark plugs, Insert a screwdriver or dowel rod into one hole. Rotate engine by hand from crank bolt. See if you have piston movement. If you do, then next step is more involved. Gain access to timing belt area/camshafts. Rotate cams/crankshaft as necessary to close both intake and exhaust valves in a cylinder and then do a leak down test on that cylinder. Repeat for all cylinders. If all test OK, then maybe worth investing in new t-belt. If not (and most likely) you have some bent valves and or piston damage. Only way is to remove heads and inspect. Good luck.

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Thank you TwinTurbo. Very useful advice.

MikeInNH: I am now convinced dealing with scenario 1.

Guess now i need to decide if a motor with 185K miles is worth pulling heads or just go replace the motor

Thanks to all. Going to tow to a my friendly neighbor mechanic

Keep us informed as to the outcome. We’re always curious to learn exactly what the problem is/was. Kinda like Stump-The-Chumps

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