timming belt replacement on a Prius??

No, it is a chain. Does have a water pump belt though.

 

Most replace it when the water pump is changed. Not sure on the actual time or mileage. If you see a lot of cracks on the inside (grooved side), it would be a good idea to change it.

Patrick Wong has documented the pump and belt change here on PC. A google search should reveal it for you.

Look on the passenger side up front under the hood. You should be able to see the belt plainly.

 

Note that Gen-3 eliminated it. Starting with the 2010, Prius became belt free... one more thing to add to the reliability. Gen-2 introduced electric A/C, which eliminated that belt.

 

The Gen 2 and 3 Prius' have a timing chain that turns the two cams in the cylinder head. The only belt that the Gen 2 Prius has is the drive belt for the engine water pump. The Gen 3 has an electric engine water pump.

 

Were you asking about replacing the timing chain? It's a lifetime chain with no replacement interval.

 

If your timing chain stretches enough, it will make a metallic noise, and it will be time to replace it. At a guess, near 250,000 miles it might start to be a worry.


On the left, the chain follows a tensioner arm, which allows for mild stretching of the chain. The chain guide on the right is passive.

 

From a mechanical stand point, there is NO timing chain out there that NEVER has to be replaced. To expect the chain would never need replacing is not good thinking from a mechanical stand point.

 

If you have over 100k miles, I would buy a water pump belt and store it with the spare tire. This way if it every breaks, at least you have the belt (and any mechanic can install it).
BTW, mine is still original at 356k miles, but has quite a few cracks in it.

 

Trying to set a record, 200V? Not worth it IMHO. The drive belt on my wife's Chevy Malibu broke last year when she was 30 miles from home. I put a new one on where it broke down (in a restaurant parking lot) and had to jump start the car as well. The belt had deep cracks and finally failed after 199K miles. I never looked at it or even thought about it LOL!

 

Is this similar on an 02 Gen 1 prius? Got some ticking at times on right side. Car has 433K. Never any engine issues

 

The Prius has solid mechanical bucket lifters, without shims or hydraulics. I would suspect that the valves are out of adjustment. Just a guess.

For a Prius I think you order new buckets. Sorry. (you can try the trick of reusing another bucket that doesn't fit their valve)

The lifters are available in 35 sizes in increments of 0.020mm

Toyota calls them Camshaft Folowers, here they are for a 2002 Prius

Valve Train Components for 2002 Toyota Prius | Toyota South

Item 12 in this drawing

 

Hi. The ticking sounds like a lifter but is only heard at speed . Fades when applying acceleration.Quiet at idle or slowing and seldom heard under load.
Thanks for quick response

 

It is hard to hear ticking over the internet. <G> I hope you find the issue!

 

Yes, tappet noise is getting louder, will try to record and pinpoint in time.
Thank you

 

At 433k miles valve noise is the least of your problems. Good run though.

The water pump belt should be replaced at minimum 100k miles proactively
If it fails water pump no longer turns you’ll never know till you see the engine over heat icon pop up on the dash and too late usually lunches the aluminum head. All over a $10 belt.

Really poor design no temp gauge.

 

This is one reason to get an OBDII reader that shows gauges, the sender there and working, just not displayed.