Timing chain tensioner oil seal leak

Toyota Corrolla, 2008 with 152,000 miles. Timing chain tensioner oil seal leaking. No drips on the garage floor; does it need to be replaced? What is likely to happen if it is not replaced? Will replacing it cause other old seals to leak?

How do you know the tensioner is leaking?


The dealer said it was leaking. I don’t know where to look myself to verify that it is leaking. It is not leaking enough to drip on the floor.

It’s usually the tensioner O-ring that starts leaking.

The leak may not be bad enough to leak oil on the floor yet. But if the leak gets large enough to where the tensioner no longer applies the proper pressure to the timing chain tensioner guide, it can cause the timing chain to jump teeth on the timing gears. And you don’t want that to happen.

Ask the dealer how much it would cost to just replace the O-ring on the tensioner.

The timing chain tensioner is mounted on the side of the engine. And looks like this.


Get a second opinion from a trusty independent shop. Dealers want to return cars to original brand new specs or so has been my experience. The minute you are out of warranty they will want to change your shocks for example.
Your leak could be a minor seepage that just would need close monitoring, or not.

The dealer quoted $182 dollars to replace the oil seal. Are they just replacing the “o” ring or do they replace the tensioner itself?

Your pictures are really helpful. I’ll check the engine to see if I can tell how much it is leaking.

It’s called an O-ring seal.


The dealer quoted $182 to replace the O-ring seal. Do you know if that is reasonable?

Ray , why not get a second opinion and this is not a necessary dealer type repair . Any independent shop can do this and should be cheaper.

This O-ring leak is a common problem with this engine.
It starts out slow seepage and gradually gets worse.
It’s located on the back og the engine block, passenger side.
A small hand mirror makes it easier to look.
I replaced it twice on my previous Matrix.
A 15-30 minute DIY job with a 10mm socket and ratchet wrench.
The O-ring costs a couple bucks from the dealer.

Thanks for the tip about the mirror and the location ( back of engine block on passenger side ). I’ll try looking again because I could not find it among all the hoses and attachments the first time I looked, not knowing where exactly to look.

What can go wrong on a DIY job? Will a lot of oil leak out when the tensioner is removed? Does it just slide out easily?

Thanks your information is very helpful.

Here’s an image showing location on back of engine:

Google to find instructions.

Hey ray44benoit_145408, any updates on this? Did you work on it yourself?

I did not want to create another thread and have a similar problem with my 09 Corolla S. So bringing this thread back on top. Any inputs / advice is welcome!

Long story - First a mechanic in the area (with good reviews online) said it was the crank shaft seal that’s broken and needs to be replaced. He gave me a quote of about 600 CAD.

I took it to Toyota for second opinion and they said it’s the timing cover that needs to be replaced and quoted 2000 CAD for the job! They also said it would take 2 days, taking off the engine block altogether and need to order parts ahead. Plus, there might be leak in the crankshaft seal too and that can be checked after the timing cover replacement. This would be additional 200 CAD at least.

So I started looking for answers and see if I can do it myself. First challenge is to find a place to do it as I live in a rented apartment and can’t do maintenance on the property. I am sure pretty much all public places around the city gonna restrict it citing safety & environmental codes.

ADS, Vancouver.

Those are both fairly major jobs best left to an experienced wrench turner with a full set of tools and proper workspace.

How bad is the leak?
If it doesn’t leave a small puddle where you park or make the oil level drop I’d leave it be and drive on for now.

Thanks for the response! I don’t see any oil spill and keeping an eye out for it.

The crankshaft seal is really pretty easy to replace. It goes into the timing chain cover and the dealer wants to replace the whole cover instead of just the seal. That is not needed.

The trick is to find or make a tool to hold the engine pulley from turning while you loosen the crankshaft pulley bolt. I made one out of a piece of 1x4 wood and a couple of 8mm x 60mm grade 10.2 bolts. Pry the old seal out and carefully bang the new one in place.

This type of leak does not always show up on the ground. When this seal leaks, the pulley slings the oil outwards and you see the results all over the parts that are 90 degrees from the pulley, like on hte firewall, radiator etc.


Make sure to change the oil and filter per the manufacturer’s intervals (at least that often, preferably more often) once you get these problems corrected.