3) Tensioner is located in not so visible and pretty tight space, so I'm wondering how did you guys access it. Did you go through the top or from under the car?

4) Should I just buy Tensioner and Belt from Toyota dealer? Or are there reputable aftermarket parts for these?

Thanks in advance.

You can access it from top. Feel for the studs with your fingers while taking off and putting it back together. Very little chance of messing up anything.


Replace just the o-ring on the tensioner (part# in the DIY) and you should be fine. For the belt don't use the Toyota one. To quote Hardtop - "It is HIGHLY advisable to NOT go with an OEM Toyota/Bando drive belt. They are known to stretch and squeak in as little as 20K miles. " The sticky Maintenance thread gives a list of belts you can buy. I am using Gates brand belt. Not a whisper from the belt here. Do this after the oil leak is identified and handled. You dont oil to get on the new belt.

 

It's hard to determine now because you let it get too far... Start by replacing the tensioner o-ring, and clean off engine and alternator. Then you'll see if it's still leaking.

 

I know this thread is 5 years old but did you ever figure out where you oil leak was originating from? I have had very similar problems and difficulties locating leak. I replaced tensioner, cam shaft seal. Still leaking some where above power steering pump and tensioner…

 

Valve cover gasket.

2004 TOYOTA COROLLA 1.8L L4 Valve Cover Gasket | RockAuto

 

The timing CHAIN tensioner has a common o-ring leak problem. It's not hard to replace, but for anyone reading this who has a similar problem, you want to make sure the bore into which the timing chain tensioner fits is 100% clean. Use something like a round "bottle" brush and a solvent to clean that bore. Use a mirror and light to make sure you've cleaned off ALL of the varnish. It's not necessary to replace the entire timing chain tensioner (just replace the o-ring and use the Toyota brand).

The serpentine belt tensioner can also leak and is known to go bad, but I doubt that is causing all the leak mess the DS (Discussion Starter) had back in 2017. At 423K miles I still have the original serpentine belt tensioner and timing chain tensioner.

I suspect the DS's problem was the front crank seal and most probably the timing cover seal (it uses a FIPG type of sealant). Both of those seals were leaking on my Corolla. Made a mess at the alternator, just like the DS had. While getting my inspection sticker at the Toyota dealer, they said my timing chain cover was leaking. They wanted something absurd, like $1400, to reseal it. No way I'm going to pay that, so I did it myself for the price of the sealant. I used Permatex Grey sealant "rtv"/FIPG or whatever it's called. I let it cure for about 20 hours before I put oil in. I didn't replace the original water pump, but I replaced the o-ring for the water pump (even though it looked fine).

For anyone dealing with this, spend the extra few bucks and purchase the Toyota brand of front crank seal.

The front crank seal leak will cause a big greasy residue on the plastic undercover right below it. The timing chain cover leak will get oil all over everthing, especially at the front of the car, like on the alternator.

 

 

Had a bad oil leak. Replaced crank shaft seal and timing chain tensioner (new) about a month ago. Two weeks later while replacing power steering pump I noticed more oil coming from the new tensioner. Thought I had cleaned the bore pretty well. Anyways I pulled it out and cleaned it off with degreaser. Then i put a bead of the red high heat gasket maker around the tensioner base and reinstalled. Hasn’t leaked since.

 

Question please=--
You mentioned about using permatex gray sealant.
Did you only degrease the area and apply permatex or did you go thru the whole 15 or 20 steps to replace the timing chain cover gasket?
My 2005 vibe has a oil leak that is difficult to deal with. Thanks for any advice.