Timing chain tensioner leaking

I too is having this issue. The service centre checked and said timing chain tensioner is seeping. I bought the gasket and would like to DIY changing the gasket. However, cannot find any instructions on how to do this. Do I need to re-align the timing chain when taking out the tensioner? Anyone have full instructions? Appreciate any help.

 

The first video linked in this thread goes into some detail, towards the end, during the reinstall process.

New head gasket replacement video from Gasket Masters | PriusChat

 

You push the plunger of the tensioner in and set it with the hook on the pin... That much I'm sure.

I may have missed it in that video, but I think the rest of the process is documented better in the first HG video (second video posted in that thread). Once installed you pull one of the timing gears till you hear a click then go the other way till you hear a click. 36:25 on the old video. I assume this is what releases the hook on the tensioner, but I'm not sure.

Can anyone confirm that that second process above is correct?

 

IIRC someone here was also talking about a trick involving a wire? I might have even salted away a link, will look.

 

Ok, here are the information I gathered on replacing only the timing chain tensioner gasket.

- No need to open the timing cover. Just unscrew 2 bolt on the tensioner.
- Replace the gasket.
- Before putting the tensioner back, push the tensioner all the way in and click the hook on the tensioner.
- Put the tensioner back and screw the bolts.
- Turn the chain anti-clockwise (by turning the crank) until you hear a click which means the tensioner was released.
- done.

What I am not sure is that can you turn the crank anti-clockwise? Isn't it dangerous to turn crank anti-clockwise as it will screw up the engine timing?

BTW, do I have to drain the engine oil first?

 

One thing I do know for sure: you are well above the oil line, no need to drain oil. The oil would only be leaking out of there when the engine is running.

Hopefully someone can confirm the rest.

 

This is from the manual. Err..are we able to "check that the plunger is extended"? Aren't the plunger inside the engine/timing chain?

 

I saw that a day or two back, but could not remember which thread had posed the question, lol.

They've still got the valve cover off (in the illustration case), maybe they're thinking to look down from above with a light.

In your case, listen for a sound?

 

I have done it!! Was kinda scary as I have problem turning the crank. It was tight! I didn't dare to use too much force as it seems to be tight after cranking for around 90 degree.

The first time when I put it in, I wasn't sure if the tensioner ejected. So I took it out and put it in again. Second time, when I crank anticlockwise, I did hear a click after around 45 deg of turning. Then I turn clockwise but it was tight! Made it through around 90 deg and it became very tight. So I stopped and start the car. Well, everything seems to be running fine after 5 days now. Haven't check if the seepage is still there.but I don't care anymore unless it is dripping bad.

 

Thanks for the hands-on info.

That is funny!

 

Glad it worked, and thanks for the report.

I'd say, though, that turning counter clockwise by 45 degrees is a lot more than the "counterclockwise slightly" specified in the instructions. Sounds like no problems were caused, though.

In general, the main reason you don't want to turn an engine with a timing chain CCW is the potential for damaging the chain tensioner or chain guides (typically plastic). Usually, when it turns CW, the crank is driven, the chain is pulled tight and pulls the cam(s), then a chain tensioner takes up the slack between the last cam and the crank sprocket. All good.

But if you were to turn the crank CCW, that last segment of chain would become tight, which would put force on the tensioner, which may be a lot more force than the tensioner sees when it's doing its job with the engine rotating CW. So that's the danger. In normal CW operation, that segment of chain is only as tight as the tensioner makes it = well controlled. When driven CCW with a wrench on the crank, it is as tight as it will get based on the cam(s) resistance, which may be a lot higher, which may be enough to crack the chain guide or damage the tensioner.

Per the instructions, it is exactly aimed at moving the crank sprocket so it moves the chain so it affects the tensioner, in a very specific way. So I expect it is well considered and safe to do that, but would have been better if they quantitatively specified what "counterclockwise slightly" means.

 

I just identified this same issue with my Gen III. Very slight seeping. Always thought it was coming from the oil pressure switch, but it looks like the block is wet around the timing chain tensioner cover/backing plate.
It appears that Mahle has a timing chain gasket set that has the appropriate gasket (Part No. JV5188).
I also found a gasket through Advance Auto - OES Genuine Chain Tensioner Gasket A5160466157OES
*Note: I would rather replace the gasket than use gasket maker.
Does anyone have the Toyota part number? I can't find it on any parts diagrams. Is it not available or does it only come with a new tensioner?

Also, I know, that the manual says to turn the engine anti-clockwise, but I have always been told that you should only spin an engine the way that it naturally turns? Thoughts?

Additionally, Toyota Maintenance Youtube channel has the replacement done on a Corolla (same block) and he turns it clockwise.

 

I think I answered my own question:
Toyota Part No: 135520T020
Is this correct?

 

For mine, the parts number is 13552-37010

 

Thanks!

Looks like that part number has been superseded by 135520T020.

 

I see that seep very often on corollas and gen3s- it's right where the timing cover, cylinder head, and block all meet. (I call it the corolla triangle). I have resealed the timing chaing tensioner on a couple of cars with no change to the seep. I have never seen anything more than a slow seep, and so I can't really reccommend repair as the amount of labor needed is quite high, and I can't be sure that the problem is only the timing cover sealant and not the head gasket.

Posted via the PriusChat mobile app.

 

Yeah, I can take a picture of mine, but its definitely seeping from the tensioner. There is no other oily build-up on the block accept from that point.