Leaky chain tensioner

[lolcantturn]

I don't want to have to resort to BFc, thought you guys might have a nice answer to this

My chain tensioner is leaking. I replaced the crush washer (which just seems like a regular washer but ok)

The problem seems to be after the threads, there are "holes" (I don't know why there are holes) in the chain tensioner cylinder, as seen here in the OEM bmw one

http://www.pelicanparts.com/cgi-bin/smart/more_info.cgi?pn=11-31-1-703-746-M9&catalog_description=Timing%20Chain%20Tensioner%20Cylinder%2C%20E%33%36%20%33%32%33is%2FiC%2C%20%33%32%35i%2Fis%2FiC%20%28from%20%39%2F%39%34%29%2C%20%33%32%38i%2Fis%2FiC%20%20%20

This chain tensioner doesn't seem to have the "Holes" in it

http://www.pelicanparts.com/cgi-bin/smart/more_info.cgi?pn=PEL-1PC-1&catalog_description=%31%2DPiece%20Chain%20Tensioner%20Kit%2C%20Lower%20Chain%2C%20Replaces%20Original%20%32%2DPiece%20Tensioner%2C%20For%20Models%20with%20Fork%20Style%20Piston%2E%20Includes%20Tensioner%20and%20Sealing%20Washer%2C%20E%33%36%20%33%32%35%20%28through%20%38%2F%39%34%29

Regardless, what can I do to stop this? I've torqued it to spec of course as well. Perhaps I can jb weld the holes shut? I'm assuming the purpose of the holes is to lubricate the inside of the piston, but I'm sure it lubricates itself from just being exposed to the timing case.

[hwy84]

Google is your friend

Upgrading to the new style chain tensioner is old news and you should do it. Everyone should do it. Its a better designed part, less prone to failure.

Now, if you used a NEW OEM sealing ring (crush washer), and you torqued to spec (37 lb/ft for your old style, 30 lb/ft for the new style), you should have no leaks. The holes in your old style tensioner are critical to it's function - don't f with them. If you used the appropriate new crush washer, and you have leaks, you have a problem with the part itself, or you monkeyed the threads and you are hosed up good.

Does your timing chain rattle at idle-1500 rpm? If so, you need to replace that tensioner anyhow. If you did all the above correctly, and it still leaks - it's the stupid 2 piece design showing why it got updated. Get a new tensioner.

[lolcantturn]

Upgrading to the new style chain tensioner is old news and you should do it. Everyone should do it. Its a better designed part, less prone to failure.

Now, if you used a NEW OEM sealing ring (crush washer), and you torqued to spec (37 lb/ft for your old style, 30 lb/ft for the new style), you should have no leaks. The holes in your old style tensioner are critical to it's function - don't f with them. If you used the appropriate new crush washer, and you have leaks, you have a problem with the part itself, or you monkeyed the threads and you are hosed up good.

Does your timing chain rattle at idle-1500 rpm? If so, you need to replace that tensioner anyhow. If you did all the above correctly, and it still leaks - it's the stupid 2 piece design showing why it got updated. Get a new tensioner.

I indeed did everything correctly, new crush washer from the dealer, torqued it to spec. I put a new spring in it, there are no rattles at all. The tensioner is the original for sure. I will try again and clean both mating surfaces, the timing case and the tensioner, and see if it will seal better.

Good information though, I couldn't find much on a leaky chain tensioner.

[hwy84]

I indeed did everything correctly, new crush washer from the dealer, torqued it to spec. I put a new spring in it, there are no rattles at all. The tensioner is the original for sure. I will try again and clean both mating surfaces, the timing case and the tensioner, and see if it will seal better.

Good information though, I couldn't find much on a leaky chain tensioner.

Sounds like you're on the right track.

If it helps, I remembered that I am all chain tensioner'ed out because I used to have an S14 and an M42 - both of which suffered from tensioner woes. If you search around about those engines, you'll find more info out on various forums and sites.

[lolcantturn]

Sounds like you're on the right track.

If it helps, I remembered that I am all chain tensioner'ed out because I used to have an S14 and an M42 - both of which suffered from tensioner woes. If you search around about those engines, you'll find more info out on various forums and sites.

You had a leaky tensioner on your S14 and M42? Did you resolve it by updating to the 1 piece design?
There are some threads on S14.net that explain of some guys experiencing leaky tensioner when using an E36 one, but they all were dead ends/no resolutions.

[328ijunkie]

Those holes are there for oil flow