Chain tensioner question

[ebida3]

Can you stave off timing chain guide wear by replacing the tensioner?


I would imagine that the tensioner has lost a majority of it's tension after 12 years. By replacing the tensioner can it be beneficial to the system?

This way the chain won't beat against the guides due to proper tension.

[007008]

I believe No. You might reduce the slack and therefore noise, but the fact is the plastic on the guides are worn and will continue to wear.
http://i62.photobucket.com/albums/h93/16valvedcaddy/007_zps9c8b5edc.jpg (http://s62.photobucket.com/user/16valvedcaddy/media/007_zps9c8b5edc.jpg.html)
This is the bottom of the U-guide, its suppose to be one level.

[ebida3]

Wouldn't it keep the chain from beating against the guides if the tension was taken up the slack?

[sealbeach740]

Wouldn't it keep the chain from beating against the guides if the tension was taken up the slack?

+1.

I have no actual data, but this is why I've replaced mine. Cheap insurance when you consider the cost of repairing timing chain guides (or worse).
I would think chain slack would bang against the guides if the tensioner isn't doing it's job correctly any more.
Again, just my $.02, no real info to verify this with.

[IcemanBHE]

A little note of interest...

BMW changed the spring tension a few years back...and I wonder why they did that? humm...


So I would have to assume it does have some bearing on guide life. I replaced mine...

[Sobek]

Looking at the shape of the guides and the way the chain is routed, I don't see how a properly functioning tensioner could REDUCE wear. If anything, it would tension the chain more tightly against the guides, probably accelerating wear to some small extent.

- - - Updated - - -

Looking at the shape of the guides and the way the chain is routed, I don't see how a properly functioning tensioner could REDUCE wear. If anything, it would tension the chain more tightly against the guides, possibly accelerating wear to some small extent?

[THIRDGEN87]

look at it this way, new parts are always better than old.

[COOPERDB]

http://forums.bimmerforums.com/forum/showthread.php?1978327-Chain-tensioner



Use the search feature at the top of the page ---

[AquilaBMW]

I will be replacing these on my cars. I thought FEBI was the brand to go with. We all agree they are great for things like the CPS and Cam Sensors, etc. Autohaus AZ has them for $49+, I'll be ordering two so that's free shipping which I usually get in three days.

http://www.autohausaz.com/search/product.aspx?sid=blzreu5511myj4b1hb5y1pmd&partnumber=11%2031%207%20531%20813

[Timm]

The chain tensioner is hydraulic - the spring allows the tensioner piston to extend and take up more oil. It is the hydraulic action of the tensioner that is important - the spring (even when new) is too weedy to do much work. And that is where the problems come from, the piston either sticks in the cylinder (as one of mine did) or the parts wear so that there is little or no hydraulic action.

Once the hydraulic action is compromised the chain will slap the guides until they disintegrate. Also, where there is wear, the oil leaks from the tensioner when the engine is switched off - and when you start it up again the chain will rattle around the guides, and that does them no good at all. How many times have we heard a member say that the car was fine when it was parked up, but the next time it was started it sounded like a bag of nails. That is due to wear, the oil was lost, the chain thrashed around on startup, and that was the end of the guides.

Although the guides will wear and fail eventually, if you don't change the tensioner when you get start-up rattle, they won't wear out, they will be flailed to death!

[IcemanBHE]

Let me clarify...

I KNOW the spring tension increased. But I dont know if they changed internal seals/flow design.

If they did...did the aftermarket cheap ones fix them also? I think for the extra $20, Id get an OEM part.

[AquilaBMW]

How do I get a hold of Max to get a couple of these tensioners? Do we get a BFC deal ?

[Cangelo629]

Timm is right on with his explanation and if you look on the part change number it is for that very reason yet BMW will not tell you that is why it was changed. The changed actually came from a outside supplier to BMW who re-engineered the part. More oil and better lubercation will help protect the plastic guides. It will also slow down the accelerated plastic degration with the continous injection of oil one of the main components on manufacturin of the guides is oil.


The chain tensioner is hydraulic - the spring allows the tensioner piston to extend and take up more oil. It is the hydraulic action of the tensioner that is important - the spring (even when new) is too weedy to do much work. And that is where the problems come from, the piston either sticks in the cylinder (as one of mine did) or the parts wear so that there is little or no hydraulic action.

Once the hydraulic action is compromised the chain will slap the guides until they disintegrate. Also, where there is wear, the oil leaks from the tensioner when the engine is switched off - and when you start it up again the chain will rattle around the guides, and that does them no good at all. How many times have we heard a member say that the car was fine when it was parked up, but the next time it was started it sounded like a bag of nails. That is due to wear, the oil was lost, the chain thrashed around on startup, and that was the end of the guides.

Although the guides will wear and fail eventually, if you don't change the tensioner when you get start-up rattle, they won't wear out, they will be flailed to death!

[CharlesAFerg]

I replaced mine, and my guides still failed 1 year later.

[Raudi Driver]

I'm going to do this also.

Does anyone know the difference between the Febi Bilstein and the OEM BMW Brand. I'm leaning towards the Genuine BMW as it's also cheaper but I'm wondering if the Febi has the better or longer spring.

[AquilaBMW]

I'm going to do this also.

Does anyone know the difference between the Febi Bilstein and the OEM BMW Brand. I'm leaning towards the Genuine BMW as it's also cheaper but I'm wondering if the Febi has the better or longer spring.

My understanding is the Genuine BMW OEM is the better or longer one.

- - - Updated - - -


I replaced mine, and my guides still failed 1 year later.

Were the guides already too far gone by the time you replaced the tensioner?

[andsteve]

Were the guides already too far gone by the time you replaced the tensioner?

I replaced my tensioner with the Febi unit and my center guide (U-shaped) failed a year later. No connection in my opinion

[ebida3]

Timm is right on with his explanation and if you look on the part change number it is for that very reason yet BMW will not tell you that is why it was changed. The changed actually came from a outside supplier to BMW who re-engineered the part. More oil and better lubercation will help protect the plastic guides. It will also slow down the accelerated plastic degration with the continous injection of oil one of the main components on manufacturin of the guides is oil.

So the question is when did they re-engineer the tensioners? How does one know if the aftermarket companies followed suit and re-engineered them also?

[robo740il]

Febi does have the longer spring

[IcemanBHE]

Almost like an echo in here.

:shifty

[Sobek]

I believe No. You might reduce the slack and therefore noise, but the fact is the plastic on the guides are worn and will continue to wear.
http://i62.photobucket.com/albums/h93/16valvedcaddy/007_zps9c8b5edc.jpg (http://s62.photobucket.com/user/16valvedcaddy/media/007_zps9c8b5edc.jpg.html)
This is the bottom of the U-guide, its suppose to be one level.

This still does my head in. What was the goal in going with fragile plastic guides instead of a second sprocket. Was it purely to save weight or reduce noise? Hardly seems worth it in the long run.

[AquilaBMW]

Okay guys.... I need your help here. I am getting conflicting information about these tensioners. I want to replace the ones in the cars and I am being told that only the OEM was updated. Supposedly, it is the one with the longer spring and is the better one.

I am also being told from various sources that the FEBI one was also updated and just as good. Can anyone confirm for certain if there is a difference between the FEBI and the OEM one? :dunno

[psjr]

This still does my head in. What was the goal in going with fragile plastic guides instead of a second sprocket. Was it purely to save weight or reduce noise? Hardly seems worth it in the long run.

BMW doesn't need to worry about the "long run," only the "warranty period."

[IcemanBHE]

I KNOW the OEM one is updated. I already said that. I have one laying right here.

But you want to make sure you get a NEW one. Not one laying on a shelf at the dealer. Have them ORDER one.

[machinemanjr]

Once the hydraulic action is compromised the chain will slap the guides until they disintegrate. Also, where there is wear, the oil leaks from the tensioner when the engine is switched off - and when you start it up again the chain will rattle around the guides, and that does them no good at all. How many times have we heard a member say that the car was fine when it was parked up, but the next time it was started it sounded like a bag of nails. That is due to wear, the oil was lost, the chain thrashed around on startup, and that was the end of the guides.



Timm, I replaced my timing chain tensioner in the last 5 k miles. I still occasionally have a slight rattle upon hot startup. How does one prevent the hydraulic action of the tenioner being lost when the car is not running? Once the oil pressure takes over the tensioning action from the internal spring, all is fine.


OP, I ordered my tensioner from max at oembimmerparts. It was made by FEBI. I see the ones max is selling now are INA OEM. http://www.oembimmerparts.com/BMW_Timing_Chain_Tensioner_W_Seal_By_Febi_p/11317531813e38.htm I wonder how widespread parts swapping is by these companies, that is, I wonder if BMW packages FEBI products and sells them for a 10% premium over the same part in a FEBI box. Hmmm. Logic says it probably happens..

[psjr]

Timm, I replaced my timing chain tensioner in the last 5 k miles. I still occasionally have a slight rattle upon hot startup. How does one prevent the hydraulic action of the tenioner being lost when the car is not running? Once the oil pressure takes over the tensioning action from the internal spring, all is fine.


OP, I ordered my tensioner from max at oembimmerparts. It was made by FEBI. I see the ones max is selling now are INA OEM. http://www.oembimmerparts.com/BMW_Timing_Chain_Tensioner_W_Seal_By_Febi_p/11317531813e38.htm I wonder how widespread parts swapping is by these companies, that is, I wonder if BMW packages FEBI products and sells them for a 10% premium over the same part in a FEBI box. Hmmm. Logic says it probably happens..

Yes, when Max says "OEM" after the manufacturer like "INA OEM" it means it's actually the same part you will get from BMW.

[machinemanjr]

Yes, when Max says "OEM" after the manufacturer like "INA OEM" it means it's actually the same part you will get from BMW.

So, they are the same part one would get from BMW just in a different box. Good to know, I guess there's not much reason to buy a BMW branded one then.

Thanks psjr.

[M I C H A E L]

I need to replace mine too. soon.

[AquilaBMW]

I replaced my Tensioner today, but I forgot to check was brand it was. I had it ordered through the dealer. Cooper was kind enough to inform me about the washer that goes with it - apparently this is an often forgotten piece when the tensioner is changed. It looking just like the one that I pulled, not sure if my car came with the upgraded one. Car was still warm when I replaced it, I will know tomorrow or in the next coming days if this will eliminate the occasional rattle on cold start up.

[IcemanBHE]

That is the best bet...and Ive no idea why it doesnt come with that "gasket".

[COOPERDB]

That is the best bet...and Ive no idea why it doesnt come with that "gasket".


That was my question as to why it does not come with the crush ring / "gasket ---

The answer - That's just the way the Germans do it ---

[AquilaBMW]

Well.... today cold start, no noise, no rattle. Car started up nice - it might be mental, but I could swear it sounded and felt smoother on start up. I know there was no chain slap and rattle, but I can swear that it feels smoother with the new tensioner, even when there was no slap / rattle / bang! It's day one, so we'll see how it goes.

[Raudi Driver]

Michael, I did mine today also and it's dead quiet. The motor was pretty quiet before with no rattle at startup but now the motor is even quieter.

I compared both the old spring and the new one (Swag from Germany).

Old Spring: shorter free length, higher spring rate

New Spring: Longer free length, lower spring rate.

I think that new tension piston could very well be easier on the chain guides as it might not press against chain as hard as the old style. Tim mentioned that the spring is only there to keep the piston open so oil can enter and do it's hydraulic work. Sounds like BMW made the spring softer to facilitate the hydraulic action.

I''ll bet that the higher rate spring didn't allow the piston to back off the chain enough and the system wasn't 100% hydraulic. Maybe now it is. Just thinking out loud.