Tensioner pulley

kkasson · 08-26-2015, 08:10 PM

Can you replace the tensioner pulley separately from the whole assembly?

I just replaced my belt/tensioner/idler. I replaced the whole assembly. I searched around and didn't find any info on replacing the tensioner pulley separately...on the E46 the tensioner pulley wasn't sold as a separate part from BMW, but it just bolted onto the tensioner and there were aftermarket parts available. Seems to be the same way on the E90.

When I took my old tensioner off, I popped off the pulley cover and was surprised to see that there was just a torx bolt holding the pulley on. It also seemed to be magnetic, so it should be okay to reuse the bolt with a new pulley.

Dayco lists 89133 as a tensioner pulley for the car. According to the specs on their site, outer diameter seems correct...but the width seems a little less than the original pulley.

So, just for the sake of my own curiosity, and maybe for anyone else searching for this, can just the tensioner pulley be replaced? Has anyone done it?

sankohuy · 08-26-2015, 10:29 PM

I'm about to do this myself. How easy was it for you? Did you had to jacked the car up? Did you removed the radiator fan?

kkasson · 08-26-2015, 11:32 PM

I have a 328i, so it's quite a bit easier than the 335. I didn't have to remove anything, I was able to get both the tensioner and idler off with both the fan and the intake hood in place.

For the 335, Bentley says you'll need to remove a hose from a clip on the bottom of the radiator. I'm not sure why, because it doesn't seem to be in the way of anything. It looks like you should be able to reach that from the top. You'll definitely need to remove some of the air ducts in front of the belt. It doesn't seem like you need to lift the car, but I'm not sure. There's a screw on the bottom of the fan that you might need to access from the bottom, but I was able to do mine with no problems without removing the fan. Not sure if you can do the same on yours. If you take the ducts off the top, you should be able to see pretty easily if there's enough room to get everything out.

EDIT: As an aside, I'm very happy with the design of the belt on this car. I thought the belts were easy to change on my E46, even though I had a stupid fan clutch to deal with there. This one can easily be done in 10 minutes or so.

AllBlackBimmer · 08-27-2015, 07:23 AM

http://www.ecstuning.com/BMW-E90-328...e/Drive_Belts/

http://www.ecstuning.com/BMW-E90-328...lts/ES2706891/

http://www.ecstuning.com/BMW-E90-328...Belts/ES21742/

Above are links to just the pully - the link is to the BMW branded one, but there are other's on ECS's site that are cheaper.

My understanding is you have to replace the torx bolt as it is a one-time use bolt... and its like $5 so why not buy a new one while your at it.

Im doing my belt, pulley, etc... here sometime in the near future and will probably just buy the complete service kit ECS offers.

kkasson · 08-27-2015, 09:08 AM

That's not just the pulley, it's the whole tensioner?

I'm talking about replacing just the pulley and leaving the tensioner spring part alone. The bolt that holds the tensioner to the engine is one time use and should be replaced if the tensioner is removed from the engine, but the bolt holding the pulley to the tensioner doesn't seem to be.

AllBlackBimmer · 08-27-2015, 09:34 AM

Quote:

Originally Posted by kkasson

That's not just the pulley, it's the whole tensioner?

I'm talking about replacing just the pulley and leaving the tensioner spring part alone. The bolt that holds the tensioner to the engine is one time use and should be replaced if the tensioner is removed from the engine, but the bolt holding the pulley to the tensioner doesn't seem to be.

Oh... I misunderstood... but for the price of the whole tensioner (non BMW brand) ... like $40-60... I'd just replace the whole thing and be done with it. Not sure you can buy just the pulley itself from anywhere?

kkasson · 08-27-2015, 09:50 AM

I tend to agree, which is why I went ahead and just replaced my whole tensioner. But according to some of the posters on here, the tensioner springs can last way longer. I believe there are some with 200k+ miles that are working fine.

You can get a Gates 38018 on RockAuto for $11. They also have a Continental pulley for $10. The whole tensioner is anywhere from $60 to $100.

I can't speak to the reliability of those vs the INA pulleys, but it might be helpful for someone out there.

08-26-2015, 08:10 PM	#1
kkasson Lieutenant 187 Rep 589 Posts Drives: 07 BMW 328i, 08 BMW 528i Join Date: Jun 2015 Location: CA iTrader: (0)	Tensioner pulley Can you replace the tensioner pulley separately from the whole assembly? I just replaced my belt/tensioner/idler. I replaced the whole assembly. I searched around and didn't find any info on replacing the tensioner pulley separately...on the E46 the tensioner pulley wasn't sold as a separate part from BMW, but it just bolted onto the tensioner and there were aftermarket parts available. Seems to be the same way on the E90. When I took my old tensioner off, I popped off the pulley cover and was surprised to see that there was just a torx bolt holding the pulley on. It also seemed to be magnetic, so it should be okay to reuse the bolt with a new pulley. Dayco lists 89133 as a tensioner pulley for the car. According to the specs on their site, outer diameter seems correct...but the width seems a little less than the original pulley. So, just for the sake of my own curiosity, and maybe for anyone else searching for this, can just the tensioner pulley be replaced? Has anyone done it?
	Appreciate 0 Tweet Quote

08-26-2015, 10:29 PM	#2
sankohuy First Lieutenant 44 Rep 385 Posts Drives: E92 335i Join Date: Oct 2012 Location: norcal iTrader: (0)	I'm about to do this myself. How easy was it for you? Did you had to jacked the car up? Did you removed the radiator fan?
	Appreciate 0 Quote

08-26-2015, 11:32 PM	#3
kkasson Lieutenant 187 Rep 589 Posts Drives: 07 BMW 328i, 08 BMW 528i Join Date: Jun 2015 Location: CA iTrader: (0)	I have a 328i, so it's quite a bit easier than the 335. I didn't have to remove anything, I was able to get both the tensioner and idler off with both the fan and the intake hood in place. For the 335, Bentley says you'll need to remove a hose from a clip on the bottom of the radiator. I'm not sure why, because it doesn't seem to be in the way of anything. It looks like you should be able to reach that from the top. You'll definitely need to remove some of the air ducts in front of the belt. It doesn't seem like you need to lift the car, but I'm not sure. There's a screw on the bottom of the fan that you might need to access from the bottom, but I was able to do mine with no problems without removing the fan. Not sure if you can do the same on yours. If you take the ducts off the top, you should be able to see pretty easily if there's enough room to get everything out. EDIT: As an aside, I'm very happy with the design of the belt on this car. I thought the belts were easy to change on my E46, even though I had a stupid fan clutch to deal with there. This one can easily be done in 10 minutes or so.
	Appreciate 0 Quote

08-27-2015, 07:23 AM	#4
AllBlackBimmer Colonel 815 Rep 2,869 Posts Drives: 2019 X3 m40i Join Date: Aug 2011 Location: USA iTrader: (-1)	http://www.ecstuning.com/BMW-E90-328...e/Drive_Belts/ http://www.ecstuning.com/BMW-E90-328...lts/ES2706891/ http://www.ecstuning.com/BMW-E90-328...Belts/ES21742/ Above are links to just the pully - the link is to the BMW branded one, but there are other's on ECS's site that are cheaper. My understanding is you have to replace the torx bolt as it is a one-time use bolt... and its like $5 so why not buy a new one while your at it. Im doing my belt, pulley, etc... here sometime in the near future and will probably just buy the complete service kit ECS offers. __________________ 2019 X3 m40i:Carbon Black:Executive:Premium:Adaptive:Vernasca:699M:HK: Ambient:IND trim:M Mirrors:15mm spacers:Maxton lip:20% tint windows/pano:dsg paddles:TLG mudflaps 2008 328i E90 Jet Black:6MT:RWD:Premium:Sport:Xenon:MTEC V3 AEs:Front Splitters:CF spoiler:19" VMR FF v710
	Appreciate 0 Quote

08-27-2015, 09:08 AM	#5
kkasson Lieutenant 187 Rep 589 Posts Drives: 07 BMW 328i, 08 BMW 528i Join Date: Jun 2015 Location: CA iTrader: (0)	That's not just the pulley, it's the whole tensioner? I'm talking about replacing just the pulley and leaving the tensioner spring part alone. The bolt that holds the tensioner to the engine is one time use and should be replaced if the tensioner is removed from the engine, but the bolt holding the pulley to the tensioner doesn't seem to be.
	Appreciate 0 Quote

08-27-2015, 09:50 AM	#7
kkasson Lieutenant 187 Rep 589 Posts Drives: 07 BMW 328i, 08 BMW 528i Join Date: Jun 2015 Location: CA iTrader: (0)	I tend to agree, which is why I went ahead and just replaced my whole tensioner. But according to some of the posters on here, the tensioner springs can last way longer. I believe there are some with 200k+ miles that are working fine. You can get a Gates 38018 on RockAuto for $11. They also have a Continental pulley for $10. The whole tensioner is anywhere from $60 to $100. I can't speak to the reliability of those vs the INA pulleys, but it might be helpful for someone out there.
	Appreciate 0 Quote