Belt tensioner help

[80stech]

They look a lot different but like was said earlier the mechanical one has the hex for releasing the tension.

[Overboost]

Would it be easy to see by simply looking down into the engine bay?

[80stech]

Should be pretty easy, especially if you see the hex lug. If you have the hydraulic set up then a replacement pulley is available. If you have the mechanical then you need to replace the assembly. Both systems are interchangeable though. The hydraulic is supposed to be the updated system but I have an improved mechanical one (Delco pro) ready to replace my hydraulic one when it fails. I have a theory that the hydraulic one is transmitting more vibration at times.

[Overboost]

Originally Posted by 80stech

Should be pretty easy, especially if you see the hex lug. If you have the hydraulic set up then a replacement pulley is available. If you have the mechanical then you need to replace the assembly. Both systems are interchangeable though. The hydraulic is supposed to be the updated system but I have an improved mechanical one (Delco pro) ready to replace my hydraulic one when it fails. I have a theory that the hydraulic one is transmitting more vibration at times.

I took the intake snorkel (upper shroud) off and still for the life of me can't see which tensioner it has. I would have really needed to take the fan and fan shroud off to get a clear view of the tensioner so I just ordered the mechanical tensioner kit with all drive and A/C belts and idler pulley AND the hydraulic tensioner itself. I am trying to avoid taking this apart twice so I will have everything I need once it all arrives and then take it apart and use the correct tensioner. FCP is a pretty good company so I hope to send back the unused tensioner I didn't need.

[tttomttt]

I just thoughtfully went through this on my recently purchased 05 530I when I heard a belt squeak yesterday as I was running errands. When I popped the hood I saw the old type tensioner still installed. I went through all the realoem part numbers and decided to replace the mechanical tensioner with another mechanical tensioner rather than "upgrade" to the hydraulic type. My reasoning is in order to release the tension to remove the belt with the hydraulic type you have to pop the dust cap off and use the torx bolt for the pully to release the tension from the hydraulic cylinder and it becomes a little tricky if you are not careful. However as pointed out already with the mechanical tensioner you have the 16mm hex (5/8 sae) right in front to release the tension. Granted in the future with the hydraulic tensioner you will be able to just replace the pully with a new one sold separately and not need to replace the whole assy. FCP Euro will guarantee the tensioner for life.
Tom

[80stech]

I agree Tom, using the torx head on the tensioner bolt to release tension is not so great. It can also lead to someone using a pry bar against the belt which is not good either! I also have a bit of a problem with getting some belt vibration at certain times with the hydraulic tensioner. I possibly might have created some of my own problem by switching to the aftermarket market URO aluminium fan pulley which is not as concentric as I would like. As a bit of an experiment I just put on the premium conti belt with the variable length ribs. Problem seems to have disappeared but I think more "masked" than "solved." I do like your philosophy on using the mechanical from FCP uro but I would keep a spare in the back(or maybe the old one if it is still good) The mechanical one should be a lot easier to change on the road as well. If you have a spare mechanical one you might be able just to switch out the pulley assembly as well.

[upallnight]

The hydraulic tensioner does not use all of the same mounting holes as the mechanical tensioner. You may want to chase out the bolts holes not used by the hydraulic tension if you decide to upgrade to a hydraulic tensioner. Also, I believe the length of the belt is different for the two tensions, so you will have to upgrade the belt as well.

[Overboost]

Originally Posted by upallnight

The hydraulic tensioner does not use all of the same mounting holes as the mechanical tensioner. You may want to chase out the bolts holes not used by the hydraulic tension if you decide to upgrade to a hydraulic tensioner. Also, I believe the length of the belt is different for the two tensions, so you will have to upgrade the belt as well.

I checked the 2 kits from FCP (mechanical vs. hydraulic) and they listed the same belt so hoping that will not be an issue. Once I get it apart next week I will know what I actually have and make the decision. I will probably put it back the way it was, it lasted 163,000 miles this way.

I have scheduled next week for annual maintenance for the girl. Along with the drive belt, idler and tensioner, the AC belt and tensioner, I also will replace the water pump while everything is off and do a minor power steering overhaul (reservoir and reservoir hoses) along with the dreaded ball joints.

FCP Euro is my friend this week.

[Overboost]

All my shipments finally arrived. Turns out I did have the hydraulic tensioner once I got everything apart. Replaced the hydraulic drive belt tensioner and AC belt tensioner with pulleys, idler pulley, belts and water pump. The pump seemed solid but at 163,000 miles and since it was staring me in the face with just 4 nuts, I just replaced it while I was so far in there. Also replaced the power steering reservoir and both hoses to it. It had been slowly leaking on my alternator. It took the better part of the day taking my time, inspecting and cleaning parts but glad to put that all behind me. Nice and quiet again.

[80stech]

The power steering reservoir was probably just a loose clamp on the bottom hose, but money not wasted since now you have a new filter. Hopefully you got a good water pump that will last as long as the original.