Belts / Tensioner s/ Idler Pulley Replacement

Originally Posted by bmw_jeff_325i

I ran into a bit of trouble utilizing the T-60 socket to release tension on the lower AC belt tensioner

First, thanks for taking the time and energy to give back to the forum with your summary DIY writeup. That's they "payback" for the help; the advantage is we all learn from the effort.

As for the T-60, that's new to me because my INA mechanical tensioners (both old and new) for the 2002 5259, never need a Torx anything; they just take metric sockets to remove and replace.

So it's good to know the "newer" mechanical tensioners need the T60 socket which is not needed for the older mechanical tensioners.

Originally Posted by bmw_jeff_325i

I was affraid I was going to break a clip or puncture the hose.

It takes a lot of force ... and, in my case, I broke my angel eye bulb socket!

Originally Posted by bmw_jeff_325i

I dont see any like this in anyone's post

While the overall size and particulars of your mechanical INA tensioner is similar to mine, the T60 Torx bolt is wholly different. Yours is the first picture I've seen of that T60 Torx bolt (although I'm no expert - I only know what I have to fix).

Originally Posted by bmw_jeff_325i

I did remove the upper radiator hose utilizing the patented Bluebee screwdriver method

Aww. You just referenced that thread to make me feel good (since my motto is to always add value, I'm happy you received value from the method I proposed).

Originally Posted by bmw_jeff_325i

I found removing this hose essential in completing this DIY. It gives you clear sight and access of the idler pulley and upper accessory tensioner. I did NOT remove the air box.

Verrrrry interesting. Good information! Since it's easier to remove the hose than the air box, maybe you've hit upon a BETTER way to access the tensioners & belts!

The Bentleys did a lousy job of confusingly explaining how to remove that airbox and hoses anyway!

Originally Posted by bmw_jeff_325i

I utilized the hammer method ... No holding tool required.

Most experienced people seem to do it that way!

Me, I do it the inexperienced way ... plus I like the shiny new tools!

Originally Posted by bmw_jeff_325i

The nut loosened fairly easily

After I calmed down and watered my plants, the nut loosened fairly easily for me too (using just my arms as force with the holding tool in place). I think it's normal for it to be either easy or difficult. You just don't know ahead of time which it will be. I used the cn90 trick, except with rawhide as the 'string', and greased the shaft with anti-seize paste for the future.

Originally Posted by bmw_jeff_325i

This took about 3 trys to make it happen and I was concerned about stripping. My fall back plan was the patented CN90 method.

The first time I tried it, I stripped the threads, and the fan went on crooked. That single mistake cost me having to do the entire job twice!




Having been burned once, I'm (now) a firm believer in the "patented cn90 method"; but I'm glad the hand-held method worked for you!

Originally Posted by bmw_jeff_325i

The lower bolt on the tensioner was easier ... to loosen ... from below the car.

Yup. Especially if you don't remove the radiator fan shroud and the upper hose (which is how I initially did this job), you're like a kid jockeying for position in a snowball fight ... you find yourself jockeying from below to above, to figure out the best way to get your armaments in there given the angles they're hidden away.

Originally Posted by bmw_jeff_325i

I found the removal of the fan essential in removing the idler pulley bolt because it is so long it extends into the fan housing.

Good re-affirmation (so we can be more confident when telling others). Those who say you can do it w/o removing the fan must have a lot bigger tool set than I have.

Originally Posted by bmw_jeff_325i

I did see that apparently my belts were changed in 2007.

From the date code on the belts?

Originally Posted by bmw_jeff_325i

The most challenging part is releasing tension from the tensioners.

This is where I screwed up. While removing, one of the tensioners you pin, the other you don't (so you can access the holding bolts). It's the same as the new boxed tensioners; one is pinned, the other is not. However, once the belt is off, you have to unpin both old tensioners because you don't want to leave them with tension on to hurt someone who collects your trash.

I forgot that unpin step, and had to temporarily replace the tensioner to unpin it.

Originally Posted by bmw_jeff_325i

I found that you need to leave the pin in

Yes. This is often missed in many DIYs as they must just assume this stuff. However, even though I did it wrong myself, the first time, I was pretty sure I wrote it up that you needed to leave the pin in on one of the tensioners as you were installing it, until the belt was on.

Originally Posted by bmw_jeff_325i

I checked and re-checked the belts positions like 5 times.

In some of the DIYs, I was concerned that the belts had one fewer rib than the pulleys; so I was very careful to note (and photograph) the fitting on each of the pulleys. Turned out mine fit perfectly, and, while I checked them and re-checked them also, I also was relieved that it all fit quite nicely. My belts exactly fit their pulleys, IIRC.

Originally Posted by bmw_jeff_325i

Is the short spread on my upper mechanical tenisoner holes due to new belts?

IIRC, like you, I was surprised at how little the new mechanical tensioners needed to snap back to engage the new belts. In fact, since I had to remove the new belts a few times, I was doubly surprised at how LITTLE I had to move the new mechanical tensioners just to get the new belts off again.

Others can say more about the short spread concept than I though.

Originally Posted by bmw_jeff_325i

"cold start" squeeling sound is gone but I now have a constant moderate clicking sound in the vicinity of the alternator.

Congratulations on resolving the cold-start squealing!

IIRC, in my alternator thread, I spun the new and old alternator, and one of them had a barely audible but gently feelable (I'm making up the word feelable) clicking. I'd have to go back to the old thread to see which alternator it was. Is yours a Bosch 120?

Originally Posted by bmw_jeff_325i

Im going to try to post a video shortly.

Nice. It just purrs in that video! Nice contrast with the horrid screeching sound!

Originally Posted by bluebee

As for the T-60, that's new to me because my INA mechanical tensioners (both old and new) for the 2002 5259, never need a Torx anything; they just take metric sockets to remove and replace.

So it's good to know the "newer" mechanical tensioners need the T60 socket which is not needed for the older mechanical tensioners.

While the overall size and particulars of your mechanical INA tensioner is similar to mine, the T60 Torx bolt is wholly different. Yours is the first picture I've seen of that T60 Torx bolt.....

See attached picture of the lower AC Belt Tensioners for my 2003 525i (Build date 5/2003). Its also important to note that I was able to confirm that I had a lower mechanical tensioner by using a mechanics mirror to identify the T60 connection prior to starting this DIY. I had the new one in my hand to identify this as I looked but now everyone else has the photo. Hope this helps.

From the date code on the belts?

Yes...a date on the belt...that belts were slightly different in that they had an actual BMW logo on them...I assume this just means the service was done at the dealer as the CONTI part numbers were also clearly legible and were the same as the new ones I was putting on.

IIRC, like you, I was surprised at how little the new mechanical tensioners needed to snap back to engage the new belts. In fact, since I had to remove the new belts a few times, I was doubly surprised at how FAR I had to move the new mechanical tensioners just to get the new belts off again.

Others can say more about the short spread concept than I though.

At least I know now that I am not the only one. That helps in itself.

IIRC, in my alternator thread, I spun the new and old alternator, and one of them had a barely audible but gently feelable (I'm making up the word feelable) clicking. I'd have to go back to the old thread to see which alternator it was. Is yours a Bosch 120?

Not sure. Will have to check.

Nice. It just purrs in that video! Nice contrast with the horrid screeching sound!

I think it sounds like there is something wrong to me. My problem is im not sure what it is SUPPOSED to sound like. I have only had the car for about 3.5 months

Originally Posted by bmw_jeff_325i

See attached picture of the lower AC Belt Tensioners for my 2003 525i

That is a wonderful picture! I posted it to the thread showing us how to tell if you have mechanical vs hydraulic tensioners.

Nobody (to my knowledge) has mentioned that type yet, so, since the identification is visual, the photograph helps greatly.

Thanks for contributing to our combined tribal knowledge!

Originally Posted by bmw_jeff_325i

Thanks for the acknowledgement on my contribution Bluebee....


Anyone else have any comments on the engine sound?....or do we all agree it is purring like Blue says...??

For the record (but not to supersede any much more comprehensive parts/tools lists compiled by others (i.e. bluebee)), the following are what I used to complete this DIY:

Parts:
1 11281735899 Accessory Belt Tensioner Assembly; Water Pump/Alternator; Mechanical Type
1 11281738605 Idler Pulley/Roller; Water Pump/Alternator; Offset Mounting
1 11287512758 Accessory Belt Tensioner Assembly; AC Compressor Belt
1 4PK0865 Serpentine Belt/Ribbed Drive Belt; AC Compressor
1 6PK1538 Serpentine Belt/Ribbed Drive Belt; Alternator/Power Steering/Water Pump

Tools / Equipment:
Ramps
Wheel chocks
Hammer
32mm combination wrench
Large adjustable crescent wrench
Socket set (16mm & 13mm sockets)
T60 torx socket
Torque wrench
Screwdrivers

Other:
BMW OEM coolant
Distilled water

Originally Posted by bmw_jeff_325i

Thanks for the acknowledgement on my contribution Bluebee....


Anyone else have any comments on the engine sound?....or do we all agree it is purring like Blue says...??

I had to resurrect this video....it is still happening and drives me crazy each day.......its the clicking sound....which i am confident is coming from either the alternator or the idler pulley that I replaced....

Originally Posted by bmw_jeff_325i

Its really the pulsing "spinning" sound lack of a better way of describing it.

Can you get more footage over the alternator or a couple of photos.

This sounds like alternator noise. For some reasons, the M54 alternators tend to fail too early like 80K or so.

Only 3 items make that cyclical noise (rao rao rao ..... as in the video):
1. AC Compressor...I doubt it.
2. PS Pump (diff noise)
3. Alternator --> I think this is the culprit. The later Bosch alternator probably uses Chinese bearings (from what I gather from other forums).

To isolate noise:
- Remove the long belt, but first the short AC belt needs to be removed first.
Then re-install the AC belt.
Now run the car, the alternator light will be ON the dash but don't worry, this is just a short run of 1 min.
If the noise goes away then the source if likely your alternator.

Another method: Get a mechanic stethoscope and listen to the alternator itself.
A long screwdriver instead of the mechanic stethoscope is OK as well.

I should be quiet 'cuz I am guilty of leading the OP astray originally ... but I did feel a soft "clicking" in my hand when I spun my old alternator by hand (although I did not hear that when the engine was running).

Here's what I said above:
"IIRC, in my alternator thread, I spun the new and old alternator, and one of them had a barely audible but gently feelable (I'm making up the word feelable) clicking. I'd have to go back to the old thread to see which alternator it was. Is yours a Bosch 120?"

So, I would cautiously back up cn90 on the alternator premise.

I wonder why it started....because I'm sure it wasn't there before.....I remember only hearing the "cold start sqweel"....which of course is now gone.....maybe the source is the new belts which certainly have more tension than the older belts as evident by the location of the upper mechanical tensioner "holding holes" as Bluebee and I have reported previously....... I don't mean the belts themselves making the sound but rather the increased pressure on the 7.5 year old alternator pulley?.......anyway....I have no electrical issues with the car....so i guess I live with it.

Originally Posted by bluebee

Here's what I said above:
"IIRC, in my alternator thread, I spun the new and old alternator, and one of them had a barely audible but gently feelable (I'm making up the word feelable) clicking. I'd have to go back to the old thread to see which alternator it was. Is yours a Bosch 120?".

Sorry I missed this Blue.....my alternate appears be by "Valeo"....made in france....it is has the BMW insignia also....

Originally Posted by bmw_jeff_325i

Im at only 46k miles....Im going to wait til 60K.

Hi All,

WRT the above subject, I must say that all the help here has been exceptional and what I am about to say must not be received in a way that may remotely undermine any poster on this forum.

I have a 2001, E46,auto.(the E39 belt replacement is 90% similar in my view).

I replaced top plastic pulley and belt without removing fan, fan shroud or any related components as follows:

Tools:
1. 16mm tube socket on Tee bar(to cope with small offset needed with upper radiator hose, for upper tensioner). do not use an extension.
2. J-bolt (about 300mm long as used on most Jap car battery compartments.
3. masking(adhesive panelbeaters tape).
4. torx bit/screwdriver T20

What I did:

1.take off skid plate underneath.
2.remove AC belt by detensioning in clockwise direction(one handed operation)
3. remove airbox at front and on MAF side.
4. loosen and take off T20 srew on right side of radiatior/AC fan assembly.
5. remove packaging from new 6PK1538 replacement belt and place over 3 fan blades. Bulk of belt length must lie in front of fan, between radiator.
6. rotate visco fan blade and move belt over, bit by bit over each blade to get belt onto fan pulley side.
7. Using Tee bar and socket, open tensioner fully by turning full clockwise(almost to left fender). Using pre bent J-bolt(bend the threaded side to make another "j". this is now your own "s-bolt"). hook one end onto Tee bar and the other onto the first hole in the left fender.
6.with tensioner open, get under again.
7.using 100mm of masking tape, divide left and right side of serpentine belt 60/40 respectively and tape together to make an "8" shape. place over tensioner and fixed pulleys in "S" formation. work outward and then make sure belt is securely on alternator, power steer pump and main pulley(this forms a very apparent "L shape".
8.recheck the top side from fan to tensioner to alternator, going down.
9.replace AC belt
10.retension both belts, replace radiator corner screw, and start up.
10.switch off, recheck tensions and belt alignment, else you may endup with a 5PK instead of 6PK belt.
11. replace skid plate.

note. if your car has overheated(can be checked from drop in coolant top up bottle), bleed the system the usual way from nipple at the top of the radiator. the alternative is to crank up the heating and drive easy as the heat guage drops.

Now guys, bear in mind that I am an amateur in the true sense of the word and the purpose of the exercise was to get my car sorted and certainly not to find another way of doing things, so in good steed, all tweeks or criticism is accepted(upfront) !!

once again, thanks for a great site.

ps. where do I find the coolant overhaul info as mentioned here? this Beemer has 120+ miles already.

Good day from beautiful, sunny South Africa.

Originally Posted by kay1

where do I find the coolant overhaul info as mentioned here?

Thanks for taking the time to add value to the E39 tribal knowledge with your information about removal of the belt-drive system components.

As for the cooling system overhaul threads, there are tons in the VERY best of E39 Links. Here are just a few ...

Cooling system overhaul DIYs:
- Pictorial look at typical E39 cooling system failure modes (1) (2) (3)
- Complete cooling system overhaul recommended parts list (1)
- Coolant, for engine, automatic transmission, power steering, and AC evaporator cooling (1)
- Bleeding the cooling system (1) (2) (3)
- How to refill M52/M54 coolant DIY by cn90 (1)
- Cooling system DIY (cn90 1997-1998 M54TU) (cn90 V8) (aioros '99-03 M54) (Ågent99 '01 530i) (pelican 3-series)
- E39 Fan shroud removal DIY (Besian) (M54)
- Removal instructions for the alternator & drive belt system of a 2002 525i
- Removal instructions for the fan shroud of a 2002 525i
- Tools necessary for a cooling system overhaul
- Cooling system overhaul tips (fan clutch nut removal tools) (cn90 fan clutch nut replacement trick) (bb hose removal trick) (o-ring replacement parts)
- Cooling system overhaul mishaps (broken radiator nipple) (crooked fan clutch nut) (broken bleeder screw) (thermostat loom misplaced) (broken expansion tank nipple & cn90 repair) (expansion tank fell apart inside)
- Expansion tank floating mechanical coolant level sensor height (1) (2)
- High instrument cluster check of the cooling system temperature KTMP (1)
- Cooling system date stickers & radiator date codes & markings (1) (2)
- What brand of waterpump to buy (1)
- Fan clutch failure modes (1)
- Fixing a head gasket coolant leak (1) (2)
- What is the temperature of the coolant & when the thermostat opens under normal conditions (1)
- Modifying the cooling system (pressure cap) (zero psi fluids) - Zionsville (BlackBMWs) (William) (ohmess)
- Understanding the AUC automatic air recirculation (aka stink) sensor (1)
- Behr radiator and Behr expansion (aka surge) tank autopsy (1) (2) & request for another autopsy (1)
- Debugging overheating problems not related to low fluid levels (1)
- How to install and remove an Oetiker clamp (1)
etc.

Originally Posted by bmw_jeff_325i

Just a follow up on this post for future use. This sound was definitely coming from the alternator as it was just replaced yesterday (finally) and the "click" is now gone. I can only deduce that when I replaced the belts and tensioners they added increased force to the older alternator pulley contributing to the "click" and probably an expedited failure of the alternator.
Again to recap:
1 - I had the infamous cold start sound (no "click").
2 - I replaced the belts, tensioners and idler pulley.
3 - "Click" develops.
4 - Approx. 2.5 months later my battery light comes on. Alternator is gone.
5 - Alternator replaced. Click gone.

I replaced both the AC and alternator belts today. Here are a couple of things I came across.

I removed the air box, fan shroud and fan for better access. I had bought the two fan wrenches off eBay and they worked well - once you find the two nuts on the water pump pulley that will fit into the slots on the wrench.

Both my tensioners are mechanical (build date 11/02). The AC belt tensioner had a torx hole only - no built in hex head. I didn't have the correct size torx so I lent on the tensioner from above with the heel of my hand and got the belt on - I'm a big guy!! The alternator tensioner had the hex head and it was a big help.

Removing the air box was key in getting the fan back on. I tried from below, but there just wasn't enough room to support the fan while trying to thread it onto the water pump.

I had a little difficulty getting the expansion tank back in place and lost some coolant through the tube that goes into the top of the expansion tank. In hindsight, I needed to plug the hole when I first removed it.

As usual, I took my time as this was the first time attempting this repair. I spent the better part of six-hours, although an hour of that was spent cleaning the greasy dirt that was impacted on the viscous fan. Next time, I'll have it done in a few hours. My last car (Hyundai) took 30-minutes!!

Thanks to everyone who contributed to this thread.

Originally Posted by dcotti

The AC belt tensioner had a torx hole only - no built in hex head.

We've seen this before (only on a 2003) as shown in this thread:
- How to tell if you have spring-drive or hydraulic belt tensioners or both (1)

Originally Posted by dcotti

Removing the air box was key in getting the fan back on.

Also key is the cn90 trick to get the fan on straight:
- How to get the fan clutch nut on straight



Having done this job myself, I wouldn't even "think" of doing this job without removing at least the upper radiator hose, and the airbox and the fan clutch - but maybe not the radiator (depends on my mood).

Originally Posted by dcotti

In hindsight, I needed to plug the hole when I first removed it.

Interesting. I plugged mine with a stick found on the ground.


In hindsight, I'd remove the nipple intact, out of the radiator.
- Removing the radiator nipple intact


As for the fan clutch counterhold tool, I also highly recommend it:

Appears you can replace only the pulley separately on both the mechanical AC assembly and mechanical tensioner assembly, both use the same pulley. Before finding this out had replaced my entire tensioner assembly with an Ina brand and plan on doing the AC assembly later in the spring. Came across a E46 DIY where they only replaced the mechanical pulley's as the assembly was still in great shape. http://forum.e46fanatics.com/showthread.php?t=735884

Gates part #38018 brand at Napa in Canada $21.09 each heard good things about Gates belts, etc so will buy this one local.
GoodYear #49024 pulley $15.35 at partsource.ca http://74.208.162.181/part-source.ca...ulleys&mode=PA
Dayco #89133 Bumper To Bumper Canada $30.71 - at Autozone as Duralast #231133, both manufactured by Ina

Note the mechanical pulley is different from the hydrolic pulley.

Originally Posted by fiat84

Appears you can replace only the pulley separately on both the mechanical AC assembly and mechanical tensioner assembly

This is interesting. Please keep us informed! Especially about what parts fit best.

The guys over on the E46 side doubted you could replace just the mechanical tensioner ... but I found two instances for the E46 showing that you could replace JUST the pulley from the mechanical tensioner.

At least it says so (by two users) in this E46 reference:
- a/c belt tensioner pulley

And, it says so by one user in this E39 reference:
- Squeak

I will also add your information to the mechanical vs hydraulic tensioner discussion:
- What is the difference between mechanical and hydraulic tensioners

Originally Posted by fiat84

Note the mechanical pulley is different from the hydrolic pulley.

That might explain this BMW SIB:
- WHY would a hydraulic belt tensioner be any quieter than a mechanical belt tensioner?

Originally Posted by fiat84

Appears you can replace only the pulley separately on both the mechanical AC assembly and mechanical tensioner assembly, both use the same pulley. Before finding this out had replaced my entire tensioner assembly with an Ina brand and plan on doing the AC assembly later in the spring. Came across a E46 DIY where they only replaced the mechanical pulley's as the assembly was still in great shape. http://forum.e46fanatics.com/showthread.php?t=735884

Gates part #38018 brand at Napa in Canada $21.09 each heard good things about Gates belts, etc so will buy this one local.
GoodYear #49024 pulley $15.35 at partsource.ca http://74.208.162.181/part-source.ca...ulleys&mode=PA
Dayco #89133 Bumper To Bumper Canada $30.71 - at Autozone as Duralast #231133, both manufactured by Ina

Note the mechanical pulley is different from the hydrolic pulley.

UPDATE: Only use the Dayco #89133 made by Ina. Reason: Changed the AC pulley only with a Gates #38018 and a few weeks later it made an intermittent rattling grinding(unlubricated metal on metal) sound. It only made the loud noise when the engine got really hot after about 30+ minutes driving and made no noise before that. The Gates pulley looked slightly slimmer so it DOES NOT appear to match factory specs and did not spin by hand as smoothly as the better built factory pulley. Put the old factory pulley back on which is still in great condition and no more rattling. Had recently changed the AC belt a two months before this AC pulley only change.

The original post link on the E46 M54 engine thread all used the Dayco #89133 pulley made by Ina and all report 100% success. Do not take a chance like I did using a supposedly equivalent different brand of pulley as they are different than the factory original spec.

Cannot seem to figure out how to EDIT my previous post to add this important update.

Thanks for the update. We appreciate the efforts of people who advance our knowledge with reports of first-hand experience.

Originally Posted by fiat84

Cannot seem to figure out how to EDIT my previous post to add this important update.

I didn't check the dates of your post but I get two months before the edit button disappears.

In fact, I use that extensively to improve my posts, after the fact, especially in the bestlinks, so that I can make hundreds of improvements during that time without having to burden everyone with it popping up as a new post. It's a nice feature.

UPDATE: Changed the AC pulley only with a Gates #38018 and a few weeks later it made an intermittent rattling grinding sound. Got loud when the engine ran for awhile so it DOES NOT appear to match factory specs. Put the old factory pulley back on which is still in great condition and no more rattling. Maybe try the Dayco #89133 since it is made by Ina. Had recently changed the AC belt a month before.

I added this to the canonical thread on tensioner & pulley selection so that others benefit from your experience:
- Do we have hydraulic or mechanical serpentine polyribbed drive belt tensioners?

Sorry to revive this thread, but does anyone know how the washer for the tensioner pulley mounts back with the pulley and the bolt? I have a Dayco pulley, a T50 torx bolt and a washer. In which order (alignment) do they go back on the engine?
For example if I go bolt, washer, pulley, mounting surface, the rolling pulley hits against the mounting surface. Bolt, pulley, washer, mounting surface doesn't seem to work either (pulley slips right off).
I feel so dumb.

For the cross-linked record, this thread today has a suggestion for the Dayco replacement pulley sourcing:
-> E39 (1997 - 2003) > 2003 530i - A/C Tensioner Pulley part number help

Originally Posted by dvsgene

You can also buy a Dayco 89133 pulley from your local auto parts store. In many cases, it's just a INA roller in the box (same as OEM)

You can doublecheck application here:

http://www.accessdayco.com/Auto.aspx

If your local auto parts store doesn't stock it, you can buy it from Amazon:

http://www.amazon.com/Dayco-89133-Id.../dp/B001C6ITTK