Serpentine belt emergency, stuck in Joseph OR

Thank you all for the extremely valuable hints! The daytime high temperature is forecast to remain below freezing (and overnight as low as 9 degrees F) so all these tips and suggestions are gold as far as my not freezing to death. Keep 'em coming!

.......
- Thread the new serpentine belt through the pulleys
- "Pull the pin" on the new tensioner assy
......
Forgot to ask. Do you have a rear AC unit on your van? Turns out there are two different tensioners. One with a torx socket and one without. The non rear AC unit tensioners have what looks like a 12 point bolt head for applying the tension release. In your picture it's above the AC compressor at about 11 o'clock. No idea what the size might be.....
 
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sprint2freedom

2008 NCV3 170ext
Negative on the rear AC.

So I biked 15 miles to the NAPA and picked up the 36mm wrench today, and bought a 12pt 17mm socket (I only had a 6pt in my kit) for holding/rotating the tensioner. I'm not 110% confident that's the correct size but testing with a 12pt 17mm combination wrench it seemed like a pretty solid fit.

Also bought a 27mm socket for the crankshaft, and a 4lb sledge hammer for hitting the 36mm wrench. Might not need the latter but it sure beats a repeat of that 15 mile ride in the snow if I find out I do...
 

sprint2freedom

2008 NCV3 170ext
I'm still waiting for parts to arrive but with the sun coming out today I decided to start the job and try to get the disassembly aspect out of the way.

Here's how it went and what I learned:

Engine fan - I first tried putting the wrench on the fan nut and whacking it clockwise but that just spun the crankshaft. After putting a 27mm socket and breaker bar on the crank, the crank stayed put but the fan belt slipped causing the fan nut to spin without loosening. What finally worked was flattening the old serpentine belt against itself and then routing it up over the top of the fan pulley. I hooked one end (a loop) around the body of the tensioner (not the tensioner pulley), and let the other end (a loop) hang down. Then I used a pair of long handled loppers I had on hand as a lever arm to apply downward leverage to the inside the loop, against the front subframe (as the fulcrum) and pulling the belt tightly downward. See drawing below. With that temporary setup in place, a solid whack against the 36mm wrench with a 3 lb hammer broke the fan nut loose immediately.

Fan shroud - After undoing the clips on each side, I initially tried maneuvering the shroud from side to side to skirt the radiator hose. That wasn't going too well, so I decided to follow the excellent suggestion of dropping the coolant reservoir as far down as it could go. I was then able to unhook the upper radiator hose on my right without losing a single drop of coolant just as advertised. With the hose undone the shroud and fan then lifted straight up and out. I would highly recommend this approach as it was much faster and easier than struggling with the shroud.

Idler - I managed to get the disintegrated idler out by removing the fan pulley bolts (10mm e-torx qty 4). Neither the pulley or stretch belt wanted to come off at first but after spinning the crankshaft clockwise a few revolutions the pulley loosened up a bit and could be wiggled and walked off. Both idlers then spun out using a T50 torx bit. The lower idler had a dust cap that had to be pried off with a flathead screwdriver.

Tensioner - After removing the single long bolt (14mm e-torx) in the center, I put the 17mm 12pt socket on the tensioner and turned it CCW. The tensioner spun a little bit and in the process it loosened up enough for me to pull it off.

I haven't removed the fan bearing support yet but that looks like just a few e-torx bolts. I'll follow up when the job is fully complete.

Many many thanks to everyone who shared their wisdom in this thread!

illustration.jpg
 
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sprint2freedom

2008 NCV3 170ext
Isn't that ridiculous that that wide head bolt just won't clear the fan pulley by a tiny bit. I'd be tempted to slice the head off, find a hex bolt with same threads and put the new idler on, perhaps stacking some washers if necessary. I have seen videos of an emergency serp belt change where they slip the belt around the outside of the fan blade cage after removing the connector and ground wire. That could get you on the road quickly. This seems to be an insane amount of work and a lot of expense and time getting the fan pulley off. BTW, my name is not Rube Goldberg. LOL Best of luck to you!
Totally ridiculous. But I guess it's not all bad, as it had the side effect of forcing me to finally do the rest of the belt-related PM..:idunno:

FWIW, wrapping the belt around the fan blade cage is good in theory but doesn't seem like it would work because the fan spins freely around the fan nut unless the viscous clutch is engaged.
 
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FWIW, wrapping the belt around the fan blade cage is good in theory but doesn't seem like it would work because the fan spins freely around the fan nut unless the viscous clutch is engaged.
Actually, the video I was watching was for replacement of the serp belt. The author squeezed the edges of the serp belt around the tiny space between the fan blade cage and the fan shroud (fed it through) This allowed him to install a serp belt without removing the fan and the stretch belt. He had to remove the vertical ground wire and disconnect the electrical connector going to the fan motor to get the belt beyond that point. I have not done this, but the video took us through the process and is completely believable.
 

sprint2freedom

2008 NCV3 170ext
Actually, the video I was watching was for replacement of the serp belt. The author squeezed the edges of the serp belt around the tiny space between the fan blade cage and the fan shroud (fed it through) This allowed him to install a serp belt without removing the fan and the stretch belt. He had to remove the vertical ground wire and disconnect the electrical connector going to the fan motor to get the belt beyond that point. I have not done this, but the video took us through the process and is completely believable.
Oh, I guess I misunderstood you- I thought you were talking about wrapping the belt around the fan cage to immobilize the fan in order to unscrew it..

Yes, slipping the belt through the gap is very doable and is exactly how I got the belt out myself, except that there were no wires to disconnect on my 2008. Belt replacement without changing pulleys or idlers seems feasible, although without removing the fan there is very little access to hold a wrench, ratchet, or even touch anything with a fingertip. With enough perseverance it seems possible but I hope I never have to do it.
 
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sprint2freedom

2008 NCV3 170ext
Got the van back up and running today, with a few caveats and comments:

- First problem: the viscous fan seems to run continuously now, with the coolant temperature at 45 degrees F. It's not quite as loud as I remember it being when idling on a hot summer day, so perhaps it's only partially "coupled" rather than full speed, but there's noticable airflow under the hood- I don't remember that happening previously but it's possible I'm mistaken. I did clean the fan with a wet paper towel and dish soap, and noticed peanut buttery dirt packed in around the sensing coil so I carefully cleaned that crap out with the pointy end of a zip tie. In general I was careful to store the fan in the upright position as suggested here, however I briefly (5-10 seconds) laid it down during the cleaning process. Did I ruin the fan? It looks like it's due for replacement anyway, so I probably made the wrong call and should have just ordered one as PM.

- The original belt is a Contitech Conti-V 7 PK 2035 (made in Germany). The new Contitech belt is a Contitech 7 PK 2035 (made in Italy). However, up close they look substantially different. The original is black rubber with seven very clear "V"-shaped notches in its cross section. The new belt is more of a felt-impregnated gray color and the seven ribs have a more vague "D" cross section. I ended up using the new belt, but I was surprised at how different they looked. I searched briefly, but couldn't find anything about what changed.

- The fan bearing bracket was slightly different in that it had fewer threads and a shoulder where the fan pulley mounts. It looks like the newer casting includes more metal in the corners as well, presumably for additional strength.

- There was a little weirdness in how the fan bearing bracket is built. There's a tiny 'daughter' bracket that screws into it, and then a big cast aluminum tube on the front of the engine screws into the daughter bracket. So you begin by removing the large diameter long screw through that cast aluminum part. The rest then comes out as a unit once you've undone the 4 smaller screws that hold the bracket. One of those screws is shorter than the other 3, so be sure to keep track of which is which.

- The fan belt was a nightmare to get back on. I tried to install the new stretch belt first but gave up on that after realizing how much shorter it was than my old belt. Even getting the old belt on didn't go smoothly. I burned through about 30 zip ties trying to walk it back onto the fan pulley but I must have been doing something wrong. I finally succeeded but the belt was offset about 3 grooves from where it needed to be and it took me a lot of failed attempts to figure out a way to move it over. What finally worked was twisting the belt 45 degrees and jamming it in the direction I wanted it to go just with my bare fingers on one hand while using the other hand to turn the crank with a 27mm socket.

- The serpentine belt was a piece of cake. It went on according to the diagram, starting with the inside-out horseshoe bend that hooks around the tensioner pulley. The hardest part was getting it over the final pulley (I put it on the A/C pulley last), but once I got the edge of it to hang on I spun the crank by hand a few times and it walked right into the grooves where it needed to be.

- I noticed the new idler pulleys are narrower than the original equipment. They seem to be exactly the width of the belt rather than a couple mm wider. Other than detail that the markings and construction seem overwhelmingly similar.
 

hilld

Active member
You should be ok on your viscous fan clutch. They don't totally disengage like an AC clutch for example, there was probably always airflow, it might just be more pronounced at 45*F. Feels a bit chilly. Nice job, now you can continue your trip or stay a few more days. Nice part of the state.
 

sprint2freedom

2008 NCV3 170ext
Thanks guys.

What would I recommend doing based on this experience? Carry a spare belt (~$30) and at least one spare idler pulley (~$20). Unfortunately due to the poor design where the upper idler can't be removed without removing the fan pulley even this advice may have been enough for me to complete the repair on a forest road, but it would have greatly shortened the waiting time for parts to arrive as I could have gotten the sockets, the 36mm wrench and hammer locally within the first 24 hours.

I did manage to repair my cracked shroud- once I got it out I could see that the crack was only on one half of the shroud. So I drilled probably 15 pairs of 1/8" holes on either side of the crack and then looped zip ties between them, snugging them up to close the gap. Obviously it's not perfect but it's a whole lot better than what it was before. The shroud looks and behaves like a single piece of plastic unless you look closely.

The total cost of this debacle worked out to $60 in tools, $275 in parts and $210 in lodging at an RV park. So $545, plus 7 days lost time. A big thanks to Steve at Europarts-SD and the Postal Service for getting the replacement parts to me in only 4 days time, and to NAPA for special ordering the 36mm wrench with it arriving in only 1 day(!).

It's a huge relief to have the belt back on.. especially when reading the forecast for tomorrow night:

"A 20 percent chance of snow showers before midnight. Partly cloudy, with a low around 6."
 

Dima74

Independent & Self Reliant - From Chattanooga TN
Thanks guys.

What would I recommend doing based on this experience? Carry a spare belt (~$30) and at least one spare idler pulley (~$20). Unfortunately due to the poor design where the upper idler can't be removed without removing the fan pulley even this advice may have been enough for me to complete the repair on a forest road, but it would have greatly shortened the waiting time for parts to arrive as I could have gotten the sockets, the 36mm wrench and hammer locally within the first 24 hours.

I did manage to repair my cracked shroud- once I got it out I could see that the crack was only on one half of the shroud. So I drilled probably 15 pairs of 1/8" holes on either side of the crack and then looped zip ties between them, snugging them up to close the gap. Obviously it's not perfect but it's a whole lot better than what it was before. The shroud looks and behaves like a single piece of plastic unless you look closely.

The total cost of this debacle worked out to $60 in tools, $275 in parts and $210 in lodging at an RV park. So $545, plus 7 days lost time. A big thanks to Steve at Europarts-SD and the Postal Service for getting the replacement parts to me in only 4 days time, and to NAPA for special ordering the 36mm wrench with it arriving in only 1 day(!).

It's a huge relief to have the belt back on.. especially when reading the forecast for tomorrow night:

"A 20 percent chance of snow showers before midnight. Partly cloudy, with a low around 6."
It sounds like you have learned a few things from this fix/experience... The main thing that you need to learn from this is, don't wait until things break down. Preventive maintenance is very important if you don't want this to happen to you again.

As far as idler pulleys, in the case with INA pulleys, there are 2 of them specified for Sprinters, but the correct one is 532 0234 100 FP02341. See pictures below...
 

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sprint2freedom

2008 NCV3 170ext
It sounds like you have learned a few things from this fix/experience... The main thing that you need to learn from this is, don't wait until things break down. Preventive maintenance is very important if don't want this to happen to you again.
Very true.

As far as idler pulleys, in the case with INA pulleys, there are 2 of them specified for Sprinters, but the correct one is 532 0234 100 FP02341. See pictures below...
Interesting. Unfortunately I already tossed the boxes ,but it looks like I have the narrower ones. Any insight into what the different applications are?

This is what I installed:
Serpentine Belt Idler Pulley 3.0L V6 2007 & LATER Smooth surface, for 7PK belt
 

sprint2freedom

2008 NCV3 170ext
OK, I managed to fish the box out of the trash:
INA 532 0304 100 (FP03041)

So I guess europarts somehow sent me a pair of idlers for the gas engine?
 

Dima74

Independent & Self Reliant - From Chattanooga TN
OK, I managed to fish the box out of the trash:
INA 532 0304 100 (FP03041)

So I guess europarts somehow sent me a pair of idlers for the gas engine?
I'm not 100% certain that they are for a gas engine, but they are not a 100% match to what you had on your Sprinter. They could be from a sedan or suv that uses the same OM642 engine and the belt might be narrower vs the Sprinter.
 
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