Differences in water pump pulleys B21- B230

[VB242]

I know the water pumps and pulleys are different for B21 and B230, my pulley just sheared itself off idling in traffic. I guess I should have used some washers because it looks like it broke around the bolt circle. I have E-fan converted so I guess with the fan clutch attached it would have spread the load better. I did have the belt G-string tight since I'd been having charging issues.

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When the alternator belts came off they took out my turbo oil feed and left a nice slippery spot on the highway
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The state road side assistance guy came by and threw a bunch of kitty litter on the oil puddle on the side of the road but didn't do anything about the stuff that everyone was driving through.

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So another ride home on the rollback, I think she's just getting lazy after 36 years and it was too hot out for her.
2 other state police officers stopped by to check on me, towing dude cut me a break since we only went a couple miles back to the shop, $65.00, seems like a bargain. I think I have another pulley, I will see for sure tomorrow, it's about 5000F in my conex box where my parts are. I may need one though, I'm sure one of youse has one.

Gratuitous cigarette litter pic taken first thing this morning, bad enough they're polluting themselves and the atmosphere but now they're throwing their cancer receipts into the watershed
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[VB242]

Oh yeah, it's my first day back at work since 6/8, still have a 3cm deep gash in my side, could have gone better. Thank goodness I own a Toyota as well with working AC.

 

[pat244ti]

Same thing happened to me on my 760 last year.

I went to a pulley off of a e-fan 940 Turbo, and I used the old face of the sheared pulley to act as a big washer for the bolts that hold it on.

 

[Hoggster]

There is a big and a small pulley for B230s. The small one won't fit on B21/B23s.

 

[VB242]

There is a big and a small pulley for B230s. The small one won't fit on B21/B23s.

Thanks that will help me in my search tomorrow, I think I have 1 of each

 

[VB242]

Same thing happened to me on my 760 last year.

I went to a pulley off of a e-fan 940 Turbo, and I used the old face of the sheared pulley to act as a big washer for the bolts that hold it on.

Good ideas in the washer thing, will copy

 

[neptune]

There is a big and a small pulley for B230s. The small one won't fit on B21/B23s.

Yep. I threw a pulley on my B21ft on the highway when using a small B230 one. Fun education, thankfully it didn't hit any lines like the op's did.

 

[John V outside agitator]

One of these days some of the smrater-er fellers will see why its crazy using the Oafish-al TB oil feed method. Unless I guess you look at self-made drama and possible loss of the whole engine because of a simple rubber belt breaking as fun or exciting.

 

[VB242]

One of these days some of the smrater-er fellers will see why its crazy using the Oafish-al TB oil feed method. Unless I guess you look at self-made drama and possible loss of the whole engine because of a simple rubber belt breaking as fun or exciting.

Yeah perhaps I'll run it off where the oil pressure switch is, is 1/8" npt.

 

[bobxyz]

Kaboom... There goes another water pump pulley.

TLDR: So what caused this? Did I do it myself by over-tightening the alt belts? Old age? Misalignment? I have a spare pulley off a '86 B230F. It's slightly bigger in outer diameter (maybe 1/8"). Will it work correctly or do I need a '85 or earlier B21F pulley?

Long story:
I finally got to use that roadside assistance insurance that I've been paying for, unused, for all these years....

Coming home, I noticed that my automatic transmission was downshifting more often and somewhat unusually. A while later, I heard a hollow wump and thought I'd run over road construction debris. Maybe 30 seconds later, my dashboard lit up, the voltage gauge drops to just +12volts, and the coolant temp (with faker) started creeping up. I pull over and find that my water pump pulley has self destructed.







I did just re-tighten the alt belts ~15 miles ago due to a squeak and soft belts. I thought it was just the hot weather and extra load from the fan clutch. On my engine, there's not a small tightener on the alt belt adjuster. Instead, I barely tighten the main adjuster bolt, pry the alt over with a big screwdriver, and tighten the main bolt. Repeating as needed to get firm belt tension.

The water pump, alternator and fan spin freely, plus the fan was still solidly bolted down, so I don't think they jammed. And there's a belly pan installed so road debris getting wedged in the pulley is highly unlikely. Any guesses at what happened, and how to avoid it in the future?

Fortunately, I pulled over promptly, with no leaking fluids, and only a slightly high coolant temp. It appears that only the pulley and a belt are damaged.

Thanks,
Bob

 

[cleanflametrap]

Absolutely frightening!

I see folks criticizing the belt adjuster design, and replacing the bushings with poly and solid aluminum, but these pics you and the OP have posted convince me I'm on the right track blaming the 3-pulley belt system and its original design not being able to survive the additional load added as the alternators got bigger over the 19 years.

The embarrassing squeal. And our expedient reaction to it with a 10 and 13 wrench (or just 13 if pre-jackscrew) thinking the water pump bearing can take it. A 240 Achilles heel on par with the unreachable cowl cavity and the buttcheek mud collectors.

Of course they needed two belts, and moreso as the alternator pulleys got smaller and the load got bigger, with less than 120 degrees wrap.

What to do (beside getting a 940!)? I dunno.

One thing this thread will do for me is get me off bottom dead center to source some wider belts. Those Volvo and Conti 10mm belts are just wrong for this. I don't want to see the water pump pulley in pieces because I went just a little too far trying to squelch the squeal.

Second thing is I'll again return to the routine of de-glazing the alt pulley and making sure the belts haven't squealed themselves hard and slick.

If it does squeal while it is trying to replenish what the starter took, turn off the lights and fan to let it catch up, I tell the kids.

Thanks guys for this wake-up.

 

[Harry Tuttle]

This happened to me some years ago, but I don't blame any design flaw. After thinking about it, I became convinced that I had left the nuts loose that hold the pulley and fan clutch to the pump. It held on for almost a year, and sometime in that period I found the belts quite loose and tightened them. This no doubt aggravated the situation, as the slack was due to the loose nuts loosening more, and the additional tension was then pulling on a wobbling pulley. I am embarrassed at how blind I was to all that.

I think you are on to something, Art, but I am not sure it applies to cars that are left stock. VB242 has indicated that he has an e-fan on his car, which may raise the electrical load above what the car ever knew, so he may be keeping the belts extra tight. In addition, he says he had no reinforcement over the pulley hub, as a fan clutch would have provided. I am not surprised that his broke.

In Bob's case, who knows? Things do break randomly.

 

[woodenpudden]

Now that I think about it, there is some pretty fierce leverage on the face of that WP pulley if you're using the rearmost groove. Now I'm a touch worried, since I only use 1 v-belt (but my oil feed is in stock location, so that's one less worry)

 

[bobxyz]

When I bought my wagon, it had an electric fan installed with just the flange nuts holding on the water pump pulley. I changed it back to a mechanical fan 1+ years ago. Maybe it was damaged earlier and finally failed?

I also tried the '89 B230 pulley and the grooves don't line up correctly. On closer examination, I found that the B230 pulley has double-thickness metal in section where the studs go through. From the back side, it looks like an extra ~1" tall domed piece has been press fit into the main pulley. I'll post pics later.

I think the best advise from these failures is not to blindly tighten the belts when you notice they're loose. Instead, carefully inspect the pulley for cracking first. In retrospect, I bet my squeaking belts were a symptom of impending pulley failure. I'm curious what I would have found if I'd inspected the pulley before tightening.

 

[Redwood Chair]

 

[VB242]

5VX350 is 1/2" wide belt, 36" outer circumference, this is close to the length of the 15361 belts that I used with the smaller Denso 100 amp alternator pulley. Maybe I will order in a couple and see how they look.

 

[coalminer]

Kaboom... There goes another water pump pulley.

TLDR: So what caused this? Did I do it myself by over-tightening the alt belts? Old age? Misalignment? I have a spare pulley off a '89 B230F. It's slightly bigger in outer diameter (maybe 1/8"). Will it work correctly or do I need a '85 or earlier B21F pulley?

Long story:
I finally got to use that roadside assistance insurance that I've been paying for, unused, for all these years....

Coming home, I noticed that my automatic transmission was downshifting more often and somewhat unusually. A while later, I heard a hollow wump and thought I'd run over road construction debris. Maybe 30 seconds later, my dashboard light up, the voltage gauge drops to just +12volts, and the coolant temp (with faker) started creeping up. I pull over and find that my water pump pulley has self destructed.

I did just re-tighten the alt belts ~15 miles ago due to a squeak and soft belts. I thought it was just the hot weather and extra load from the fan clutch. On my engine, there's not a small tightener on the alt belt adjuster. Instead, I barely tighten the main adjuster bolt, pry the alt over with a big screwdriver, and tighten the main bolt. Repeating as needed to get firm belt tension.

The water pump, alternator and fan spin freely, plus the fan was still solidly bolted down, so I don't think they jammed. And there's a belly pan installed so road debris getting wedged in the pulley is highly unlikely. Any guesses at what happened, and how to avoid it in the future?

Fortunately, I pulled over promptly, with no leaking fluids, and only a slightly high coolant temp. It appears that only the pulley and a belt are damaged.

Thanks,
Bob

I've never seen that happen before, and I've owned a lot of Volvos over the years.

What is strange is how the metal fractured.

It's hard to imagine a sudden failure like that without prior warning. That pulley material is pretty soft, so a fracture like that should have shown symptoms before it totally gave up.
Is there any evidence of a pre-existing hairline fracture on the metal? Any rust on any of the fractured edges?

I always tighten these bolts in a cross pattern. Side to side and snug them all up before the final tightening.
Of course, the metal could have just failed from fatigue.
Having a heavy belt load, especially one that changes randomly with the alternator load would add a lot of additional stress.

It's funny, I've always tightened the belts with the water pump bearings in mind, and trying not to overload them.
I never considered this pulley for failure like this.
Live and learn.

 

[bobxyz]

I've been busy and am finally getting around to posting a followup on my catastrophic water pump pulley failure from a few weeks ago.

Per the OPs original post, here's a picture of a B21 pulley, on the right, and a ~86 B230 pulley, on the left. Notice that the belt spacing doesn't quite match. I don't know if it's close enough or would cause misalignment problems.


Here's a backside pulley picture. Notice the extra domed reinforcing insert in the B230 pulley on the left. I'm guessing that the original B21 pulleys had a high failure rate and that the newer pulleys included the extra domed insert (or casting?) to strengthen the high-stress region of the pulley.


When replacing the pulley&belts, I found another chunk of the old pulley and some fan belt pieces in the belly pan, but nothing else. Based on this, it's extremely unlikely that road construction debris caused the failure.


Looking at the pulley remains, there are cracks all over the place. There's also some reddish deposits on the back side of the pulley, but scratching them shows clean metal. The cracks show some redish, or more bronze-ish, discoloration. I don't know if this is rust, or the equivalent of rust for whatever alloy the pulley is made out of.




My best guess at what happened is as follows:
- The pulley design is marginal and, over time, can fail with stress cracks developing near the bolt holes. In my case, all the cracking is just outside the bolt holes, about where the pulley is sandwiched between the water pump flange and the fan clutch flange.
- As the stress cracks grow, the belts loosen and start to squeal.
- When my belts started to squeal and were soft, I just re-tightened them.
- It's been hot (100+ on the highway) so the mechanical fan clutch would be locked up giving high load on the belts.
- I've been trying to get the factory turbo intercooler over-boost working (briefly bumps boost up to ~10psi when over ~4000rpm). I wasn't romping on it when the pulley failed, but had been earlier in the day. The high rpms most likely accelerated the failure.
- The unexpected downshifting of the automatic transmission was due to AFT being ~1 pint low. My bad, I knew it leaked out a bit when I replaced the speedo drive gear, but didn't check it after finishing the rear axle replacement.
- At some point, the stress cracks expanded far enough to cover most of the bolt hole circle.
- I have no idea what happened in the final instants of failure. It resulted in much more destruction than I'd expect, with broken off and severely bent pieces. The bent pieces must have been caused by the belts spinning the broken pulley into something very solid, causing the major bending, the sheared off belt teeth, and then the belt snapping. The snout of the waterpump is beat up a little, but no chuncks were missing. I tried to bend the big pulley piece back up with my thumbs but couldn't move it. It had to have taken some big forces to bend it originally.

Recommendation:
- If you have a B21FT or other early water pump pulley and your belts start squealing, remove the pulley and carefully inspect it before just tightening the belts.

Are there any bonafide metallurgists here? If so, I'd be glad to send you the pieces if you'll examine them and post your thoughts.

After replacing the pulley, the belts, and topping up the fluids, the wagons running fine again.

-Bob

 

[VolvoLatAm]

For any of you guys running a b230 water pump pulley on a b21/b23 how did the pulleys line up? Bob, you mentioned the grooves didn't line up with the b230 water pump pulley with the added metal thickness at the base?

I am trying to line up a passenger side ps pulley with the water pump pulley--thinking of using a b230 water pump pulley and spacers on the crankshaft pulley...you said 1 inch in difference though? Wow...

 

[bobxyz]

Pics rehosted here - *%#!@ you photobucket, and Thanks Dana!!! It's great being able to directly upload [reasonably resized] pics here.