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940 suddenly started to screech loudly for short periods of time. Not always. Not consistently but only on acceleration.
Water pump has been leaking for a while. I am thinking that might be the source of the screech.
Alternatively it might be the fan.
Any further thoughts?
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So what do we use for a replacement crank pulley?
https://forums.turbobricks.com/showthread.php?t=351495
See the forum member comment about MTC.
iPd has the MTC version:
https://www.ipdusa.com/products/5645/106261-volvo-crankshaft-harmonic-balancer-damper-pulley-aftermarket-vm375-9135194
Amazon sells the MTC version.
https://www.amazon.com/MTC-VM375-9135194-Crankshaft-Vibration/dp/B01CGPTIZ4/
Amazon sells this from brand name Hamburg-Technic. Appears better than an MTC.
https://www.amazon.com/CRANKSHAFT-PULLEY-HARMONIC-BALANCER-9135194/dp/B07BMG55F9
See the comment about Hamburg-Technic.
https://www.bimmerfest.com/threads/warning-hamburg-technic-made-where.1030617/
FCP sells this from Corteco(?). Looks like MTC:
https://www.fcpeuro.com/products/volvo-crankshaft-pulley-240-242-244-245-740-760-780-940-9135194
The assembly is pressed together. Probably when rather warm.
Volvo Genuine Classic Parts in the 240 catalogue, lists two harmoic oscillator crank pulleys for B230/B200:
https://www.gcp.se/en/
For all redblock 4-cylinder models, we have two different dampening crank pulleys?
Up to 1992 is Volvo PN 3514089-6.
1993- is PN 3507751-0 (tasca calls this an intermediate cam t-belt gear)
https://www.tascaparts.com/oem-parts/volvo-intermediate-gear-3507751
The final 1997 GCP 940 catalogue lists PN 9135194-0. NLA says Tasca and Volvo part webstore. GCP parts are warehoused in Sweden.
Yet at Tasca and aftermarket elsewhere is PN 9135194.
Doubtful you want this on your driver daily:
http://www.retroturbo.com/?product=b230-b200-b23-crankshaft-pulley-with-crankshaft-wheel
I've grabbed spare harmonic oscillator crank pulleys from salvage yards.
On my 1991 kittys grey Volvo 240, I installed a new Volvo blue box crank pulley maybe a decade ago. With freely spinning alternator, (non working) AC pulley, and power steering, with headlights on, there is a screech. The alternator, AC, and power steering accessory belts show proper deflection tension when pressed with a thumb. Screeeeeeeeeeech.
Owning these cars continues to be less and less fun. No fun in the prior 20 years anyhoo.
Fabulous Volvo and there crappy documentation, part number method, and terrible documentation.
cheers,
dud.
--
Aaaaaaaay-Murika.
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Screeching is almost unmistakably due to slipping belt:
1) Check belt tension - if already tight then replace with new belt, the old one had glazed. If its still new belt then readjust tightness but do not overtighten. New belts could stretch a bit after several heat cycles especially if installed borderline tight.
2) Use metric sized belts - this is a MUST. Non-metric belts can't have optimal contact (gripping) surface to the metric sized pulley. Microslips could happen then suddenly one day screech!
3) If the AC compressor belt still screeching (after doing no.1) - you'll have to think further up than the belt. There might be issues with the compressor. Its pulley bearing might be on its way out or the compressor itself is failing with extensive wear inside. Prepare to spend more.
4) If the power steering pump belt still screeching (after doing no.1) - the Saginaw steering pump has a high pressure bypass valve to divert excess pressure when steering reaches lock to lock. This bypass valve may be blocked with crud/wear particles. The pump pulley will LOCK if this excess pressure not relieved. Dismantle the high pressure hose at the steering pump to remove the valve for cleaning.
Refer to this GM website for more:
http://www.gmtruckcentral.com/articles/2013/powersteeringmods/
(the website is more about modifying steering pump pressure to provide more steering assist but you'll see where the bypass valve is located)
Regards,
Amarin.
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The PS pump bracket on the 700/900 cars is known to get cocked out of line over time due to the mounting holes becoming elongated. Is the PS pump pulley still aligned properly with the other pulleys?
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Thanks for your input Chris. Is there an effective method of checking alignment other than simply looking at the belts?
Bob
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"...Is there an effective method of checking alignment other than simply looking at the belts?..."
It's more or less an eye ball thing. You can lay a straight edge across the front of the PS pulley and see if it aligns with the front edge of the other pulleys that share the same belt.
By the way, is the power steering belt good and snug?
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Hello Chris,
I was mistaking the air conditioning unit for the power steering unit. My apologies. I am leaning to a defective harmonic pulley at the moment. I went to see about my 240 today and asked the mechanic what he thought might be making the sound on the 940 and he gave me a short education on the harmonic pulley and what happens when the rubber begins to fail.
But I will keep my mind open to other possibilities, as in belts not being aligned. I just wonder if they could make such a loud noise even if misaligned. You can hear this screech across the street.
Bob
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Hi Bob. Unless the A/C belt is obviously way under-tensioned then definitely do as suggested and mark a reference through the crankshaft bolt out to the harmonic balancer outer edge. Bright crayon, office whiteout, house paint, glitter lipstick, anything will do. For that kind of squealing there will be major slippage and totally obvious if that’s the problem, which now seems highly likely. Pulley misalignment is mostly just a contributing factor, something you deal with when installing a new belt or trying to quiet a properly tensioned belt. If it’s not the harmonic balancer or under-tensioning then my bet is that someone has used an aftermarket belt that is too narrow and is now riding bottomed out in one of the pulleys, so do check as I mentioned that the belt surface is riding more or less at the same height as the outer edge of the pulleys. Running a distant fourth is the compressor clutch which can make all kinds of scraping/gritty noises, but not that I’ve heard or seen reported as squealing like a stuck pig.
--
Dave -still with 940's, prev 740/240/140/120 You'd think I'd have learned by now
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Hi Dave,
Marking the crankshaft pulley revealed that it is not at fault. Absolutely no movement between the inner pulley and the outer pulley.
Your advice on the belts appears to be cogent. I am asking my nephew to buy three new belts and we will install them sometime on the weekend. I hope that puts and end to the squealing.
I received a lot of good advice from several sources on this issue and I really appreciate it. I just wish the Jaguar forum was as helpful [my summer car].
Bob
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Great, hope that cures it and it stops startling the neighbours and scaring the cyclists (still beats the heck out of a silent hybrid or electric sneaking up behind you). It was probably due for new belts in any case.
As a note to your nephew, the belts are slightly different sizes for 940 B230F and B230FT and parts houses don't always get it right. The A/C belt is a 13mm belt and for 1994-1995 940 with B230F it's 13x975, with B230FT it's 13x950. The A/C belt is a tight fit to get on/off at the best of times, so I always use the longer 975 belt on my turbo which still leaves more than enough compressor clearance, also means I don't have to keep two sizes hanging on the wall for my other 940. The Alt and P/S belts are 11.9mm belts, and for B230F the Alt is 11.9x1000, P/S is 11.9x1013. For B230FT it's the opposite, Alt is 11.9x1013, P/S is 11.9x1000. Interestingly, the Volvo Pocket Data Book for 1991-1997 900 doesn't list drive belt sizes for the gas engines (but does for the diesels).
Maybe your nephew will consider getting you one of those nifty little Krikit-I tensioning gauges I mentioned as a gift for your efforts. One of my favourite little tools as it helps achieve the proper tension to keep my engines running quietly without putting excessive strain on the pulley bearings, most especially the Alt front bearing. Way more accurate than my uncalibrated thumb. For your added info, the Krikit gauges are made by HMC International in the States and sold by various distributors. The Krikit-I model for V-belts is sold by Dayco as p/n 93865, Gates 91107, and Continental 9001. On Amazon.ca, the best price I see is currently $23.65 CAD +shipping, so you're looking at over $30. I mentioned I got mine at Lordco, something like $18 almost 30 years ago for the Dayco part, and they're currently still carrying them, but under the Gates p/n at $55.69 OTC list price, which is way too much if you don't have an account. I just checked with NAPA here and they're selling it under the Dayco p/n for $22.73, with closest stock to you in Vancouver for overnight delivery. At that price I'd grab it. You can also look at the Krikit-II model for doing wider serpentine belts and timing belts.
If the pulley grooves look a bit too polished, you can always take a little emery cloth or even sandpaper to them. Some people recommend using belt dressing and I used to use it, but it really shouldn't be needed. It doesn't last long so I simply don't bother anymore even though I've still got some on the shelf. As I noted, I find spending a few extra minutes tweaking the A/C pulley alignment a bit helps things stay quieter longer without having to overtension the belt.
--
Dave -still with 940's, prev 740/240/140/120 You'd think I'd have learned by now
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I agree with you - misalignment alone isn't likely to make a really bad screeching noise unless the misalignment caused the belt to loosen up. From the sounds of things you are probably chasing the right rabbit by looking at the harmonic balancer.
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In case you haven't learned this easy trick, you can quickly identify which drive belt is squealing by shooting a fine stream of water at a suspect belt and it will instantly go quiet for a few seconds until the water evaporates. A plant mister works great for this -I now keep one permanently in the garage so I don't have to worry about getting greasy fingeprints on my wife's favourite one. Start with the lower A/C belt and work up, shooting at the inside of the lower belt span close to a pulley so as not to overspray onto a neighbouring belt. Blipping the throttle on a cold engine is usually enough to mimic belt slippage under load. Once the pulley dries and starts to squeal again it will often sound worse for a short while.
Under-tension, glazing and pulley misalignment all contribute to squealing, often in combination, as does a badly worn belt or using too narrow a belt where the belt starts to ride on the bottom of the pulley groove (the surface of the belt should be more or less even with the outer edge of the pulley). Be extra careful when buying aftermarket belts as our engines are spec'd with metric belt widths and lengths with American manufacturers often not make an SAE belt that is close enough, typically erring to a narrower or shorter belt in compatibility charts. For a quick reference, use the Contintal drive belt sizes listed for your engine on FCPEuro, they're usually correct. Continental is an OEM supplier to Volvo (you can also look them up on the Continental web site).
The A/C belt is always a prime suspect for such squealing as you describe under load. If it's only happening when driving at the moment then try engaging and disengaging the A/C to quickly determine if it's the A/C belt. The fatter 13mm A/C belt is on a fairly short span and is most susceptible to pulley misalignment induced noises. Whenever I tension the A/C belt I always use a straight edge on the face of the compressor pulley to get it as close as I can to align with the crank harmonic balancer pulley when tensioned. You can alter the angle of the compressor very slightly by taking advantage of the fact there's a front and rear lock nut. Usually what you need to do is undertension it a bit and lock the rear nut then do the final tension adjustment before locking the front nut -caution, don't break the 10mm adjuster bolt (they're hard to find). Misalignment of the other pulleys can generally only be dealt with by replacing the rubber accessory mounting bushings and making sure you don't overtension -only once have I ever had to resort to shimming behind the accessory mounting brackets to achieve alignment to my satisfaction and I think that was on a dual belted 140 B20F.
I now always use a belt tensioning gauge, much more reliable than the 1/4" thumb deflection or 90 degree twist method. The KRIKIT belt tension gauge (KRIKIT I model) is relatively cheap and very easy to use -I got mine at Lordco years ago, it was in local stock. You can look up the appropriate belt tension specs based on belt width and whether it's a new or used belt on belt manufacturer web sites, like Continental and Gates.
By process of elimination, if it isn't a belt then it's most likely the water pump which you can confirm using a rod (wood or metal) as a stethoscope with your thumb on the end and pushed into your ear if you don't have a proper mechanics stethoscope. If it happens to be the water pump, you can buy yourself a little bit of extra life until you can get around to doing the job by adding water pump lubricant to the coolant.
--
Dave -still with 940's, prev 740/240/140/120 You'd think I'd have learned by now
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We changed the water pump on the car for other reasons. While here it went into its horrendous screech whilst idling. The power steering pulley slows and almost stops while everything else is moving.
Turning the wheel stops the screeching.
It seems like there is a clutch of some sort that is making the noise.
Is there an adjustment of some sort that can be made? Or are we into a power steering unit replacement?
It does not shriek continuously. The belt looks good and pushes in about a half inch. I will see about getting one of the gauges you mention in your reply.
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Hi Bob, We're not talking 940 are we, we're talking your 960 B6304 with the serpentine drive belt, right? I'm not at all familiar with the subtleties of that engine. I looked at the schematics. I wouldn't expect the PS uses either a clutch or a rubber separated harmonic damper pulley on the PS, but maybe it does. Doesn't really look like it in the schematics and I haven't bothered to dig deeper for you. At the same time, if operating the steering changes the load and it goes quiet then maybe it is as you're thinking and a failing PS, in fact my best guess at the moment would be the PS. You've checked PS fluid level I presume? When you say you can turn the pulley face, do you mean the belt turns with it? If that's not the case then the serpentine drive belt is rather undertensioned and the PS bearing may be seizing under load causing the dragging pulley to slip under the moving belt. If the belt does turn with it then it's seemingly more likely as Paul suggests and the harmonic balancer crank pulley has separated, but it would have to be badly separated to be that easy, although those usually don't squeal when they fail, more like a lower frequency vibration sound. Can you check a scribed mark on the crank pulley against the timing cover 0 deg mark at TDC to verify if the harmonic balancer crank pulley is slipping? Hopefully one of our 960 people will chime in with some sage advice.
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Dave -still with 940's, prev 740/240/140/120 You'd think I'd have learned by now
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Hello Dave.
It is the 940. It has one belt that runs from the crankshaft pulley to the power steering and nothing else. As I observed it during one of the screeching episodes, the power steering pulley slowed down and stopped at points while the rest of the engine continued operating at idle speeds.
The noise is very loud when the hood is open. When it started up my nephew's fiance jumped back in fright.
My nephew is the current owner of the car so I don't have immediate access to it at all times. He lives about fifty kilometres from here. He and I changed out the water pump.
It could be the harmonic balancer on the crankshaft end of the belt I suppose. We checked the power steering fluid and it was just at the bottom end of where it should be. My nephew had thought it was the transmission making the noise and he had that fluid level checked. But it would certainly be possible that the fluid level is inadequate.
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If you have a single belt coming off the crankshaft pulley and it's obvious the pulley it's driving is going slower, then it is the harmonic balancer pulley. The two parts can still spin and not separate due to in being a "V"shape internally. You can check for slippage by using a bright gold or white marking pen and draw a straight line from the center big nut to the outer edge of the crank pulley face. Once this is done, run the engine for a minute and the check the line you have made. If the line separates, then you'll know it the harmonic pulley. Does your one belt also drive your alternator ? Believe me, those harmonic balancer will squeal when worn out. The rubber spacing just get old, stiff and cracking until it separates. Harborfreightools sells a mechanics stethoscope for under $5 and is the best tool for finding engine noises as the engine runs. Lets us know what you find.
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I was making a fundamental error. What I thought was the PS pulley is in fact the A/C pulley. This pulley will disengage when the air conditioning is not activated according to my local Volvo expert. That is what I was seeing and it had nothing to do with the screech.
Like you he came to the conclusion immediately that the harmonic pulley is the culprit. I have asked my nephew to follow your directions and to get back to me tonight as to his findings. But I am fairly certain now that the car has a defective harmonic pulley. It looks like an expensive part and my local expert told me that it takes a couple of pretty special tools to take it off and to install another one.
I think the belt to the power steering pump is separate to the others. As I remember, there are three separate belts running.
Thanks for your very valuable input.
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Dear muskox37,
Hope you're well. The only "special" tool needed is a crank counter-hold tool. It keeps the crankshaft from turning, while the crank pulley's bolt is removed.
Some harmonic balancers (crank pulleys) have non-standard (narrow) slots in them, into which fit the crank tool's lugs. I have no idea why a pulley-maker would use a slot, the dimensions of which differed from the Volvo specification. The Volvo-supplied item (and some aftermarket pulley makers) use a slot 7mm-wide, on the narrow axis of the slot. Non-conforming after-market pulley makers use a 6mm-wide slot, so the counter-hold tool won't fit.
In the FAQs, there are other methods to hold the crankshaft, while the crank bolt is removed. Do not use an impact wrench on the crank bolt. When you re-install the crank bolt, a thin coating of anti-seize may be applied. Coat the crankshaft with light oil, to ease installation of the new pulley.
If the timing belt is close to the end of its service life (50K miles) you might want to replace it, before installing the new crank pulley.
Hope this helps.
Yours faithfully,
Spook
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Good day,
Well... when my nephew painted the stripe from the crankshaft nut to the edge of the crankshaft pulley it did not move at all when he drove it to and from his workplace yesterday. The test should have showed it in a few minutes of idling I was told.
I had the air conditioning unit repaired on this car about four years ago so I am going to get in touch with the garage about the screech. Looking for information. Nothing else. I don't expect guarantees over a four year period. Just wondering if the A/C unit could be emitting the noise. What has been your experience?
I am advising my nephew to try squirting water on each belt, starting with the A/C belt when the car screeches.
He was telling me that it scares cyclists if he is anywhere near them and it makes the sound! He thought it a little embarrassing but I got a laugh out of it I have to say.
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Buy a can of "Belt Dressing "Spray....Next time the squeal happens, spray (Using the spray tube) in between the "V" of the pulley and the belt (Engine running) of each accessories pulley just enough (15sec) to see if the squeal goes away. >>>>>Careful<<<<< around the moving part. Try one pulley at a time to see which belt it might be. Never over tighten a belt to stop the squeal. You will put too mush side force on the pulleys. Check your alternator rubber mounting bushing for excessive wear. This can also cause pulley/belt alignment problems. Good Luck......hope you find the squeal,
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The lowest crankshaft pulley is a harmonic balancer pulley. The rubber injected between the crank hub and pulley gets old and slips. Just a thought.
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Dear muskox37,
Hope you're well. Check tension on drive belts. Loose belts can "screech" on acceleration, because loose belts slip.
In the middle of each belt, press downwards with your index finger. If the belt deflects more than 3/16", re-tension the belt.
If the "screech" continues on acceleration, inspect each belt's surface to see if it is "glazed", i.e., shiny. A slipping belt will be "buffed" by the pulleys.
It probably is best to replace any "glazed" belt. I usually replace belts as a set.
If the belts are properly tensioned and none is "glazed", then put a stethoscope on the water pump, while a helper brings engine revs to, say, 2,500 revs/minute. If the water pump "screeches", it is time to replace it.
Do not delay. If the alternator belt is slipping, the alternator is not running at full capacity. That can mean slow battery depletion as days get shorter and headlamps stay on longer.
If the water pump "screeches", the bearing is close to failure. A failed water pump can mean over-heating and a head-gasket job.
Hope this helps.
Stay well!!
Yours faithfully,
Spook
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Hello Spook,
Nice to hear from you again.
We changed out the water pump today for other reasons. It was leaking.
While the car was here it shrieked loudly at one point when idling. Observing the pulleys I could see the power steering pulley slowing while everything else was idling as per usual. When stopped I could move the pulley face myself easily.
It shrieked again and my nephew turned the steering wheel. The shrieking stopped instantly. There is a definite connection here. With the hood up the noise is very loud--do belts scream that loudly?
I am hoping it is just a belt or perhaps not enough fluid in the power steering reservoir. Looks like an expensive unit!
muskox37
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Regarding Spook's use of the term "stethoscope". It needn't be like the kind Dr's use. A long screwdriver with your ear pressed to the handle works well. A long socket extension is another alternative. - Dave
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Things that screech on a car 1. Fan belts 2. brake pads with warning "screechers". -- Dave
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My wife when someone cuts us off!!
--
Post Back. That's whats makes this forum work.
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Surely not a Volvo wife! More like yumpin yimminy!
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