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Old 09-25-2019, 10:47 PM   #1
zedjr10
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Why ps pump, alt and ac pulley belts cause car to vibrate?Harmonic Balancer?

Ok i have had my vibration at idle problem for more than a year. Lately it has gotten worse. Car has been basically rebuilt. I have realized lately my pulley belts vibrate when turning steeering wheel. DOes same thing with ac and when alternator needs a load like turning on headlights.

I thought it might of been my ac since idle drops sometimes but idle don't drop when ac cuts on. Idle will stay the same and car will just have a vibration and get worse at 825 or below.

I keep coming back to harmonic balancer. It must be that.

Can't be iacv as idle don't drop with ac coming on. It just vibrates.

Rear motor mount changed and it got a little worse. Due to Chinese crap which i am changing back soon.

Maybe alternator or voltage regulator but ruled those out also.
If it was alternator then it would vibrate with alternator changes possibly and
not ps pump belt(turning wheel).
If it was voltage regulator my volt readings would be low and they are a bit but not low enough to say VR is bad. It still holds decent volts at higher rpms. It just alternator isn't new and it is a cheap 5 year old autozone one. Maybe i should get a higher amp or a smaller pulley put on.

So back to harmonic balancer, dampener, crankshaft pulley, crankshaft dampener. Whatever u want to call it. I really think harmonic dampener is the best name for it. I am thinking the rubber inside is slowly separating and causing this. The outside of the harmonic balancer is where the ps belt line is and this part would cause the vibrations if rubber was cracked and separating. Doesn't the ps pump need less power than the ac compressor? So all this being true i have to think the Harmonic dampener is my prime suspect. My drivers motor mount hasn't been changed but again what would this have to do when i turn wheel and i get those vibrations or when i turn headlights on and get a slighter vibration for a second.

One last symptom is i can visually see the ps pump shake some and the alternator. The alternator shakes very slightly with the ps pump more but neither are violently.

A possible problem is motor mounts need to be reset but i personally put that in a much lower probability. Anyone got any thoughts?

Oh yeah. All this vibration stops when car rpm is above 900. Below 900 rpm's it just gets worse and worse. Given some accessory is being used like ps , ac or alternator needs to produce more like turning headlights on. At 750 the ps pump is shaking a lot more. The ps pulley has been checked and my car is a manual tranny.

Last edited by zedjr10; 09-26-2019 at 01:23 AM.
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Old 09-26-2019, 04:04 AM   #2
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Is your PS pump pulley bent? (happened to me) IE- is the PS pump wheel/pulley straight?

Does all of this still happen with the PS belt off?
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Old 09-26-2019, 08:31 AM   #3
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Originally Posted by Raf99 View Post
Is your PS pump pulley bent? (happened to me) IE- is the PS pump wheel/pulley straight?

Does all of this still happen with the PS belt off?
it is not the pulley from ps pump, alt or compressor pulley. All been checked. If it was how would it stop above 900 rpm's or cause the alt to slightly shake or any of the symptoms.
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Old 09-26-2019, 09:18 AM   #4
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Quote:
Originally Posted by zedjr10 View Post
it is not the pulley from ps pump, alt or compressor pulley. All been checked. If it was how would it stop above 900 rpm's or cause the alt to slightly shake or any of the symptoms.
The same way a wheel does not vibrate more at higher speeds when unbalanced. But if you are sure it's none of these components then it's going to be your mounts or balancer shafts belt broke.
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Old 09-26-2019, 09:22 AM   #5
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I don't believe it's the harmonic balancer either, or the vibration would increase in frequency with the rpms. You say that it stops above 900 rpm, which sounds like motor mounts to me. Are your balance shafts connected and in time?

You get those higher vibrations when you load the motor at idle (i.e. electrical load, or PS). That's normal. Remove the belt and run the engine for a few seconds, that'll eliminate everything belt related.
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Old 09-26-2019, 01:57 PM   #6
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I don't believe it's the harmonic balancer either, or the vibration would increase in frequency with the rpms. You say that it stops above 900 rpm, which sounds like motor mounts to me. Are your balance shafts connected and in time?

You get those higher vibrations when you load the motor at idle (i.e. electrical load, or PS). That's normal. Remove the belt and run the engine for a few seconds, that'll eliminate everything belt related.
I already removed the ps belt. I don't see how removing both belts would rule it down to harmonic balancer or balancer shaft belt. I guess it would rule out the engine mounts but then there would be no way to put any load on engine and test this. Maybe disconnecting the iacv would achieve this. I have checked the harmonic balance itself and it actually looks ok from outside and while ti is spinning. But who knows.

Is timing balancer belt tensioner hard to adjust. Is there an easy way to do that. This is a strong possibility as it cranks the harmonic balancer.

As far as motor mounts have had the drivers side off and it looks good. Too big of vibration for it just to be old rubber i think.

Thanks for the info. Will have to go see how hard it is to adjust the tension on balancer belt.
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Old 09-26-2019, 02:45 PM   #7
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I don't believe it's the harmonic balancer either, or the vibration would increase in frequency with the rpms. You say that it stops above 900 rpm, which sounds like motor mounts to me. Are your balance shafts connected and in time?

You get those higher vibrations when you load the motor at idle (i.e. electrical load, or PS). That's normal. Remove the belt and run the engine for a few seconds, that'll eliminate everything belt related.
So my balance shaft belt could be broke? Wouldn't oil pump not be working also. So maybe the tension is wrong on belt? My manual shows adjusting both the timing belt tension and balance shaft belts on same adjustment. I must be missing something here.

Ok update after reading some. I think the first thing i can possibly try to do is timing belt tension procedure which i see in my manual. Right? But will that cure the problem if the timing balance tensioner is just a little loose or wasn't pushed down enough before turning pulley and tightening. I am assuming being loose or low tension is causing this vibration. I am still a little confused on how the tensioners are to be tensioned but will read more. Am just scared of effn up my timing.

ok update again. After much more reading i understand how it cant be harmonic balancer and must be balance belt broke or not properly aligned. Would low tension also qualify? Am guessing yes. So really no matter what it seems i will be taking lower timing cover off and crank pulley(harmonic dampener). So next thing i am doing is taking top timing cover off and check what may be wrong. This seems pretty easy and will tell me what is wrong possibly. Right? Thanks for the help and direction . Will chime back in when I take a peek at the belts.

Last edited by zedjr10; 09-26-2019 at 09:02 PM.
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Old 09-27-2019, 06:13 AM   #8
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Quote:
Originally Posted by zedjr10 View Post
So my balance shaft belt could be broke? Wouldn't oil pump not be working also. So maybe the tension is wrong on belt? My manual shows adjusting both the timing belt tension and balance shaft belts on same adjustment. I must be missing something here.

Ok update after reading some. I think the first thing i can possibly try to do is timing belt tension procedure which i see in my manual. Right? But will that cure the problem if the timing balance tensioner is just a little loose or wasn't pushed down enough before turning pulley and tightening. I am assuming being loose or low tension is causing this vibration. I am still a little confused on how the tensioners are to be tensioned but will read more. Am just scared of effn up my timing.

ok update again. After much more reading i understand how it cant be harmonic balancer and must be balance belt broke or not properly aligned. Would low tension also qualify? Am guessing yes. So really no matter what it seems i will be taking lower timing cover off and crank pulley(harmonic dampener). So next thing i am doing is taking top timing cover off and check what may be wrong. This seems pretty easy and will tell me what is wrong possibly. Right? Thanks for the help and direction . Will chime back in when I take a peek at the belts.
Balancer belt broke, naa, i doubt it. Never heard of it happening before. And FYI, the balance shaft belt is different than the timing belt. The vibrating you are talking about is either engine mounts or the harmonic balancer.

Can you take a video of this shaking?
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Old 09-27-2019, 02:13 PM   #9
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Balancer belt broke, naa, i doubt it. Never heard of it happening before. And FYI, the balance shaft belt is different than the timing belt. The vibrating you are talking about is either engine mounts or the harmonic balancer.

Can you take a video of this shaking?
I will take a video. It isn't the motor mounts. Harmonic Dampener would get worse with higher rpms i believe. Which it doesn't. Yes of course i know the timing belt and balance shaft belt is different. Balance belt might not even be on. The mechanic who did this a few years ago has proven to be unreliable so who knows. I will know when i take cover off and check things.
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Old 09-27-2019, 02:20 PM   #10
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No because I am not running a balance shaft belt on my F22B or my H22.

If that were not on the crank pulley you would DEFINITELY notice it.

The shaking probably got worse because of the newer mounts being more stiff than the original ones.

Same thing goes for when you have poly mounts. Less to absorb the vibration.

I doubt it has to do with the belt being too tight. You would hear a
"supercharger" type sound if it is too tight.
*(ahem the manual tensioner swap for H22s)

Is the idle sounding good or rough?
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Old 09-27-2019, 02:54 PM   #11
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No because I am not running a balance shaft belt on my F22B or my H22.

If that were not on the crank pulley you would DEFINITELY notice it.

The shaking probably got worse because of the newer mounts being more stiff than the original ones.

Same thing goes for when you have poly mounts. Less to absorb the vibration.

I doubt it has to do with the belt being too tight. You would hear a
"supercharger" type sound if it is too tight.
*(ahem the manual tensioner swap for H22s)

Is the idle sounding good or rough?
The idle isn't rough. If you turn the wheel or turn ac on it will sometimes drop rpms and shake almost violently while it idles. Power steering itself works perfect. This also is true when alternator needs a load like turning on headlights. Just it only does it for a second. Probably cause of the high instant startup load the device needs.Most of these vibrations are thru steering wheel but sometimes engine vibrations are so bad it shakes front of car.

Another symptom which i think is related is when it is hotter outside with ac on the low end torque is lost. Alot of power lost at rpm's below 2500 rpms. Alot more than it is suppose to be due to compressor cutting on.

The rear mount caused it to shake a little more cause it is chinese crap. Will get around to changing that one day.

Above 900 rpms nothing shakes.

My thinking is it is one of three possibilities. The harmonic dampener(doubtful imo), balance shaft belt(loose or something), or something in timing balancer belt pulley. Like maybe the timing balancer belt pulley isnt in there right but i know nothing about that as i have no ideal how it goes in there. I have seen others who had this same exact problem and it was improper tension on balancer belt. The harmonic dampener i have read would just about always get worse with higher rpms but not totally sure about this.
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Old 09-27-2019, 03:35 PM   #12
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How are your ps & alt belts? Properly tensioned? Is your alt healthy?
This reminds me of my Corolla when I had a very loose serpentine belt.
The idle would fall & cause very bad shaking, especially coming to a stop.

Well the timing belt pulley & balance belt pulley are riding on the same main stud with the timing belt pulley behind the balance belt pulley.

You can actually mess with the balance belt without effecting the timing belt at all with a 10mm bolt that holds the timing belt pulley at it's current tension
so that you can inspect the balance belt. You will be surprised how straight
forward those belts are. You might as well change both belts & do the water pump while you are in there!

Yeah I think your crank pulley is just fine. Double check all the belt tensions.
My F22 had a very loose timing belt that when I floored it the belt had to
catch up like the way a automatic trans sounds lol.
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Old 09-27-2019, 04:37 PM   #13
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Originally Posted by G. Wiffington View Post
How are your ps & alt belts? Properly tensioned? Is your alt healthy?
This reminds me of my Corolla when I had a very loose serpentine belt.
The idle would fall & cause very bad shaking, especially coming to a stop.

Well the timing belt pulley & balance belt pulley are riding on the same main stud with the timing belt pulley behind the balance belt pulley.

You can actually mess with the balance belt without effecting the timing belt at all with a 10mm bolt that holds the timing belt pulley at it's current tension
so that you can inspect the balance belt. You will be surprised how straight
forward those belts are. You might as well change both belts & do the water pump while you are in there!

Yeah I think your crank pulley is just fine. Double check all the belt tensions.
My F22 had a very loose timing belt that when I floored it the belt had to
catch up like the way a automatic trans sounds lol.
All that has been done. It is not the ps or alt belt. Neither is it the ps pulley, alt or compressor. All checked. For sure it isn't those things. Along with misfiring, motor mounts, iacv, fitv, fuel or air system in any way. Timing belt was done less than 10k miles ago with balance belt, seals, water pump and tensioners. I later learned that the mechanic is unreliable. So who knows what short cuts he took. As this vibration has been there since at least he had car.

As far as the 10mm bolt i am not sure what u mean. I am familiar with our timing belt system mostly thru diagrams. I always read they are tensioned together. Both balance and timing belts. I guess i will know more when i look at it myself.

I don't think the timing belt itself is loose as i have no lag in gas pedal to acceleration. Balance belt though who knows.
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Old 09-30-2019, 07:09 PM   #14
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Something i realized today and tested was the cooler it gets outside the less it vibrates even when turning wheel or turning on ac. It is almost a violent vibration at 95 degrees but at 70 degrees it is just an annoying vibration. Not sure if this would point to harmonic balancer or balancer belt. Maybe one of y'all know?

I can think of 2 possibilities pointing to either one. Both are guesses as am not even sure the timing gets retarded during hotter temps.Personally number 1 makes better sense to me. The more i think about 2 i think that isn't the case. Does our timing get retarded the hotter it is?

1. When outside ambient air is hotter the temp sensor in plenum tells computer to retard timing and because balance belt is out of whack it then causes it to vibrate that much more at idle.

2. In hotter temps batteries are less efficient thus the alternator is working heavier. Because the harmonic dampener's rubber is cracked this causes it to vibrate more which then finds its way back out.

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Old 10-03-2019, 04:57 PM   #15
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Anyone's thoughts on this?
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Old 10-04-2019, 03:41 PM   #16
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Temperature definitely effects how our cars run.

Did you ever end up pulling the covers to inspect the balance belt?

I would think maybe if it was hotter than rubber would be more flexible
compared to if it was 32 degrees making the rubber stiffer.

Not to sure about your two thesis statements though.
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Old 10-04-2019, 04:36 PM   #17
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Temperature definitely effects how our cars run.

Did you ever end up pulling the covers to inspect the balance belt?

I would think maybe if it was hotter than rubber would be more flexible
compared to if it was 32 degrees making the rubber stiffer.

Not to sure about your two thesis statements though.
I have not checked balance belt yet. I just got my new pulley and woodruff key. Will be doing it next week. Makes me a bit nervous reading about all the people who afterwards had the crank pulley bolt come off or they sheared it off putting it on. Also not to mention making sure i set the belts right as i have never messed with timing belt. AM looking forward to it in a way. I read that the timing procedure to be used is from 94-97 accord per Honda's update. Which i think the only difference is turning timing belt 3 teeth and not 2 turns. IS this right?

The rubber stretching while hotter is possible but i would think it would be already cracked. These are only 20 degree temp difference causing a much more volatile shake. Which would point to Crank pulley and be an easy fix. Most solutions to this problem though have not been the crank pulley but the balance belts misaligned.

Heat destroys a battery but how and what tolerances am not sure. Cold just makes the electrons move slower. I have a volt-meter and when above 90 degrees my volts are much less even dropping to 11.0 volts when lights and ac are on. Could be an alternator thing also. I just put back on my exhaust header heat shield but seen no difference afterwards. I was sort of hoping my alt would go so could get a higher amp alt. This one is an overpriced autozone one from 6 years ago.

Some cars do retard and advance timing depending on temp readings. This is obd1 so who knows cause i don't. OBD1 doesn't actually read timing but it can change it by a set number of degrees. OBD2 does know your timing and will set it precisely. Retarded timing could very well cause it to shake more thru the balance belts not being lined up in my amateurish opinion.

No matter i am taking it all off next week. Am confident this dysfunctional vibration will be gone soon.
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Old 10-09-2019, 10:23 PM   #18
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Balance shafts were off and i replaced crank pulley also. I can feel a difference. It feels a bit quicker.
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