Timing belt whine but tensioner set correctly
#31
There are two timming belt idlers have you replaced the one on the P/S side?
The Techline Case in my post should be available from mitsu dealer.
In my case the noise went away when belt wore in.
Inspect old belt for wear on one edge.
Hard to say where the T/B is on the pulleys in a running engine. So check for rubber residue if it is rubbing it will build up somewhere.
The front lip of the oil pan to the aluminum front cover has shorter bolts 2 or 3 of them. Long typical bolts at that location might hit the belt.
If you are running a Fluidamper crank balancer ( Or other brands) it will rub on the plastic lower timing cover. I had to cut the lip down flat. The OEM damper has a cut out on the back that clears the lip.
Mitsuatb
The Techline Case in my post should be available from mitsu dealer.
In my case the noise went away when belt wore in.
Inspect old belt for wear on one edge.
Hard to say where the T/B is on the pulleys in a running engine. So check for rubber residue if it is rubbing it will build up somewhere.
The front lip of the oil pan to the aluminum front cover has shorter bolts 2 or 3 of them. Long typical bolts at that location might hit the belt.
If you are running a Fluidamper crank balancer ( Or other brands) it will rub on the plastic lower timing cover. I had to cut the lip down flat. The OEM damper has a cut out on the back that clears the lip.
Mitsuatb
Last edited by mitsuatb; Feb 26, 2024 at 06:00 AM.
#32
Evolving Member
Thread Starter
There are two timming belt idlers have you replaced the one on the P/S side?
The Techline Case in my post should be available from mitsu dealer.
In my case the noise went away when belt wore in.
Inspect old belt for wear on one edge.
Hard to say where the T/B is on the pulleys in a running engine. So check for rubber residue if it is rubbing it will build up somewhere.
The front lip of the oil pan to the aluminum front cover has shorter bolts 2 or 3 of them. Long typical bolts at that location might hit the belt.
If you are running a Fluidamper crank balancer ( Or other brands) it will rub on the plastic lower timing cover. I had to cut the lip down flat. The OEM damper has a cut out on the back that clears the lip.
Mitsuatb
The Techline Case in my post should be available from mitsu dealer.
In my case the noise went away when belt wore in.
Inspect old belt for wear on one edge.
Hard to say where the T/B is on the pulleys in a running engine. So check for rubber residue if it is rubbing it will build up somewhere.
The front lip of the oil pan to the aluminum front cover has shorter bolts 2 or 3 of them. Long typical bolts at that location might hit the belt.
If you are running a Fluidamper crank balancer ( Or other brands) it will rub on the plastic lower timing cover. I had to cut the lip down flat. The OEM damper has a cut out on the back that clears the lip.
Mitsuatb
#33
Evolving Member
Thread Starter
Guys I have an update as this might help someone in the future. Ok so the whining noise is from the timing belt but the tensioner is set correctly. What I did I installed on this engine very stiff valve springs (125lbs seat pressure) as my plan was to run 50+psi boost. What the problem is the valve springs are so stiff that when car is running auto tensioner is extending making t belt to tight. Even if I set the pulley tensioner too loose and I rotate the engine the auto tensioner will extend to the point that t belt is too tight because stiff valve springs giving a lot of force. I am wondering if evo 8 t belt would fix the whining because is not kevlar like evo 9 belt is. Or I will need to change the valve springs to little softer probably in 100lbs seat pressure area. Also too tight belt is not good for oil pump so it is making me nervous a little. No wonder I never had this issue previously because I was always using softer springs on past builds, non of them was as extreme as this one.
#34
I don't think you are correct at all with your conclusions. The tensioner operates on the slack side of the belt. So valve spring tension will no change the tension on the slack side. Rubbing on the crank trigger is how the belt makes noise. Look for rubber residue on it. The belt will wear on its edge and noise will stop.
#36
Evolving Member
Thread Starter
I don't think you are correct at all with your conclusions. The tensioner operates on the slack side of the belt. So valve spring tension will no change the tension on the slack side. Rubbing on the crank trigger is how the belt makes noise. Look for rubber residue on it. The belt will wear on its edge and noise will stop.
#37
Evolving Member
Thread Starter
I am very sensitive to the noises but you can hear this whining like crazy. Something like I have a supercharger. And now I am 100% sure it is t belt. I will try evo 8 belt because is not kevlar and if that will not help I will install softer valve springs. What valve spring do you guys use for high hp builds?
#38
EvoM Guru
iTrader: (2)
I am very sensitive to the noises but you can hear this whining like crazy. Something like I have a supercharger. And now I am 100% sure it is t belt. I will try evo 8 belt because is not kevlar and if that will not help I will install softer valve springs. What valve spring do you guys use for high hp builds?
#39
Evolving Member
Thread Starter
I was always using gsc beehive 5041 to all previous builds 500-750whp. They are around 100lbs seat pressure, but on this engine I used Gsc conical springs 125lbs seat pressure as I was aiming for 900-950whp. Do you guys always use evo 9 timing belt or evo 8 belt? I know 9 belt is kevlar it might whine when is too tight.
#40
I run the gates blue racing belt with the blue balancer belt. I had a whine and after 10k or so it went away.
What you see with a static engine is not what is happening when it is running.
Clean the crank trigger and then use a black sharpie to color in the ears. The system is magnetic so will not change operation.
The lightest touch will make the most noise. If it touches at all it will remove the sharpie marks.
The adjuster is supposed to extend as needed. It is a hydraulic damped spring. The initial set position is only that. It will move over time.
I say send it.
What you see with a static engine is not what is happening when it is running.
Clean the crank trigger and then use a black sharpie to color in the ears. The system is magnetic so will not change operation.
The lightest touch will make the most noise. If it touches at all it will remove the sharpie marks.
The adjuster is supposed to extend as needed. It is a hydraulic damped spring. The initial set position is only that. It will move over time.
I say send it.
#41
Evolving Member
Thread Starter
I run the gates blue racing belt with the blue balancer belt. I had a whine and after 10k or so it went away.
What you see with a static engine is not what is happening when it is running.
Clean the crank trigger and then use a black sharpie to color in the ears. The system is magnetic so will not change operation.
The lightest touch will make the most noise. If it touches at all it will remove the sharpie marks.
The adjuster is supposed to extend as needed. It is a hydraulic damped spring. The initial set position is only that. It will move over time.
I say send it.
What you see with a static engine is not what is happening when it is running.
Clean the crank trigger and then use a black sharpie to color in the ears. The system is magnetic so will not change operation.
The lightest touch will make the most noise. If it touches at all it will remove the sharpie marks.
The adjuster is supposed to extend as needed. It is a hydraulic damped spring. The initial set position is only that. It will move over time.
I say send it.
#42
I have the same problem and i’ve been chasing this noise for like 2 summers now, changed all pulleys and belts 2 years ago, first time around the belt was definitely too tight and the whining noise was very loud, I’ve readjusted the tension many times since, gradually loosening it everytime until it was much quieter and I been driving it since (the noise did not get quieter) last week I decided to readjust the tension again, but I set it to the “proper” tension, the whining noise was super loud again… Gonna try just loosening it this week and see if it gets quieter, but I am totally stumped at this point, Evo 9 belt as well, looking to see if your Evo 8 belt would solve it.
#43
Evolving Member
Thread Starter
I have the same problem and i’ve been chasing this noise for like 2 summers now, changed all pulleys and belts 2 years ago, first time around the belt was definitely too tight and the whining noise was very loud, I’ve readjusted the tension many times since, gradually loosening it everytime until it was much quieter and I been driving it since (the noise did not get quieter) last week I decided to readjust the tension again, but I set it to the “proper” tension, the whining noise was super loud again… Gonna try just loosening it this week and see if it gets quieter, but I am totally stumped at this point, Evo 9 belt as well, looking to see if your Evo 8 belt would solve it.
#44
Problem solved
Update, I have discovered the problem... after dealing with this noise for 2 years now...
So I was adjusting the tension again last weekend, since I was fully determinded to eliminate that noise, I just kept adjusting the tension and starting the car in order to see if the noise gets any better, and I have managed to eliminate the whining noise all together, perhaps not for the reason you'd expect though. I've alway used all the Evo timing belt service Youtube videos to get me through the process, but I believe the problem is that in 99% of the videos, they are doing the tension incorrectly...? I was only loosening the tension and starting the car until the noise was significantly quieted down, which didn't make sense to me because I felt like I was basically setting the tension way below spec and that can't be good, but I never questioned the video tutorials because most of them says that they're just following the service manual and there's no further updates on whether there's a whine or not, but of course I don't know if those people have the whine problems, maybe nobody notices the sound or did everyone actually made this mistake?
And nobody will question it either because everyone believes that if the Grenade Pin on the auto tensioner slides in and out, then it is tensioned properly, but when the belt is on so tight like that, the auto tensioner isn't going to move. because there's no slack in the belt, it isn't going to tension it further, so is it really still tensioned "correctly"? Last time when I tensioned again like in the Youtube tutorials, the belt was so tight that my Idle was completely messed up, sitting around 1200rpm at idle and rev hangs ALOT, all these problems were gone after properly tensioning, right now the evo drives perfectly, no belt whine and idle perfectly too, I am extremely happy,
I attached some picture with explanations,
In the service manual, when they tension the pulley, they're pulling 31 inch-pound around 90 degree to the tensioner pulley bolt, which lands the 2 hole nearly fully facing downwards, but in all the Youtube videos I checked, they are doing it straight down, which lands the 2 hole usually between the tensioner arm bolt, in the service manual it basically is just enough tension to cut the slack, rather than really "Tightening".
In all the video tutorials I checked, they're all tensioned the wrong way, the last picture was the only one where it actually looks like how it is in the service manual.
Unless there's some people out there with no belt whine with the "wrong" tension, I believe this is the reason for the belt whine, it's just way too tight.
So I was adjusting the tension again last weekend, since I was fully determinded to eliminate that noise, I just kept adjusting the tension and starting the car in order to see if the noise gets any better, and I have managed to eliminate the whining noise all together, perhaps not for the reason you'd expect though. I've alway used all the Evo timing belt service Youtube videos to get me through the process, but I believe the problem is that in 99% of the videos, they are doing the tension incorrectly...? I was only loosening the tension and starting the car until the noise was significantly quieted down, which didn't make sense to me because I felt like I was basically setting the tension way below spec and that can't be good, but I never questioned the video tutorials because most of them says that they're just following the service manual and there's no further updates on whether there's a whine or not, but of course I don't know if those people have the whine problems, maybe nobody notices the sound or did everyone actually made this mistake?
And nobody will question it either because everyone believes that if the Grenade Pin on the auto tensioner slides in and out, then it is tensioned properly, but when the belt is on so tight like that, the auto tensioner isn't going to move. because there's no slack in the belt, it isn't going to tension it further, so is it really still tensioned "correctly"? Last time when I tensioned again like in the Youtube tutorials, the belt was so tight that my Idle was completely messed up, sitting around 1200rpm at idle and rev hangs ALOT, all these problems were gone after properly tensioning, right now the evo drives perfectly, no belt whine and idle perfectly too, I am extremely happy,
I attached some picture with explanations,
In the service manual, when they tension the pulley, they're pulling 31 inch-pound around 90 degree to the tensioner pulley bolt, which lands the 2 hole nearly fully facing downwards, but in all the Youtube videos I checked, they are doing it straight down, which lands the 2 hole usually between the tensioner arm bolt, in the service manual it basically is just enough tension to cut the slack, rather than really "Tightening".
In all the video tutorials I checked, they're all tensioned the wrong way, the last picture was the only one where it actually looks like how it is in the service manual.
Unless there's some people out there with no belt whine with the "wrong" tension, I believe this is the reason for the belt whine, it's just way too tight.
#45
EvoM Guru
iTrader: (2)
Several people have reported that their cam gears skipped a number of teeth, so I'm not sure if its worth the risk. recently my intake cam gear skipped 3 teeth just trying to start the car with the #4 coil not getting power.
It probably depends on the belt condition/brand. I've had the Gates belt for several t-belt jobs and I haven't heard it whine
It probably depends on the belt condition/brand. I've had the Gates belt for several t-belt jobs and I haven't heard it whine