Blue timing belt warning.
well this was one good read. I have purchased both the eliminator shaft from AMS and Blue Gates belt, so hopefully I can give some input to this once my build is done. There are about 3-4 cars that I know of that are running these two together with zero issues. Lets hope that continues..
A few observations:
- The stub shaft is driven by the pump gear, and shouldn't fail on its own unless being subjected to a severe lateral load or inadequate oiling. I respect AMS' logic that a turned-down shaft checks the severity of lateral force that can be applied to the shaft's front bearing surface, but my personal opinion is this constitutes a treatment of a symptom of an issue rather than the cause. Since a lateral load can only be applied by the pump gear, it's the pump shaft, not the stub shaft that has to be eyed with the most scrutiny.
- The hydraulic belt tensioner appears to react slowly to changes in tension. A stronger, less elastic belt will generate higher frequency harmonics, especially when coupled with greater valvetrain tension (e.g. stiffer springs), and higher rpm. The slow reaction time of the tensioner may allow these harmonics to be transmitted to the pump shaft undampened. This is akin to what happens when a harmonic balancer is removed from the crankshaft. I'm suggesting this because the only object that can subject the pump shaft to lateral loading is the timing belt.
- Speaking of timing belt whine, if you are using adjustable cam gears with an aluminum tooth ring, check for contact surface wear by determining if it's worn through the anodization and/or feeling the edge carefully with a finger. If you have 50k miles on a pair, consider changing them. We isolated this as a cause of whine not long ago. Wow, were mine worn!
- Not long ago, I spun a rod bearing as a result of an errant oil seal at the pump shaft. The oil pump's ability to function properly hinges upon a thousandth or so of clearance between the pump gear and the back of the housing and the pump gear to driven (stub shaft) gear. The ability of the pump to maintain the sensitive clearances that guard the fine line between function and failure ALL boil down to oil film strength at the pump shaft bearing surface. I moved to 15w-50 and installed a Kiggly head oil pressure regulator in an effort to maximize lubrication quality down there.
- Otherwise, it should be taken for granted that valvetrain tension, stronger belts, and higher rpm will subject the pump bearings to greater load. That will always remain a critical point.
- The stub shaft is driven by the pump gear, and shouldn't fail on its own unless being subjected to a severe lateral load or inadequate oiling. I respect AMS' logic that a turned-down shaft checks the severity of lateral force that can be applied to the shaft's front bearing surface, but my personal opinion is this constitutes a treatment of a symptom of an issue rather than the cause. Since a lateral load can only be applied by the pump gear, it's the pump shaft, not the stub shaft that has to be eyed with the most scrutiny.
- The hydraulic belt tensioner appears to react slowly to changes in tension. A stronger, less elastic belt will generate higher frequency harmonics, especially when coupled with greater valvetrain tension (e.g. stiffer springs), and higher rpm. The slow reaction time of the tensioner may allow these harmonics to be transmitted to the pump shaft undampened. This is akin to what happens when a harmonic balancer is removed from the crankshaft. I'm suggesting this because the only object that can subject the pump shaft to lateral loading is the timing belt.
- Speaking of timing belt whine, if you are using adjustable cam gears with an aluminum tooth ring, check for contact surface wear by determining if it's worn through the anodization and/or feeling the edge carefully with a finger. If you have 50k miles on a pair, consider changing them. We isolated this as a cause of whine not long ago. Wow, were mine worn!
- Not long ago, I spun a rod bearing as a result of an errant oil seal at the pump shaft. The oil pump's ability to function properly hinges upon a thousandth or so of clearance between the pump gear and the back of the housing and the pump gear to driven (stub shaft) gear. The ability of the pump to maintain the sensitive clearances that guard the fine line between function and failure ALL boil down to oil film strength at the pump shaft bearing surface. I moved to 15w-50 and installed a Kiggly head oil pressure regulator in an effort to maximize lubrication quality down there.
- Otherwise, it should be taken for granted that valvetrain tension, stronger belts, and higher rpm will subject the pump bearings to greater load. That will always remain a critical point.
Last edited by Ted B; Sep 19, 2009 at 07:48 AM.
First of all, I have absolutlely no problems with AMS. You guys put out some great cars, and most definitely are on top of your marketing.
As far as the stubby shaft/turned down shaft debates go... The instances we are talking about in this thread with the oil pump failures are failures where the drive gear has egg shaped the bore the shaft rides in. Totally different deal, and imo not possible that the driven gear could cause problems with the drive. The other way around sure.
If it wasn't for the fact that balance shaft bearings spin, and balance shaft belts break and take timing belts out with them, I definitely wouldn see anything wrong with running the shaft with the weights turned down. I just do not think its necessary, and keeps the potential problems. Isn't the oil pressure going to be equal all around both gears? If you have 100psi of force on one side of the gear from oil pressure, isn't there going to be 100psi on the opposite side stabilizing it? Also there have been confirmed cases of pump failure with a turned down shaft.
As far as someone needing to nut up... I would hope that you guys already had if you were selling this product.
As far as the stubby shaft/turned down shaft debates go... The instances we are talking about in this thread with the oil pump failures are failures where the drive gear has egg shaped the bore the shaft rides in. Totally different deal, and imo not possible that the driven gear could cause problems with the drive. The other way around sure.
If it wasn't for the fact that balance shaft bearings spin, and balance shaft belts break and take timing belts out with them, I definitely wouldn see anything wrong with running the shaft with the weights turned down. I just do not think its necessary, and keeps the potential problems. Isn't the oil pressure going to be equal all around both gears? If you have 100psi of force on one side of the gear from oil pressure, isn't there going to be 100psi on the opposite side stabilizing it? Also there have been confirmed cases of pump failure with a turned down shaft.
As far as someone needing to nut up... I would hope that you guys already had if you were selling this product.
TTP Quote [The timing belt pulls up on the stub and with no axial brace in the bshaft bearing location to keep it from pulling up diagonally, it will wear out the case.]
I have been a silent observer on this site for over two years. This thread is full of wrong information. I have a Evo IX which I just finished building the motor with a oil pump stub shaft from Buschur Racing. The gentleman from TTP is incorrect. The stubshaft is not the drive gear. The pulley and the shaft that the belt is connected to is supported on both ends. The stub shaft is not tensioned by the CAM BELT. The stub shaft survives without the support of the balance shaft because it is pushed from the meshing of the two gears against the oil pressure it produces on the oppisite side. It was engineered to sort of float in its cavity without it being supported on both ends. The addition of the balance shaft was an afterthought, but it's extra support was an added bonus.
Not trying to bad mouth other venders, if David Buschur uses it on all his motors, you can beleive it works.
Don
I have been a silent observer on this site for over two years. This thread is full of wrong information. I have a Evo IX which I just finished building the motor with a oil pump stub shaft from Buschur Racing. The gentleman from TTP is incorrect. The stubshaft is not the drive gear. The pulley and the shaft that the belt is connected to is supported on both ends. The stub shaft is not tensioned by the CAM BELT. The stub shaft survives without the support of the balance shaft because it is pushed from the meshing of the two gears against the oil pressure it produces on the oppisite side. It was engineered to sort of float in its cavity without it being supported on both ends. The addition of the balance shaft was an afterthought, but it's extra support was an added bonus.
Not trying to bad mouth other venders, if David Buschur uses it on all his motors, you can beleive it works.
Don
Last edited by Roadrunr; Oct 18, 2009 at 10:44 AM. Reason: Grammer
check your water pump, i had the same noise after buschur replaced my serp belt and my water pump had a failure at 30,000 miles ... it will give off the same noise when its shot
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From: Trinidad
i get a similar whine only when warming up. i recently did a timing belt change from OEM to Blue Greddy (same Gates belt - just branded over AFAIK).
from my understanding the whine is from my serpectine belt and not my timing belt. is there anyway to narrow it down and be certain, i would hate to have to disassemble it all
from my understanding the whine is from my serpectine belt and not my timing belt. is there anyway to narrow it down and be certain, i would hate to have to disassemble it all
I am running the Power Enterprises belt that I'm pretty sure is bullet proof
. It was/is a stiff SOB - Almost feels plastic... It's suposed to be the stiffest belt made and they guarentee it not to stretch. That being said. I set the tensioner per Mitsu's recomendation and it is as quiet as the stock belt. It doesn't make any wierd noises either. I'll bet your whining sound is totally based off how you are setting up the tensioner. What your doing does make sense if your only worried about the belt coming loose, but when the engine excellerates there has to be sufficient travel in the opposite direction (compression)for the tensioner to absorb the extra tension placed on the belt. If the tensioner bottoms out, because of lack of travel, you will end up with a belt that is too tight. It will stay tight until the tensioner has a chance to re-adjust.
This post is not intended to imply that you're not justified in your practices with the hydraulic tensioner, but I don't think you can place the fault on the "blue belt" either. I'd bet that your methods of tensioning are not agreeing with the extra stiffness of these kinds of belts and that is the reason for the problem. Peolpe who follow the recomended guidelines for setting up the tensioner will have zero problems with the extra stiffness provided by a " Blue Belt"
. It was/is a stiff SOB - Almost feels plastic... It's suposed to be the stiffest belt made and they guarentee it not to stretch. That being said. I set the tensioner per Mitsu's recomendation and it is as quiet as the stock belt. It doesn't make any wierd noises either. I'll bet your whining sound is totally based off how you are setting up the tensioner. What your doing does make sense if your only worried about the belt coming loose, but when the engine excellerates there has to be sufficient travel in the opposite direction (compression)for the tensioner to absorb the extra tension placed on the belt. If the tensioner bottoms out, because of lack of travel, you will end up with a belt that is too tight. It will stay tight until the tensioner has a chance to re-adjust. This post is not intended to imply that you're not justified in your practices with the hydraulic tensioner, but I don't think you can place the fault on the "blue belt" either. I'd bet that your methods of tensioning are not agreeing with the extra stiffness of these kinds of belts and that is the reason for the problem. Peolpe who follow the recomended guidelines for setting up the tensioner will have zero problems with the extra stiffness provided by a " Blue Belt"
