2 Documented Engine Failures blaimed on the UR Crank Pulley
05-06-2004, 10:47 AM
#81
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Re: Re: Re: A little more information (o.k. more than a little)
Originally posted by neffster
First off, I'm not planning on installing the pulley so there is no comparison test that I personally will be doing.
Secondly, wouldn't accelerometers which are attached to the pulley cause an inbalance themselves. Wouldn't they create a vibrational mode even if they are equally opposed (they'd never be perfectly opposed right)? Also, attaching a wireless, tri-axial accelerometer would be tricky. Glue would be the only way to attach the accelerometers to the pulley. Ever try adding an EXACT amoung of glue to an EXACT spot? Odds are that the accelerometers themselves would cause as much or more damage than you'd be trying to measure. As you can see this is not an easy task.
For the 2-3% gain, it's not worth my time. I'll stick with my Crawford Plenum, RT Cats, intake and exhaust mods for the time being. Maybe I'll get the TS ECU or something equivalent in the near future, but for now MY pulley debacle is over. If you are not satisfied with the data I've provided, feel free to pick up where I left off. I only ask that you post back here so that others can learn from your hard work. TIA for volunteering ...
First off, I'm not planning on installing the pulley so there is no comparison test that I personally will be doing.
Secondly, wouldn't accelerometers which are attached to the pulley cause an inbalance themselves. Wouldn't they create a vibrational mode even if they are equally opposed (they'd never be perfectly opposed right)? Also, attaching a wireless, tri-axial accelerometer would be tricky. Glue would be the only way to attach the accelerometers to the pulley. Ever try adding an EXACT amoung of glue to an EXACT spot? Odds are that the accelerometers themselves would cause as much or more damage than you'd be trying to measure. As you can see this is not an easy task.
For the 2-3% gain, it's not worth my time. I'll stick with my Crawford Plenum, RT Cats, intake and exhaust mods for the time being. Maybe I'll get the TS ECU or something equivalent in the near future, but for now MY pulley debacle is over. If you are not satisfied with the data I've provided, feel free to pick up where I left off. I only ask that you post back here so that others can learn from your hard work. TIA for volunteering ...
05-06-2004, 02:14 PM
#82
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I guess we will see in the next year or two if there is a number of failures due to this or not. [/B]
So perhaps you want to push that back to 5 years?
Again, all theory, no evidence of damage.
05-06-2004, 03:26 PM
#83
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DrVolkl- Do you even read these threads or do you just type haphazardly to hear the chatter of the keyboard?
Did you even read my post? I'll include a part of it for you...
Then you stated...
Did you even read InfinitiTech's post where he said there were TWO engine failures related to the pulley?
So where exactly did you get lost?
Originally posted by DrVolkl
Again, people keep on forgetting that the pulley has been on the maxima's since they came out in late '01. No problems have been mentioned with those. I should know, I owned one. So perhaps you want to push that back to 5 years?
Again, people keep on forgetting that the pulley has been on the maxima's since they came out in late '01. No problems have been mentioned with those. I should know, I owned one. So perhaps you want to push that back to 5 years?
Originally posted by neffster
…As some of you might understand, there is this other half of me that says there are plenty of other people with UR Pulleys on Nissan Maxima’s with the same VQ35DE who have many miles on their engines. They have allegedly reported no sign of bearing wear, engine damage or anything remotely negative, so why should I worry?…
…As some of you might understand, there is this other half of me that says there are plenty of other people with UR Pulleys on Nissan Maxima’s with the same VQ35DE who have many miles on their engines. They have allegedly reported no sign of bearing wear, engine damage or anything remotely negative, so why should I worry?…
Originally posted by DrVolkl
Again, all theory, no evidence of damage.
Again, all theory, no evidence of damage.
Originally posted by neffster
The following post is from an Infiniti Technician in CA. He claims to have worked on Infiniti's for 13 years... He tells a story of 2 VQ35 engine failures as a DIRECT RESULT OF THE UR Underdrive Crank Pulley.
InfinitiTech (Registered)
05/03/04 08:07 PM
Okay guys,
I could lose my job over this. Here is the information for whatever it is worth.
Case 1:
2003 G35 with 32,566 miles on it, exhaust system, intake manifold and tube, crank pulley. Customer complains of engine knock noise. Isolated it to main bearings making noise. We had the regional engineer come out with his digital stethoscope and that is how we isolated it to the bearings. He used a tool we have called electronic ears, which can actually get a hertz signal from the anything that vibrates. We took the aftermarket pulley off the vehicle and installed it on a similiar 2003, and measured the readings before and after. There was significant difference between the stock pulley and the aftermarket. The motor is balanced internally but balanced with the stock pulley on the motor, maybe the weight difference caused it, who knows. So the engineer boiled it down to the pulley as being the cause of the excessive vibration causing premature wear on the front main bearing.
Case 2:
2003 G35 with 38,334 miles on it. Similiar noise but this vehicle had the stock pulley on it. I myself inspected and worked on this vehicle. But as you all know to the trained eye, I could tell someone had removed the stock pulley. As one of the bolts was almost completely stripped. So logic would tell me, after seeing the usual modifications the engine, intake,intake tube, hi flow cats, exhaust, brakes, etc...One would assume he had the aftermarket pulley on and removed it because he still had warranty on it. I turned a blind eye to the matter and warrantied his motor, and had a little conversation on the side with the customer. He came back later with a case of wine for me and said he deeply appreciated the effort I had done.
There you have it, you guys can decide for yourself after reading that. I am not a referee here, just relaying information to fellow G35 drivers. Maybe it is a fluke this happened to these cars, maybe not. I came to my own conclusion about it. Take it or leave it. Oh yeah the engineer who knows more about the design of these cars agreed as well. By the way, they other guys insurance company bought him a long block, was not covered under warranty…
Infiniti Gearhead
The following post is from an Infiniti Technician in CA. He claims to have worked on Infiniti's for 13 years... He tells a story of 2 VQ35 engine failures as a DIRECT RESULT OF THE UR Underdrive Crank Pulley.
InfinitiTech (Registered)
05/03/04 08:07 PM
Okay guys,
I could lose my job over this. Here is the information for whatever it is worth.
Case 1:
2003 G35 with 32,566 miles on it, exhaust system, intake manifold and tube, crank pulley. Customer complains of engine knock noise. Isolated it to main bearings making noise. We had the regional engineer come out with his digital stethoscope and that is how we isolated it to the bearings. He used a tool we have called electronic ears, which can actually get a hertz signal from the anything that vibrates. We took the aftermarket pulley off the vehicle and installed it on a similiar 2003, and measured the readings before and after. There was significant difference between the stock pulley and the aftermarket. The motor is balanced internally but balanced with the stock pulley on the motor, maybe the weight difference caused it, who knows. So the engineer boiled it down to the pulley as being the cause of the excessive vibration causing premature wear on the front main bearing.
Case 2:
2003 G35 with 38,334 miles on it. Similiar noise but this vehicle had the stock pulley on it. I myself inspected and worked on this vehicle. But as you all know to the trained eye, I could tell someone had removed the stock pulley. As one of the bolts was almost completely stripped. So logic would tell me, after seeing the usual modifications the engine, intake,intake tube, hi flow cats, exhaust, brakes, etc...One would assume he had the aftermarket pulley on and removed it because he still had warranty on it. I turned a blind eye to the matter and warrantied his motor, and had a little conversation on the side with the customer. He came back later with a case of wine for me and said he deeply appreciated the effort I had done.
There you have it, you guys can decide for yourself after reading that. I am not a referee here, just relaying information to fellow G35 drivers. Maybe it is a fluke this happened to these cars, maybe not. I came to my own conclusion about it. Take it or leave it. Oh yeah the engineer who knows more about the design of these cars agreed as well. By the way, they other guys insurance company bought him a long block, was not covered under warranty…
Infiniti Gearhead
05-06-2004, 07:35 PM
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Exactly, there is a HUGE difference between ASSOCIATION (ie. coincident things) and CAUSATION.
It's a big problem in medicine too. The flu may come at certain times of the year, but that's not what causes it.
It's a big problem in medicine too. The flu may come at certain times of the year, but that's not what causes it.
05-07-2004, 03:29 AM
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Thanks for the discussion. For now I think I'm done with my "pulley debacle". After re-reading my last post (after a good nights sleep) I didn't like the way my message came across. I was kind of tough on the original poster, sorry.
Bottom line. Without dampening on the underdrive pulley, you run a much higher risk of engine/bearing failure. Whether you like to admit that fact or not, it's true. Some people might be luckier than others, for those of you who do the install I wish you many troule-free miles.
Thanks again,
-Neffster (heading back to the G35 forums)
Bottom line. Without dampening on the underdrive pulley, you run a much higher risk of engine/bearing failure. Whether you like to admit that fact or not, it's true. Some people might be luckier than others, for those of you who do the install I wish you many troule-free miles.
Thanks again,
-Neffster (heading back to the G35 forums)
05-07-2004, 03:55 AM
#89
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Originally posted by 350zluvr
This came at a really good time for me. I was days away from purchasing an UR crank pulley. I have heard these rumors from others, but have always believed that because our engines are internally balanced we would not have problems with lightened crank pulleys.
Now I'm not sure what the deal is but I'm sure these rumors have not spread so far because of nothing. Why risk it for a measely few horsepower?
This came at a really good time for me. I was days away from purchasing an UR crank pulley. I have heard these rumors from others, but have always believed that because our engines are internally balanced we would not have problems with lightened crank pulleys.
Now I'm not sure what the deal is but I'm sure these rumors have not spread so far because of nothing. Why risk it for a measely few horsepower?
05-07-2004, 04:15 AM
#90
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neffster - thanks
neffster, thanks for taking the time to post that detailed information. Good info.
I knew there had to be a good engineering reason for the rubber ring and multi-part pulley. It is much more expensive than a single piece pulley so I knew the Nissan engineers had SOME reason for putting it there.
I am still not 100% convinced that a solid pulley would cause failures in so few miles, but I am now convinced that if you are going to keep the car for 100K miles the pulleys may not be the best choice for a mod.
Thanks again.
I knew there had to be a good engineering reason for the rubber ring and multi-part pulley. It is much more expensive than a single piece pulley so I knew the Nissan engineers had SOME reason for putting it there.
I am still not 100% convinced that a solid pulley would cause failures in so few miles, but I am now convinced that if you are going to keep the car for 100K miles the pulleys may not be the best choice for a mod.
Thanks again.
05-07-2004, 06:34 AM
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This is more propaganda! By reading the notes that this guy wrote its obvious that he is not very well educated! reads like a 14 year teen wrote the review. You have to realize that this guy is a serviceman at a dealership, not an automive expert by any means. He was probably too stupid to figure out what the real problem was, so blamed it on the cars mods. I'm sure that he picked to pulley as the problem because it is the hardest to understand.
Anyone reading this, don't worry there is a lot of crap that surfaces on this board.
Anyone reading this, don't worry there is a lot of crap that surfaces on this board.
05-07-2004, 07:14 AM
#92
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if someone has a doubt about the pulley then i encourage them not to do it. many of us have gone beyond caring if a part "may" damage our engines. my cai is 100x more likely to kill my engine if i drive thru a puddle, my boltons caused my car to run leaner which may cause my engine to break, my safc changes my maf signal which may malfuntion and bread my ecu or engine. i am at the point now where i dont even think about what might break i think more about what i can do to get more power and make my engine even less reliable. its all part of the game if you dont go all out your never gonna be happy with the results and if you dont want to worry about breaking stuff dont play the game.
05-07-2004, 09:00 AM
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Originally posted by neffster
DrVolkl- Do you even read these threads or do you just type haphazardly to hear the chatter of the keyboard?
Did you even read InfinitiTech's post where he said there were TWO engine failures related to the pulley?
So where exactly did you get lost?
DrVolkl- Do you even read these threads or do you just type haphazardly to hear the chatter of the keyboard?
Did you even read InfinitiTech's post where he said there were TWO engine failures related to the pulley?
So where exactly did you get lost?
Listen to yourself...do you even know who Infinititech is?
I'm done trying to put the flames out on this whole pulley thing. I posted my personal experience as well as my knowledge on the subject from spending 2+ years on maxima.org. You can ask all the scientists you want about theories of engine failure...I'll take my information from the street, not some supposed tech who thinks that some engine MIGHT have failed from the pulley...if those two cars even exist in the first place.
05-07-2004, 09:25 AM
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I believe that the crank pulley can definately have negative effects on an engine. I've had SEVERAL friends with MKIV Supras that experienced crank walk due to the UR crank pulley. That's why I never installed one on my Supra. I did however have the UR accessorie pulleys along with the Powerhouse Racing belt tensioner pulley and experienced no problems with those units.
05-08-2004, 05:03 AM
#95
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I love how they determined causation without even disassembling the engine.......
I see no mention of what kind of oil the guys uses, how much oil was in the car at the time of the "determination", the cars maintenance schedule, etc. etc. Heck if you spend any significant time bouncing off the rev limiter ona bone stock engine you can easily net yourself some rod knock or main bearing knock as well!
The rubber piece in the stock pulley is not there to isolate crank vibration, it is there purely to isolate noise from the accessory pullies (a/c, alternator).
Mike - I hear ya on the Supra. Thing is, thats an I6 engine, which obviously has a significantly longer crank than any V series engine does. I would not put a lightweight pulley on an I-6 engine of ANY make in raw form.....but if you have an engine being built, there is no reason not to use a lightweight pulley. I know personally of a few 1500 hp Supra engines (in pro drag class) using the UR pulley on their cars. Same goes for the BMW engines. Have you guys ever seen the inside of the "almighty" E36 M3 engine? It's a joke quite frankly. And before you guys start thinking we are BMW haters, we have owned/raced E30's, E36's and now an E46 for the last 4 years, so I have a good knowledge base on these engines.
These pullies have been sold for the VQ engine since UR first opened shop many years ago.
Bottom line - don't believe everything you read. Talk to someone who understands the VQ engine.....Might want to also talk to one of the techs at Unorthodox about the construction of their product and the testing they undergo before being released. I am sure they would be more than happy to talk with you about it. I would hardly consider most service techs to be qualified in this regard based on my own personal experience (though I have no doubt there are some good ones out there!).
This is one of those debates that will never end in the aftermarket.
Maybe one day I'll put a call into our buddies at NISMO in Japan and see what they have to say about them.
I see no mention of what kind of oil the guys uses, how much oil was in the car at the time of the "determination", the cars maintenance schedule, etc. etc. Heck if you spend any significant time bouncing off the rev limiter ona bone stock engine you can easily net yourself some rod knock or main bearing knock as well!
The rubber piece in the stock pulley is not there to isolate crank vibration, it is there purely to isolate noise from the accessory pullies (a/c, alternator).
Mike - I hear ya on the Supra. Thing is, thats an I6 engine, which obviously has a significantly longer crank than any V series engine does. I would not put a lightweight pulley on an I-6 engine of ANY make in raw form.....but if you have an engine being built, there is no reason not to use a lightweight pulley. I know personally of a few 1500 hp Supra engines (in pro drag class) using the UR pulley on their cars. Same goes for the BMW engines. Have you guys ever seen the inside of the "almighty" E36 M3 engine? It's a joke quite frankly. And before you guys start thinking we are BMW haters, we have owned/raced E30's, E36's and now an E46 for the last 4 years, so I have a good knowledge base on these engines.
These pullies have been sold for the VQ engine since UR first opened shop many years ago.
Bottom line - don't believe everything you read. Talk to someone who understands the VQ engine.....Might want to also talk to one of the techs at Unorthodox about the construction of their product and the testing they undergo before being released. I am sure they would be more than happy to talk with you about it. I would hardly consider most service techs to be qualified in this regard based on my own personal experience (though I have no doubt there are some good ones out there!).
This is one of those debates that will never end in the aftermarket.
Maybe one day I'll put a call into our buddies at NISMO in Japan and see what they have to say about them.
Last edited by Z1 Performance; 05-08-2004 at 05:18 AM.
05-08-2004, 11:31 AM
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Originally posted by Z1 Performance
...Maybe one day I'll put a call into our buddies at NISMO in Japan and see what they have to say about them.
...Maybe one day I'll put a call into our buddies at NISMO in Japan and see what they have to say about them.
05-10-2004, 11:32 PM
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Paranoid posts running rampant. In cases like this, I almost think the forum is a bad thing. It causes paranoid thoughts in many Z drivers using UR pulleys without substantial proof. That being said, I have noticed a rattling since the install of the crank pulley. I cannot say for sure it is the pulley though, because Borla exhaust has also been reported on this forum as having vibration problems. Maybe the UR pulley is making my exhaust vibrate more, which will lead to my whole car falling apart...
GIVE ME A BREAK!
GIVE ME A BREAK!