!!! LET Motorsports Pulley Failure !!!
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Re: !!! LET Motorsports Pulley Failure !!!
Originally Posted by MikeR
I pulled my Idler pulley and got all the dimensions(I think) to do the drawing. I found some scraps that worked out quite well for giving you an idea of how the strap mounts. This is 3/8 aluminum stock, so it is a little thick. But you can see how it will fit and there is plenty of room for the strap. One pic shows the mounting points(circled in black) and then a couple of pics of a mocked up strap with the pulley.
The pulley uses a 10mm bolt, the unused mount we found is a 6mm bolt. The spacing is 3.780",center to center. The idler bearing sits about .475" lower than our strap so that would be what we need for a spacer/seat from out strap. Anyway, here is what it could look like...
MikeR
edit: here is the first pass drawing of the strap and how it fits.
The pulley uses a 10mm bolt, the unused mount we found is a 6mm bolt. The spacing is 3.780",center to center. The idler bearing sits about .475" lower than our strap so that would be what we need for a spacer/seat from out strap. Anyway, here is what it could look like...
MikeR
edit: here is the first pass drawing of the strap and how it fits.
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Re: !!! LET Motorsports Pulley Failure !!!
Here is a drawing with dimensions. I havent gotten a working model done yet. A 2 1/2" 10mm bolt should be about right to put through the strap and spacer and bolt it all together. That would make it easier than the threaded at both ends bolt with a nut.
MikeR
MikeR
Last edited by MikeR; 11-15-2008 at 06:57 PM.
Re: !!! LET Motorsports Pulley Failure !!!
Hey MikeR,
I agree the bolt would be easier. However, my thought was to try and possibly capture the idler if the bearing ever froze again. The original problem is that when the bearing locks up it backs the bolt out and throws the idle into...well whatever ....other pullies, oil cooler, maybe even into the radiator.
So getting a threaded stud and double nutting it to the bracket appears to have an advantage......at least that is my thought.... is it flawed?
Also ideally I would like to get a threaded stud with an unthreaded area where the bearing rests.
I agree the bolt would be easier. However, my thought was to try and possibly capture the idler if the bearing ever froze again. The original problem is that when the bearing locks up it backs the bolt out and throws the idle into...well whatever ....other pullies, oil cooler, maybe even into the radiator.
So getting a threaded stud and double nutting it to the bracket appears to have an advantage......at least that is my thought.... is it flawed?
Also ideally I would like to get a threaded stud with an unthreaded area where the bearing rests.
<--- Huge Horsepower
Re: !!! LET Motorsports Pulley Failure !!!
Originally Posted by 70GT6
Hey MikeR,
I agree the bolt would be easier. However, my thought was to try and possibly capture the idler if the bearing ever froze again. The original problem is that when the bearing locks up it backs the bolt out and throws the idle into...well whatever ....other pullies, oil cooler, maybe even into the radiator.
So getting a threaded stud and double nutting it to the bracket appears to have an advantage......at least that is my thought.... is it flawed?
Also ideally I would like to get a threaded stud with an unthreaded area where the bearing rests.
I agree the bolt would be easier. However, my thought was to try and possibly capture the idler if the bearing ever froze again. The original problem is that when the bearing locks up it backs the bolt out and throws the idle into...well whatever ....other pullies, oil cooler, maybe even into the radiator.
So getting a threaded stud and double nutting it to the bracket appears to have an advantage......at least that is my thought.... is it flawed?
Also ideally I would like to get a threaded stud with an unthreaded area where the bearing rests.
http://www.avweb.com/news/maint/191176-1.html
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Re: !!! LET Motorsports Pulley Failure !!!
70GT6, We dont have any failure analysis on the mounting point but it looks like the bolt just tore out of the aluminum. The couple of pics I have seen show the aluminum casting severly torn up. With the strap and spacer a frozen bearing will not be trying to turn on the bolt head as it does now. I agree that the bolt or stud should not be threaded where the bearing sits on it.
Brian, That is interesting. Do they tie down bolts/nuts that have a rotating force against them? Or is this just for preventing bolts from backing out under vibration?
MikeR
Brian, That is interesting. Do they tie down bolts/nuts that have a rotating force against them? Or is this just for preventing bolts from backing out under vibration?
MikeR
Re: !!! LET Motorsports Pulley Failure !!!
Originally Posted by MikeR
70GT6, We dont have any failure analysis on the mounting point but it looks like the bolt just tore out of the aluminum. The couple of pics I have seen show the aluminum casting severly torn up. With the strap and spacer a frozen bearing will not be trying to turn on the bolt head as it does now. I agree that the bolt or stud should not be threaded where the bearing sits on it.
MikeR
MikeR
From a close look, the damage looks like it occurred whas the bolt backed out and as it got close to the end of its threads the tension from the belt pulled the last few theads through the aluminum.
I thought the series: Stud, idler, nut, (maybe a spacer), bracket, & nut - would "lock" the stud in place and confine the idler in case of bearing failure. Worse case might be breaking a belt if the bearing failed which would be far less damaging.
Last edited by 70GT6; 11-16-2008 at 08:06 AM.
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Re: !!! LET Motorsports Pulley Failure !!!
Is this not just to secure the bolt from backing out in the event of the Bearing giving out?
If so wouldn't it be easier to just pay for the bearing yourself rather than waiting for it to come from Jerry for free?
Any city/town of any size should have a bearing supply house available. The high speed bearing in question sells for under $35.00. Unless you feel your time is totally worthless to fab this part which at best displays it's self as a little rinky dink under the hood.
If anyone wishes to buy but can't find I will hook you up but once again it not only somewhat complicates things but adds S/H to the mix.
Just wondering:?
Mike
PS I too am a little tired of worrying about this LET kit but I don't feel anyone should have to build parts just to keep it from destroying our engine compartments. We all are owed this bearing and in my mind full refunds should be available to anyone that needs to go out and purchase a new bearing due to misengineering.
If so wouldn't it be easier to just pay for the bearing yourself rather than waiting for it to come from Jerry for free?
Any city/town of any size should have a bearing supply house available. The high speed bearing in question sells for under $35.00. Unless you feel your time is totally worthless to fab this part which at best displays it's self as a little rinky dink under the hood.
If anyone wishes to buy but can't find I will hook you up but once again it not only somewhat complicates things but adds S/H to the mix.
Just wondering:?
Mike
PS I too am a little tired of worrying about this LET kit but I don't feel anyone should have to build parts just to keep it from destroying our engine compartments. We all are owed this bearing and in my mind full refunds should be available to anyone that needs to go out and purchase a new bearing due to misengineering.
Last edited by Montana Crossfire; 11-16-2008 at 12:18 PM.
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Re: !!! LET Motorsports Pulley Failure !!!
Here is the mock-up Idler strap installed. The dimensions on the drawing are good. If you use a bolt, it will need to be 2.47" (max) under the head with a 1/4" thick strap. A threaded stud would need to be about 3"- 3 1/4"OAL.
Mike,
With the correct spec bearing installed there should be no real need for a strap/bracket. But the bearing WILL fail eventually. It is more of an insurance thing. Yes, the mock-up is 'rinky dink' looking. I just wanted to get the dimensions right and use stock I had on hand. It can be made lots of different ways with different materials. Should LET have to provide this? Not in my opinion. But anyone that feels the need can now make something using the drawing hole sizes and spacing and it will fit.
As a side note, the idler pulley sitting next to the SC pulley uses a strap/bracket that attaches above the idler and has the idler mounting bolt going through it. It has the engine cover front bracket on it also.
MikeR
Mike,
With the correct spec bearing installed there should be no real need for a strap/bracket. But the bearing WILL fail eventually. It is more of an insurance thing. Yes, the mock-up is 'rinky dink' looking. I just wanted to get the dimensions right and use stock I had on hand. It can be made lots of different ways with different materials. Should LET have to provide this? Not in my opinion. But anyone that feels the need can now make something using the drawing hole sizes and spacing and it will fit.
As a side note, the idler pulley sitting next to the SC pulley uses a strap/bracket that attaches above the idler and has the idler mounting bolt going through it. It has the engine cover front bracket on it also.
MikeR
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Re: !!! LET Motorsports Pulley Failure !!!
I agree with the statement LET should not have to replace this stap. It was the bearing I was refering to and I know they have already said they are willing to do so. It's just that I would like to get out a drive the SRT while Montana's weather permits. I would further more like to do so without worry that the time bomb under the hood may choose to LET go.
Mike
Mike
Re: !!! LET Motorsports Pulley Failure !!!
Originally Posted by Montana Crossfire
I agree with the statement LET should not have to replace this stap. It was the bearing I was refering to and I know they have already said they are willing to do so. It's just that I would like to get out a drive the SRT while Montana's weather permits. I would further more like to do so without worry that the time bomb under the hood may choose to LET go.
Mike
Mike
I have alredy bought a higher speed bearing but if LET finds a better one or redesigns the idler that is the one to get.
Early adoption means we are the test crew....like it or not.
I think LET/Jerry has gone above what is required, but it is also great to she his commitment and his desire to stand behind his product.
Clearly he want to make it the best it can be. if only more companies were a committed.
Last edited by 70GT6; 11-16-2008 at 01:21 PM.
Re: !!! LET Motorsports Pulley Failure !!!
Originally Posted by Montana Crossfire
I agree with the statement LET should not have to replace this stap. It was the bearing I was refering to and I know they have already said they are willing to do so. It's just that I would like to get out a drive the SRT while Montana's weather permits. I would further more like to do so without worry that the time bomb under the hood may choose to LET go.
Mike
Mike
Might not be a bad idea.
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Re: !!! LET Motorsports Pulley Failure !!!
70GT6;
I agree but NEVER in my comment did I imply that LET was not standing behind there product. I just know it will take more time than, as in my statement I said the weather will allow. As far as making it better. Even LET will never be able to design something better than the correct bearing would be for this situation.
And I don't like it when I raise questions to a company and am told research and development had been done only to find out it had not at all. So don't tell me "Like it or not." I wrote an E-mail to LET which is in our attourney's possesion that after viewing the received kit and before installing I asked for a recall on parts of the LET kit because of obvious flaws in the design only to be told there was no way they would recall a until someone was to have issues. My issue then cost me $600.00. Please don't tell me about quailty and standing behind product. I still use LET product so go do your homework.
Mike
I agree but NEVER in my comment did I imply that LET was not standing behind there product. I just know it will take more time than, as in my statement I said the weather will allow. As far as making it better. Even LET will never be able to design something better than the correct bearing would be for this situation.
And I don't like it when I raise questions to a company and am told research and development had been done only to find out it had not at all. So don't tell me "Like it or not." I wrote an E-mail to LET which is in our attourney's possesion that after viewing the received kit and before installing I asked for a recall on parts of the LET kit because of obvious flaws in the design only to be told there was no way they would recall a until someone was to have issues. My issue then cost me $600.00. Please don't tell me about quailty and standing behind product. I still use LET product so go do your homework.
Mike
Re: !!! LET Motorsports Pulley Failure !!!
Guys - I have sent the drawing off to my guy for a formal quote. I will let you know as soon as I have a quote for you. Nice part by the way!
I am going to replace the bearings, so rest assured that you won't have to worry about them much longer.
I am going to replace the bearings, so rest assured that you won't have to worry about them much longer.
Last edited by amg-jerry; 11-17-2008 at 08:00 AM.
Re: !!! LET Motorsports Pulley Failure !!!
Originally Posted by amg-jerry
Guys - I have sent the drawing off the my guy for a formal quote. I will let you know as soon as I have a quote for you. Nice part by the way!
I am going to replace the bearings, so rest assured that you won't have to worry about them much longer.
I am going to replace the bearings, so rest assured that you won't have to worry about them much longer.
We appreciate what you are doing for the crossfire community.
Re: !!! LET Motorsports Pulley Failure !!!
Would everyone mind a bearing that needed to be replaced once a year if it was cost friendly ($14 a year)?
I'm going to consider all options, but there is no guarantee that a $20 bearing will last longer than a $14 one.
Bearings will make noise and fail. Would a once a year replacement be too much?
If not, then I can get them ordered today.
I'm going to consider all options, but there is no guarantee that a $20 bearing will last longer than a $14 one.
Bearings will make noise and fail. Would a once a year replacement be too much?
If not, then I can get them ordered today.