!!! LET Motorsports Pulley Failure !!!
Re: !!! LET Motorsports Pulley Failure !!!
Originally Posted by Moparrbust
Well I found a 6303 bearing and put it in to only find yet another noisy problem. Here's what I saw when looking for the noise(and after turning the engine off). This is my wonderful LET waterpump pulley..............
Now it looks like I'm REALLY gonna miss out on the races Friday.
Now it looks like I'm REALLY gonna miss out on the races Friday.
Senior Member
Senior Member
Re: !!! LET Motorsports Pulley Failure !!!
Originally Posted by Bulldogger
Tell me that's the original pulley and not the replacement
I replaced the LET idler pulley bearing tonight.................and the found the damaged LET waterpump pulley.
My car has 2500 miles since 185 pulley setup was installed.
Senior Member
Re: !!! LET Motorsports Pulley Failure !!!
Originally Posted by Bulldogger
Mopar,
Is that the newer version of the water pump pulley or the older style that has the recall on it.
Is that the newer version of the water pump pulley or the older style that has the recall on it.
I guess I must have missed the recall on the water pump pulley as that is from the "original" batch and has never been removed since install...........until tonight.
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Re: !!! LET Motorsports Pulley Failure !!!
Originally Posted by Moparrbust
I replaced the LET idler pulley bearing tonight.................and the found the damaged LET waterpump pulley.
My car has 2500 miles since 185 pulley setup was installed.
My car has 2500 miles since 185 pulley setup was installed.
Re: !!! LET Motorsports Pulley Failure !!!
Mopar, glad that you found that before it completely gave way. Jerry did make an upgraded WP pulley when he did the 181 WP so you can get the replacement. I know that dosent help you for the weekend. Call or email him if you havent already.
Cruzin, the LET WP pulley's are aluminum, not steel.
MikeR
Cruzin, the LET WP pulley's are aluminum, not steel.
MikeR
Senior Member
Re: !!! LET Motorsports Pulley Failure !!!
I just called Jerry and talked to him about it and placed an order(to overnight) the replacement WP pulley. I should get it Thursday with plenty of time to be ready to race Friday night...............as long as my crank pulley doesn't go south(knocks on wood).
Re: !!! LET Motorsports Pulley Failure !!!
It wouldn't hurt to check that crank pulley bolt once in awhile either. I put loctite on mine when I installed it. I'll also be checking all my pulley's every once in a while just to be safe and not have one go out at a really bad time. Factory bearings die too.
MikeR
MikeR
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Re: !!! LET Motorsports Pulley Failure !!!
Originally Posted by amg-jerry
I would also check all hex bolts on the crank pulley to ensure they are nice and tight.
Re: !!! LET Motorsports Pulley Failure !!!
Originally Posted by BrianBrave
I've been researching and inquiring about a replacement bearing - If we want a sealed bearing (like the OEM idler and tensioner bearing) then LET may need to have a special lot run where they use a special High temp PTFE grease.
They have a bearing that's sealed on one side (VS shielded) and rated to 22,000 rpm. This may work- but would still need to be replaced after time as the grease will escape and debris will contaminate the bearing. They also make bearing that's sealed on both sides but it's only rated to 17,000 rpm but using the PTFE grease - it would be rated to 25,000 rpm. I'm trying to find out the minimum lot order.
If not - I plan on re-installing the stock idler pulley and sourcing a bigger belt.
You could always get an unsealed bearing and re-pack grease by hand every 6-12 months. Do you remember your mom showing you how to re-pack bearings by hand? I still remember my first truck - back in those days we didn't have sealed bearings.
I imagine some of you kids are too young and probably spend your youth sitting on the couch playing video games and eating junk food.....
They have a bearing that's sealed on one side (VS shielded) and rated to 22,000 rpm. This may work- but would still need to be replaced after time as the grease will escape and debris will contaminate the bearing. They also make bearing that's sealed on both sides but it's only rated to 17,000 rpm but using the PTFE grease - it would be rated to 25,000 rpm. I'm trying to find out the minimum lot order.
If not - I plan on re-installing the stock idler pulley and sourcing a bigger belt.
You could always get an unsealed bearing and re-pack grease by hand every 6-12 months. Do you remember your mom showing you how to re-pack bearings by hand? I still remember my first truck - back in those days we didn't have sealed bearings.
I imagine some of you kids are too young and probably spend your youth sitting on the couch playing video games and eating junk food.....
I used to have people come to me with siezed crank shaft main bearings on their motorcycles years ago ( I was a motorcycle mechanic ), they had installed standard spec bearings and NOT C3 clearanced - the rpm's and resulting heat caused too much expansion and then seizure. C3's fixed the problem.
Re: !!! LET Motorsports Pulley Failure !!!
Originally Posted by BrianBrave
Interesting - I'm looking at my stock idler pulley and the bearing is marked with a "6303 C3" and the green seals are stamped with "6303 RDD" but with a different type of seal then the bearings used on the LET or ASP (they look impervious to debris)
Now - if "speed limit" is 15,000 RPM - then we have a problem Houston!!
The stock idler pulley is approx 90mm
(178 / 90) = 1.978 * 6,000 engine RPM = 11,667 idler bearing RPM
(181 / 90) = 2.011 * 6,000 engine RPM = 12,067 idler bearing RPM
(185 / 90) = 2.056 * 6,000 engine RPM = 12,336 idler bearing RPM - No problem here.
The LET idler pulley is approx 60mm (and if the ASP idler is the same size):
(178) / 60) = 2.967 * 6,000 Engine RPM = 17,800 idler bearing rpm
(181) / 60) = 3.017 * 6,000 Engine RPM = 18,100 idler bearing rpm
(185) / 60) = 3.083 * 6,000 Engine RPM = 18,498 idler bearing rpm
Can someone verify the ASP idler pulley size and bearing used?
Looks like someone didn't do any math and just copied the OEM bearing part number...
Now - if "speed limit" is 15,000 RPM - then we have a problem Houston!!
The stock idler pulley is approx 90mm
(178 / 90) = 1.978 * 6,000 engine RPM = 11,667 idler bearing RPM
(181 / 90) = 2.011 * 6,000 engine RPM = 12,067 idler bearing RPM
(185 / 90) = 2.056 * 6,000 engine RPM = 12,336 idler bearing RPM - No problem here.
The LET idler pulley is approx 60mm (and if the ASP idler is the same size):
(178) / 60) = 2.967 * 6,000 Engine RPM = 17,800 idler bearing rpm
(181) / 60) = 3.017 * 6,000 Engine RPM = 18,100 idler bearing rpm
(185) / 60) = 3.083 * 6,000 Engine RPM = 18,498 idler bearing rpm
Can someone verify the ASP idler pulley size and bearing used?
Looks like someone didn't do any math and just copied the OEM bearing part number...
Re: !!! LET Motorsports Pulley Failure !!!
Originally Posted by Moparrbust
Well I found a 6303 bearing and put it in to only find yet another noisy problem. Here's what I saw when looking for the noise(and after turning the engine off). This is my wonderful LET waterpump pulley..............
Ok, I figured it out for ya. Get two BIG washers (diameter of the inside of the pulley). Drill four holes for the bolts. Enlarge the center hole so it will fit over the shaft. Now, put one of those washers on the inside of your pulley and one on the outside. Line up the holes and slide it over the shaft. Feed the four bolts through the holes and tighten them.
Problem solved!!!