Got tired of belts coming off
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2005 E55
Got tired of belts coming off
Ever since I installed a larger pulley my belt either shredded or came off. I preferred the later but it still sucked. I did not blame the pulley, by appearance it was perfect (EC btw). It just appeared as though the higher RPM and/or torque would cause the belt to wander off the tensioner pulley. To cure the shredding I softened the sharp edge of the pulley with a sanding block and 180 grit. It worked in the respect that when the belt reached the edge it did not get cut while coming off. However, it still came off.
Upon further review I felt I needed a pulley with lips on it so it would not walk. Unfortunately It appears once you add lips it becomes too wide and contacts the tensioner.
So I made my own. Or more correctly modified one already in existence. Basically I purchased a billet pulley and ground the inside lip off. It worked like a charm. The pulley I modified is easily found on EBay. I would attach a picture but I am on an iPad and was not successful.
1986-1993 MUSTANG 5.0 GT BILLET BELT TENSIONER PULLEY
Upon further review I felt I needed a pulley with lips on it so it would not walk. Unfortunately It appears once you add lips it becomes too wide and contacts the tensioner.
So I made my own. Or more correctly modified one already in existence. Basically I purchased a billet pulley and ground the inside lip off. It worked like a charm. The pulley I modified is easily found on EBay. I would attach a picture but I am on an iPad and was not successful.
1986-1993 MUSTANG 5.0 GT BILLET BELT TENSIONER PULLEY
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From: Southern California
E55 w/ goods, Z32 Project underway
Nice solution. Some pulleys are well know for losing pulleys, nothing to do with tensioner. The welded pulleys do not appear to have this problem, just the multi piece pulleys.
Thread Starter
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2005 E55
- HE (have larger crank pulley and smaller SC i need to address IAT before summer).
- Pump
- Headers
- Belt Wrap.
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From: Puerto Rico
2005 E55 AMG
But it's still pretty rare considering most people here have some sort of pulley. Tensioners go soft and the belts fly off. This happens on lots of cars. I would start by just swapping to another oem tensioner.
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one car at a time
Either your pulley was installed improperly (and is not perfectly true) or your tensioner is bad. There was a post not too long ago from another guy that had his pulley installed incorrectly (they did not align the keyway) and he kept throwing belts.
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Thread Starter
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2005 E55
Is it that rare to throw or shred belts. If others have had this experience can they share what they found? So far my altered billet has worked well. But it would be nice to know what I am bandaging.
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05 White Pano E55, Cadillac CTS-V
As for the tensioner, another member was having belt throwing problems and changed his tensioner and it did nothing to help. He had the same pulley as myself, his was a 172 though that bolts together like this.
We both ended up losing our pulley after several thousand miles too. Bolt backed out and pulley came off the crank. Definitely stick with the welded style pullies, I believe that ASP makes both styles which different retailers sell.
As to the OP, if you do have one of these bolt together style then I would check your crank bolt to be sure it is tight as **** (150ft/lbs) and maybe even consider getting rid of that pulley.
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From: Puerto Rico
2005 E55 AMG
Interesting. Can't see how the pulley design has anything to do with it. I can see how an improperly installed pulley can throw it off if it's not seated properly then the grooves will not align but I'm surprised the pulley will stay on for long if it's improperly installed. My first one was incorrectly installed ( undertorqued it ) and it didn't through belts until the pulley simply fell off. Ouch.
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From: Southern California
E55 w/ goods, Z32 Project underway
I had a multi piece 180 and had several belts fly off and/or shred like mentioned here.
As for the tensioner, another member was having belt throwing problems and changed his tensioner and it did nothing to help. He had the same pulley as myself, his was a 172 though that bolts together like this.
We both ended up losing our pulley after several thousand miles too. Bolt backed out and pulley came off the crank. Definitely stick with the welded style pullies, I believe that ASP makes both styles which different retailers sell.
As to the OP, if you do have one of these bolt together style then I would check your crank bolt to be sure it is tight as **** (150ft/lbs) and maybe even consider getting rid of that pulley.
As for the tensioner, another member was having belt throwing problems and changed his tensioner and it did nothing to help. He had the same pulley as myself, his was a 172 though that bolts together like this.
We both ended up losing our pulley after several thousand miles too. Bolt backed out and pulley came off the crank. Definitely stick with the welded style pullies, I believe that ASP makes both styles which different retailers sell.
As to the OP, if you do have one of these bolt together style then I would check your crank bolt to be sure it is tight as **** (150ft/lbs) and maybe even consider getting rid of that pulley.
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From: Jacksonville, FL
05 White Pano E55, Cadillac CTS-V
Interesting. Can't see how the pulley design has anything to do with it. I can see how an improperly installed pulley can throw it off if it's not seated properly then the grooves will not align but I'm surprised the pulley will stay on for long if it's improperly installed. My first one was incorrectly installed ( undertorqued it ) and it didn't through belts until the pulley simply fell off. Ouch.
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2005 E55
I just looked it is exactly like the one pictured. Actually a ASP 172. I do not know if is the issue or not. In fact I would hate to make that statement without proof. But I did not throw a belt in 2 years of ownership and now I can't keep one on.
Thread Starter
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2005 E55
Interesting. Can't see how the pulley design has anything to do with it. I can see how an improperly installed pulley can throw it off if it's not seated properly then the grooves will not align but I'm surprised the pulley will stay on for long if it's improperly installed. My first one was incorrectly installed ( undertorqued it ) and it didn't through belts until the pulley simply fell off. Ouch.
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From: Jacksonville, FL
05 White Pano E55, Cadillac CTS-V
Especially now that he says he has the same pulley that we all did. Mine was on for like 12,000 miles before it came off and so was Gaspam's.
Last edited by urbamworm; Mar 4, 2013 at 12:18 AM.
Thread Starter
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2005 E55
Well i just spent nearly $300 on a new tensioner and my belts still come off. I am p ssed beyond belief. Why would a vendor sale me a pulley for a lot of money with a rep of coming off? Even if it is replaced I cant get back all of my time and money on this as well as the time and money to replace. My car has been a piece of junk since this mod. WTF
Thread Starter
Junior Member
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2005 E55
good idea. However, I am not just going to eat the cost of this pulley. I bought it new from a sponsor. I would be happy to replace it with the one they give me for free.
