Ford Focus belt idler pulley bolt ?

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I am replacing the alternator in my 2005 Ford Focus with the 2..0L Duratec. The serpentine belt tensioner and idler pulley bearings are bad. My plan is to just to replace the pulleys (bearings) and reusing the original automatic tensioner and idler bolt, spacer etc. I have read some posts at focusfanatics.com about the idler pulley bolt breaking. I don't know how widespread the problem and whether I should use a stronger tension bolt (original is 8.8) or what ? Has anyone here had experience with this issue on the Ford Focus 2005-2007 or other Ford or Mazda in that age range that has the 2.0L or 2.3L Duratec engine ? - Thanks
 
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Middlesex County CT
I have 2006 2.3L in my B2300; it is the longitudinal version. My bolt broke right off while I was driving the vehicle and dropped stuff all over the road; thankfully I was going 25mph on a residential street. I would buy a new one
 
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USA
I would insist that you buy OEM Motorcraft parts for your Idler Pulley and Belt Tensioner that are Made In Canada. These are engineered to exact specification for Duratec engines. Do not buy other brands of inferior quality.
 
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Baltimore, Maryland, USA
Originally Posted by BEETLE
I would insist that you buy OEM Motorcraft parts for your Idler Pulley and Belt Tensioner that are Made In Canada. These are engineered to exact specification for Duratec engines. Do not buy other brands of inferior quality.
I assume that you are referring to the ones made by Litens...
 

rkpatt

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simplegifts- Did you find out or determine the cause of the idler pulley bolt breaking ? Possibly excessive overstressing of the bolt caused by bad pulley bearings, tensioner, WP, PS pump, AC compressor ? Did you replace it with same type of bolt or go back with an upgraded bolt (grade10.9) or some other fix ? Chris142- I have decided to use a new automatic tensioner assembly.
 
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The only thing it could have been is the idler pully; no other accessories were changed as part of the fix. I didn't do the fix as it involved drilling out the old bolt from underneath the vehicle. This happened just about a year ago; i did not investigate a stronger bolt as many other parts of the vehicle will fail prior to the bolt failing again.
 
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USA
There are only a few reports of Idler Pulley bolt breaking on some Duratec engines. Some owners upgraded to the hardest Idler pulley bolt and it still breaks. I think its the abuse of use of vehicle. As far as I know, there are no recalls or TSB set by Ford on this. Ford did not even re-design the Idler bolt pulley> Look at the positive side. There are a lot of Duratec engines out there that have more 250K miles on the odometer and not a single Idler pulley bolt broke on it.
 
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Cincinnati, USA
^ Nope, it's a consistent, repetitive failure on certain engines and has nothing to do with abuse. There is no way to abuse a vehicle to make it happen, should've been a lifetime part but is poorly engineered. It should not have to depend on an extra strong hardened fastener, is simply not engaging good and too small a diameter (hence this topic exists, it is a known issue). The choices are try to find a hardened bolt, which wasn't enough by itself for many owners, grinding the end of the bolt down and putting a nut and lock washer or threadlock on to try to compensate for the worn out threads in the plate where the bolt wobbles, OR the level 3 fix is drill and tap a larger hole for a 10mm bolt which then needs a pulley with a larger inner diameter bearing, for a 10mm bolt instead of 8mm. For example Duralast Idler Pulley 231165 has a 10.15mm I.D. to fit a 10mm bolt.
 
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