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Discussion Starter #1
I need to replace the front auxiliary idler on my 2.4 JTD 156 10v, 2001 vintage, but it seems to be digging its heels in. It loosens easily but the whole thing turns with the bolt head and after 1/2 a turn it gets tight to point where the bolt feels it will snap.I assume the eccentric adjustment has seized, will this stop the bolt coming out with the adjuster on it? If I can stop the tensioner body turning will it make a difference? When putting the new one on, how do I set the eccentric adjustment? I understand I have to lower the engine to withdraw the bolt fully. Thanks for any advice or experiences!
 

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You need to drop the engine to get the eccentric bolt out on the 20V so assume the 10V is probably the same. You just need to undo the engine mount near to it and lower the engine on a jack.

I don''t recall having any problems getting my old tensioner off. If it is moving then get some WD40 or similar behind it and 'work' it ie repeatedly loosen/tighten until it starts to free off. However, I suspect what has happened is the thread is seized in the block and what you feel moving is the range of movement of the eccentric. In that case be careful......

When all is back together,I made myself a tool to tension the eccentric but its a little tricky. Basically, you tighten the belt with the eccentric until the spring loaded tensioner is correctly tensioned ie when you can pull out the locking pin easily if I remember correctly.

Good luck!

Keith
 

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Thanks, the main tensioner and belt look fairly new so I wasn't going replace them so haven't seen the tensioner close up, all I did to it was put a spanner on it to take the weight off the belt so talk of locking pins is new to me. It looks to me as if the bolt is seized in the idler but free in the air con mount it screws into.There's nothing else holding the idler except the 15mm head bolt in the centre I take it.
 

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I had a look at my old one in the garage and its a simple bolt. Thus, yours shoud just unbolt with a bit of working.

When its off you will notice two holes in the eccentric bearing. They are designed take a special tool to help tensioning. I modified an angle grinder spanner to fit. Others make do with screwdrivers etc. The problem is that you have to turn it the eccentric quite hard as the spring on the main tensioner is quite tough. While its apart it might be worth your while unbolting the main tensioner and stripping, cleaning and regreasing the pivot. Mine was only a year or sold but the pivot was starting on the path to rusting solid.

Keith
 

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I had a look at my old one in the garage and its a simple bolt. Thus, yours shoud just unbolt with a bit of working.

Keith
That's reassuring, I was concerned about snapping the bolt in the mounting but it must be the tensioner that won't turn 360 degrees.
 

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The attached picture should help. The large hole is for the bolt and is simply drilled off-centre into the bearing housing to give you the adjustment by moving the bearing housing.

Keith
 

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Discussion Starter #7
The attached picture should help. The large hole is for the bolt and is simply drilled off-centre into the bearing housing to give you the adjustment by moving the bearing housing.

Keith
Ta, the idler is seized onto the shoulder of the bolt but the two together won't turn more than 180 degrees, the back of the idler must foul something unless it is the end of the bolt knackered. I'll find out next weekend when have round 2, -with the new idler in hand this time!
 

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Are you sure its not just tightening up against the belt? Its designed to spin 360 degrees so there should be nothing fouling if the eccentric is turning when you turn the bolt. As you say, it may be a bit of thread damage causing it too stick. Hopefully free off with working. Good luck! Keith
 

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Discussion Starter #9
The belt was off, I was trying to find the noisy one! Must be the threads in the alloy bracket/bolt. It's very tight, but will have come off.
 

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When my bolt sheared holding that idler on I just took the mounting off,it's not as hard as it looks.
 

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Discussion Starter #11
When my bolt sheared holding that idler on I just took the mounting off,it's not as hard as it looks.
That what this feels as if it is going to do, I was checking there wasn't anything I didn't know about.
 
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