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Old 6th February 2020, 19:09   #91
drjonts
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I didn't say it wasn't possible, just very difficult!!
Do you mean adjusting the eccentric mounting and pulley bolt etc . Andy...on the wheel itself (and not compressing the piston of the tensioner to get a pin in it etc.

Jonty
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Old 6th February 2020, 19:10   #92
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Do you mean adjusting the eccentric mounting and pulley bolt etc . Andy...on the wheel itself (and not compressing the piston of the tensioner to get a pin in it etc.

Jonty
Compressing the piston Jonty.
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Old 6th February 2020, 19:13   #93
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Compressing the piston Jonty.
Well, my belt seems to be doing a grand job of retracting it all by itself ...I just leave it a day and it's magically back in almost all the way!!

Perhaps this is further telling me my tensioner is kaput!

Jonty
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Old 7th February 2020, 08:44   #94
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Thanks Simon .... Can you explain a bit more fully how that incorrect adjustment could make the carrier bear on the piston and push it back in please?
You'll understand what I mean when you take off your pulley. The adjustment is eccentric but the operational movement is pivotal. Put those two things together and your brain will quickly turn to guacamole (thanks to Woody Allen). This job calls for pragmatism. Theoretical analysis will get you nowhere. You've made it clear that you're not going to be satisfied without renewing the hydraulic tensioner. The only way to find out the truth and learn from the experience is to first adjust the pulley alone. You can then repeat the "wait and see what happens overnight" test which you've just carried out. Do you have any objections to that?

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Old 7th February 2020, 19:52   #95
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You'll understand what I mean when you take off your pulley. The adjustment is eccentric but the operational movement is pivotal. Put those two things together and your brain will quickly turn to guacamole (thanks to Woody Allen). This job calls for pragmatism. Theoretical analysis will get you nowhere. You've made it clear that you're not going to be satisfied without renewing the hydraulic tensioner. The only way to find out the truth and learn from the experience is to first adjust the pulley alone. You can then repeat the "wait and see what happens overnight" test which you've just carried out. Do you have any objections to that?

Simon
No objections Simon...was just asking for some more details so I could try and get my head round it - all advice gratefully received.

In fact I was last night envisaging lines on a photo of the front belt set up! I was looking at how different tensioner positions would yield different directions to the line of action through the tensioner set-up... and how that would affect the moment through the unit and thus force exerted on the piston once the pulley reaction was resolved in the direction of the piston.

I think I would need to do more sketching and head scratching to work it all out. Getting in there would of course allow me to make adjustments and ascertain what the effect is.

I have read that the likely optimum position of the eccentric mounting when initially setting the tension is with the hexagonal hole in the pulley (when viewed from the front) looks to be in a '4 o'clock' location. Perhaps when I get in there I can check that for a start.

Not had a chance to look at the current position of the tensioner today...will try and pop out there in a bit.

UPDATE - piston still in the extended position that I levered it to and has not retreated yet. Last time I ran the engine up to temperature and when fully cooled that was when it had retreated. I will run the engine tomorrow and see if I can assess the tension of the belt when cold with my little FACOM belt tension tool and when hot to make sure things aren't too tight in the belt train.

Cheers,

Jonty

Last edited by drjonts; 8th February 2020 at 00:17..
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Old 8th February 2020, 19:11   #96
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Hi folks,

After another 'wait and see what happens overnight' I checked the tensioner position and found it to be still extended where I had positioned it - belt seemed tight (hopefully not too tight) so I cranked the engine a few times and looked at the tensioner piston. Still looked ok.

Started the engine no flapping and no undue tight belt type noises - cue happy face! Let it run up to temperature and then stopped the engine for a check and...

...piston pushed back in to where it was when the belt is slack on cold start. Checked now the engine is cool - sure enough, belt is slack once more.

So, it appears that my tensioner set-up / pulley adjustment combo is just able to maintain static belt tension and the pulley backplate is free to rotate on the bolt and not jammed. That's good news. But once the engine runs and applies varying dynamic loads which require the damping action to operate, then this just gradually pushes the piston back in which is then unable to spring back to where it was and maintain tension. Whether that is a feature of the pulley set point when fitted or a weak spring in the tensioner is yet to be confirmed.

I will be back to fill in the gaps when I've stripped it back to look at the belt run and have some more news.

Ciao for now and thanks for reading.

Jonty
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Old 8th February 2020, 19:30   #97
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Hi. In the video I noticed that one of the fastenings holding the cambelt cover on, it looks like it is split. Don’t know if it was done over tightening the cover when the belts were done or if the belt slapping against the cover has caused it. I certainly would not fun the engine until I had found out what was causing the noise. Tensioner I guess.
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Old 8th February 2020, 19:43   #98
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Hi. In the video I noticed that one of the fastenings holding the cambelt cover on, it looks like it is split. Don’t know if it was done over tightening the cover when the belts were done or if the belt slapping against the cover has caused it. I certainly would not fun the engine until I had found out what was causing the noise. Tensioner I guess.
Thanks David.

If that was the video on the first page of all this, Wes made the original post about his problem yonks ago - think he got his all sorted with a full belt service in the end.

Cheers,

Jonty
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Old 8th February 2020, 19:46   #99
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Yea. Cheers jonty Must teach myself to read ALL the posts before coming to a conclusion. Thanks.
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Old 8th February 2020, 19:52   #100
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Thanks David.

If that was the video on the first page of all this, Wes made the original post about his problem yonks ago - think he got his all sorted with a full belt service in the end.

Cheers,

Jonty
You're going to have to bite the bullet Jonty and do the same, still sounds like the tensioner is at fault, will you do it yourself?
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