Timing Chain tensioner???

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julianl

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Having fitted the timing chain tensioner twice now incorrectly and consequently snapped the camshaft twice, I am keen to make sure it is all being fitted back correctly. I have followed the instructive advice of dear members when I last posted on this subject and read the instructions and manual and fitted it all back in the correct order. What I would like reassurance on is this:

When fitting the spring into the piston and then the locknut, the piston, naturally, gives a little and begins to press against tension plate. Should this happen and if so what is the difference between fitting the chain tensioner in the correct order rather than as it came out?
 
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Alex Crow

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this quote from one of my posts in your other thread......

"you should have pulled the plunger right out, fitted the tensioner body to the car, then pushed the plunger back in from the other end. when you get it apart again have a look at the design, it has a ratcheting mechanism built into it."

when the mechanism is withdrawn from the engine the spring pushes the plunger forwards - it cannot be pushed back against the internal ratchet mechanism. just have a play with one and all will become crystal.
 
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julianl

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when the mechanism is withdrawn from the engine the spring pushes the plunger forwards - it cannot be pushed back against the internal ratchet mechanism. just have a play with one and all will become crystal.[/QUOTE]

I did play with it for quite a while and understand how it works now but what concerned me was the fact that when I put the plunger in so it sits in the neck of the body that is fine but when I place the spring and locking nut, the spring pushes the plunger out toward the tensioner plate..... is this supposed to happen?
 
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Alex Crow

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errrr, that is how it tensions the timing chain....?!? what would be the point of it if it did not push against the tensioner rail.

you are fitting the spring with the tensioner body installed and the sprockets/chain in place are you not, as per eg haynes manual?
 
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julianl

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yes, exactly following the haynes manual, so what is the difference between doing it the correct way and the way I had done it in the past - except the obvious that the chain is too tight. Is it that the plunger cannot move back far enough? Does oil act as an hydraulic damper?
 

tonychunk

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If the ratchet is not reset and allowed to find its correct setting the length could be too great. To simplify.... imagine if the tensioner was a ordinary bolt and its length was half an inch to take free play off chain. Now imagine that you put a three quarter inch bolt in it would take up the play but then carry on tightning into chain and making way too tight. This is what happened to you.
 

kth286

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It is a spring loaded one way ratchet.

When it was initially removed, it might have moved inwards (tightened) a further notch.

Because you did not reset it, the setting is now too tight, and you put it back into the engine in the 'too tight' condition.
 

Alex Crow

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when the mechanism is withdrawn from the engine the spring pushes the plunger forwards - it cannot be pushed back against the internal ratchet mechanism.

just re-read the above a few times until it makes sense.
 

BlackC55

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Maybe you should let someone who knows how to set them up do it this time?

It may save you another cam.
 

The Crooner

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I cant understand what the problem is.

Anyone who reads my posts knows I make lots of mistakes, but installing the tensioner with reference to Haynes is just plain easy.

Tony
 
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julianl

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I know, I know but what would I do with my weekends and evenings. Besides which I could not afford the £600 - £700 plus I was quoted to do the job in the first place.

The car is only worth £500 on the open market, I need it and my time is free. It is all very gracious of you to offer your advice and time and much thanks to you.

I have now taken the head off and on four times and I am getting pretty quick at it. One day I might get all the bits in the right order and it will work. Fortunately a second hand camshaft only costs me £25.00 including postage each time.
 

Alex Crow

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good for you! keep us up to date with progress.
 

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Maybe I'm being a little dense but What Engine, Age, and Car are we looking at...?

--Might help identify any issues on fitment and re-assembly...
 
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julianl

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H reg. 200 TE Estate 1996cc 4 cylinder, white, around 176000 (haven't looked for a while as it hasn't gone anywhere) underside looks good and clean not much rust so I thought it might be worth doing - don't like throwing things away...

I will not admit to my last mistake after fitting new timing chain and camshaft, you might guess, just checked all the valves and none bent, phew, but will need new cylinder head bolts, they shear out the teeth after tightened and loosed a couple of times so another £33.00 for new mercedes bolts but then check the timing all round fit the tensioner in the right order and hope it works...
 


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