1988 300SE Repalced the A/C compressor. WE loosened the tensoner nut and fan belt came off no problem. This is a three month old tnsioner and shock that were replaced with the water pump (an enlighting experience).
When we put the fan belt back on and tightended the nut it just turned and turned no belt tension.
Looks like from drwaing that this is two peiceces on the threaded rod. We have at least 1 inch of rod past the top nut and both seem to be turning.

Can any one please advise what to do.

We have stopped for this frustrating day and are looking at trying to break the two nuts part and or loosed the 19 MM nut in front of tensioner.

HELP

Thanks Brian

As you tighten the nut (clockwise) the threaded rod should be going DOWN, not up, this tightens the tensioner. It is left-hand thread.
If you are turning the nut and the rod seems to be spinning, either the rod is somehow disconnected from the collar part that attaches to the back of the tensioner, or the rod broke. It can break for several reasons.
When you loosened the tensioner, did you loosen the large central bolt in the tensioner?
You can buy the part which tightens the tensioner (threaded rod, nut and collar piece) as a seperate item.

Gilly

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