'A' Plus chain tensioner

[philthehill]

I have just been reading a non MMOC post (with link) regarding the installation of an 'A' Plus chain tensioner to a Minor 948cc/1098cc engine.

The tensioner appears to have been fitted with the tension pad pivot pin (Pt No: 12G2629) the wrong way round.
The head of the pin should be fitted to the rear of the tensioner mount plate (Pt No: 12G2628). The head of the the pin fits into the drilled hole in the front engine plate.
If the pin is fitted with the head of the pin towards the front/timing case the pin will not be fully home and will foul the timing cover. Also the pin will not be scured correctly in the tensioner mounting plate.
The pin must be fitted the right way round.
Phil

[Declan_Burns]

Phil,
There is also another method rather than drilling a hole in the plate. I used this method which was posted on here many years ago.
It has been on my car for 8 years and no problems.

Regards
Declan

[philthehill]

Declan
Many thanks for your input and diagrams.
I was aware of the rivit/peening method of securing the pin without the need for drilling a hole in the engine front plate.
The link I mentioned above made no reference to any other method of securing the pivot pin, from what is described the pin was fitted from the front with a suitable pin size dia hole drilled in the engine front plate to accomodate the length of the pin, that appears to leave the pin just held in place by the timing cover which is unacceptable.
Whilst you may not have had any problem with the peening solution my preference is to always drill the additional hole in the front engine plate for the head of the pin.
Phil
For gen info:-
The hole in the engine front plate has to be larger (17mm - which is BL size) than the pin head to accommodate the adjustment swing of the tensioner.
The tensioner must not be adjusted so tightly so as to cause rapid wear of the tensioner pad.
The timing chain cover additional cover screw hole in the front engine plate should be made so as to ensure that there is no possibility of oil weep past the timing cover gasket in that area.

[Declan_Burns]

Phil,
I think this is the hole you are referring to.

Regards
Declan

[philthehill]

Declan
That is the one.
It is best if it is utilised and not left redundent.
There is just enough clearance behind the front engine plate to fit a nut/bolt (though I have used a Allen headed bolt to match the other fixings).
I also use the later rubberised timing chain gasket http://www.minispares.com/product/Class ... o%20search which I consider to be much better than the plain card type of gasket.
I never use gasket sealant but I do lightly smear the gasket faces with general purpose grease which keeps the gasket supple and allows the gasket to be easily removed and re-used at a pinch.
Phil