Pinto cam belt tensioner spring bolt splined bit

[Sparepart]

I have changed a pinto cam belt, but not for a while. I know I have the splined bit that fits the tensioner spring bolt somewhere, BUT where did I put it! ... So many spiders are now homeless in my attempts to locate that strip of 4 or 5 splined sockets/bits....... so I need to buy some more ..... but now I look on-line and am amazed by the number of different splined sockets/bits available, I don't mean different makers, I mean different standards. The one the block that I have looks like it has 12 points, then I see 3 different standards of 12 point splines (at least) depending on the angle between the teeth. I did find a set of bits handed down from my father, but when I tried the one that looked the right diameter it started to go in but was obviouly the wrong tooth angle because it started to make grooves on the sides of the bolt teeth. I searched our extensive database and found the link below, however apart from telling me that a hex key might be ok, there is no definitive information abount exactly the type of splined bit needed. Does anyone here know the details ?

https://www.rhocar.org/index.php?/forums/topic/25924-cam-tensioner/

 

[Sparepart]

I have done some more digging around, and believe I can now answer my own question, which has been raised in other Ford related forums. The type of spline bit needed is XZN "Tripple Square", the profile being three squares overlayed to form 12 corners of 90 degrees equaly spaced around the circle. At least this is what I am going to buy, I will be after an 8 mm bit of this type. A hex key might work but it wouldn't have 90 degree faces, a square drive would probably be a better fit. I'll update this when I get hold of the XZN to try.

In case of interest I am attaching a page from Wikipedia that shows the range screw head types in the world, might be useful if you are trying to find what the head that you see is called.

 

Edited April 17, 2024 by Sparepart
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