306 XTdt TDC/RPM sensor location?

Aside from not having the RPM gauge working, I'm assuming (referring
to Haynes wiring diagrams) that the sensor also runs to the ECU.
Whereabouts is the sensor located on a 1995 XTdt? Someone mentioned it
on a forum stating that it was attached to the alternator, but I can't
see anything there - admittedly I haven't had an in-depth look yet.
I'm also guessing it could be on the crankcase somewhere, as it is on
things like the Renault Scenic.
Does anyone know where it is referred to in the Haynes manual at all?
It's not in the index.

 

Then again, totally confused now. Noticed mention of crankshaft
sensor in the DW models section of the manual, but no mention of
such a thing in the XUD section. Mine looks like an XUD - I tried to
check on the front of the engine casing, but the only digits on it
are on two plates. One is small and says D8A and PTC. The other
larger one that is stamped says 10CU6R.

Actually, does the XTdt have an rpm gauge in the console? I'm just
wondering if the display has been replaced with one from a different
model. Mine's got the oil min/maxi and rpm gauges on it.

 

The XUD series engines didn't have any sort of engine management ECU -
some had an immobiliser operating on the stop solenoid, but that's it.
I think that the rpm may well be picked up from the ripple on the 12v
supply to the car from the alternator, in which case you are looking for
something which doesn't exist!

 

That's entirely possible. When I got the car, the fuel gauge didn't
work properly - turned out it was corrosion on the pins for the
connector to the console. I cleaned it up and it worked fine. The
garage I bought it of had fitted another console, but that didn't
work, which led me to check out the connector.
Now that it does work, I'm just wondering if it's got totally the
wrong display in it. The rpm display on the spare console doesn't work
either.

 

There is a sensor on rtheback of the crankcase, it reads the rotation of the
flywheel. Difficult to see, but if you look up from underneath at the part
of the engine to which the gearbox is bolted, above the driveshafts, you
should see it. It needs to be close to the flywheel, and if has moved it
will not work. It might have failed internally too. The connection from it
goes across the top of the bell housing to the front of the block.

 

These are a sod of a job todo. you got a 10mm bolt that holds it in.and
you can do them from the top of the engine bay, well i done mine from
the top and it took about 20 mins to do , but the part is not cheap. it
has 3 wires green, white, and black,or it could be like mine
red.black.yellow.took time to find out which way wires went but that
was easy to do ,

 

I disturbed mine when unbolting the gearbox to get at the clutch on an
XUD 1.9 diesel non-turbo. I tightened it up again but I guess the
slop was to adjust it for something. Does anyone know if this is for
adjustment and if so, how to adjust it?

 

As long as u pushed it right in hard it should still work as i tryed
pulling mine out half way to see if it still works but it did not so
its got to go all the way.

 

Yes it has to go right in. The new ones have a castellation on the end, and
you push it in until it hits the flywheel. The castellations give the right
gap. They wear down in use, so your old one has probably got a smooth end.
Ideally this should just clear the flywheel.