alan
Well-Known Member
I have a friend who has a Volvo MD11D ( or so he says) and the tacho has started to malfunction. At tickover the tack reads virtually nil but at max revs the tacho reads about 1000 r.p.m.
This unit has been working OK for the last 20(?) years and has only recently developed this fault.
Can anybody tell me how the tacho on these engines work; my friend tells me there is a sensor that is the flywheel housing or maybe the timing gear housing (i.e. the tack is not fed from the alternator, as on more modern engines). I owuld like to give him a hand to check out where the problem might be and would appreciate any information on hopw the unit works so I can do some checks with a meter.
Thanks in advance for any help; I'm sure there is someone who has already had this probelm!!
Alan.
This unit has been working OK for the last 20(?) years and has only recently developed this fault.
Can anybody tell me how the tacho on these engines work; my friend tells me there is a sensor that is the flywheel housing or maybe the timing gear housing (i.e. the tack is not fed from the alternator, as on more modern engines). I owuld like to give him a hand to check out where the problem might be and would appreciate any information on hopw the unit works so I can do some checks with a meter.
Thanks in advance for any help; I'm sure there is someone who has already had this probelm!!
Alan.
