Tach Trouble

[pistnbroke]

for future reference thats called a Wiggle Test ...usually done first and comes under checking he odvious .......

Great you found it but keep the earth in mind as it may be adequate but only just ..

and it makes a change to the thanked ..we usually get silence...have given you a bit of rep .

[Frosty]

But how could that be Piston, you said "first rule of electrics is any circuit affecting another is earth"

So -- Were you wrong? Surely you were'nt wrong,---- were you.

[BertKu]

Originally Posted by Roger G

I went down to the boat today optimistic about trying pistnbroke's ground fault test. The test connection made no difference, and I do possess the skills to make a proper test. While considering BertKu's soldering repair suggestion I thought I would check the other connections. When I wiggled the signal connection, which was loose, the tach snapped back to being accurate again!

I am new to this forum so I am a little unclear as to how the million dollars factors in but I am sure that as the originator of this thread I must be entitled to a portion of it as well. I'm thinking ten percent or so would do just fine. Thank you all for your help with my issue.

Glad you found the "dry" joint. Must have felt good, when you fixed it, without that it did cost you anything.

With respect to the 10%, I am so sorry, can't help you anymore. I have spent the 500.000 already.
Bert

[pistnbroke]

no frosty I think he has two faults ..I a bad connection which he has found and second a poor earth connection which may give trouble in future.....the only way to test is to put the ( I think it was ) lights on and then put voltmeter bat neg terminal to lamp housings ...if over 0.5v earth is classed as faulty but the system may still work ....he could have very long earth cables ..in a canal boat we use 50 or 75 mm sq on the battery banks ...

[BertKu]

Originally Posted by pistnbroke

no frosty I think he has two faults ..I a bad connection which he has found and second a poor earth connection which may give trouble in future.....the only way to test is to put the ( I think it was ) lights on and then put voltmeter bat neg terminal to lamp housings ...if over 0.5v earth is classed as faulty but the system may still work ....he could have very long earth cables ..in a canal boat we use 50 or 75 mm sq on the battery banks ...

Boy, oh Boy you telling me that I can talk crap, but he has found his fault and you still state that he has another fault. That would be a chance of 1 in the Trillion. He is happy, he found his fault, who are you trying to confuse.

You better pay the million to Frosty.
Bert

[pistnbroke]

An earth is classed a faulty if the drop is over 0.5v ..simple statement of facts .
Unsubscribed bye by

[sdowney717]

in my own case, the tachs sometimes have internal high resistance where the clock spring grounds the internal coil. I am talking of where the tiny clock spring attaches to an adjustable pivot arm used to mechanically set the gauge to a zero point. The tachs have an electric coil and a magnet. When the coil is energized it moves the coil which is directly connected the the rpm pointer. They are sort of like an electric motor in a sense.
a contact cleaner sprayed on the pivot arm and then move it around makes it work again.
perhaps I could add a ground wire solder it to the pivot.

Does anyone have a source for the metal bezels that hold the tach face glass on the front?

[whitepointer23]

Originally Posted by pistnbroke

If turning something on affects it then you have an earthing fault ..try a tempary cable from the tacho to the engine earth ..I assume its driven by the alternator ...

every petrol motor i have had drives the tacho off the coil, not alt like a diesel.