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Tach Dwell Meter

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JPSmit

JPSmit

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I was given a Fox Tach Dwell Meter by a friend. the only problem is that I have no idea how to use it. Are there instructions available anywhere? It didn't come with them.

thanks all
 
How many wires, what color are they(black will always be ground). What does the switch positions say?
 
The tac part could be handy to watch while you're setting your carbs, but most folks don't use the Dwell on Brit cars. Our points are set by gap. old American Iron used the Dwell to set the points. While cranking the engine you watched the dwell meter, then adjusted the screw that could be reached through a little door in the dizzy cap, to bring it in spec. On Lucas Dizzys you have to take everything apart to get to the adjustment so it's far easier to use a feeler guage.
Try and post a pic and we sould be able to give you an idea of how to hook it up.
 
no problem - I'd actually forgotten about this post - will post when I'm back in town
 
It is NO GOOD at all! Send it to me immediately I will dispose of it for you.
*SMILE*
Seriously, as stated a good tach is nice to have to set idle mixtures and curb idle speed. the dwell meter is nice to check dwell angle with after you use the feeler guage or as stated on SOME distributors you can set the dwell with the engine running.
Dwell angle readings are much more acurate than any feeler guage EVER will be.
BUT. having said that on most distributors acheiving the correct dwell angle is a real PITA!
It requires setting the point gap, checking the Dwell angle, if not correct re setting the point gap ECT.ECT. and so on.
 
Banjo said:
Try and post a pic and we should be able to give you an idea of how to hook it up.
Click to expand...

So,finally remembered to take the pics -sorry about the glare. What do I with it that doesn't involve sending it to you?
 

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So, what does the cord out of the bottom look like?

The red thing would be the tach pickup, I assume it has a plug to go into the jack marked 'tach'.

The other gizmo looks like a high current probe (aka shunt), which likely has a plug for the other 'amps' jack.

But there should be some other leads for ohms/volts/dwell.
 
bottom leads attach to the battery

no other leads with it - except that red wire on the right

not sure what a shunt is
 
The meter is made by Fox Valley of Cheboygan Michigan and is from the 70's or early 80's. It is an old analog meter that has been replaced by Hi-impedence digital meters. Do not use this meter on any of the newer cars with computer systems. They run these systems on very low voltages and this meter could back load higher than normal voltage and fry the comp system. In it's day this was a very good,easy to use meter and will work on any vintage British car. The leads are simple to hook up. The two leads on the meter are for the Ohms[resistance]test,voltage[DC only!!!!!] Black for ground,Red for hot[positive] and Dwell test. To hook up for dwell,Black to engine ground[anywhere],red to the primary lead [distributor side of coil Small wire that goes to the points].Select amount of cylinders for engine on meter,look up proper dwell angle of points,start engine and read angle for point setting. If it's in specs bingo!The clip type lead is for inductive tach reading.Hook black and red leads to battery,clip lead to#1 spark plug wire, select tach function anr RPM's.The funky lead is called an amp shunt and is hooked between the battery and the positive cable.It will tell you amperage in the charging system. Careful!!!! misuse can fry meter and charging system. When checking a car with a generator disconnection of battery cable while engine is running will Cause NO HARM! Disconnection of cable on a car with an alternator can fry the alternator!!!! The small red lead is for hooking up in tight places. Internally ,I believe the is a battery for OHM function. On the back of the meter remove the screws holding the four rubber feet,pop off the panel and replace the battery. I hope this info helps you. I have been in the automotive tool and equipment business for 32 years and sold hundreds of these meters in their day.
 
Very efficient tool. I bought one in the 80's when I was working on InBoard motors. Have used it ever since on about every vehicle imagineable including outboards. Go to radio shack and pick up a plug like the one on the red tach and pin pick-up and make yourself a black lead. You'll never be sorry. You will be able to self teach on this one or look around the net for similar tools and read the directions as they all pretty much work the same.
 
John - thanks for the explanation. I'd figured out the tach but the rest is very helpful
 
JP

I'm about 1 hour away from you at the most.
If you ever need help with stuff such as this, just PM me and I'll come over and do what I can.
I have had my Mechanics License for over 35 years and grew up on a tach/dwell meter.

Dave :savewave:

P.S. ask Tinster or Terriphill if you need references.
 
how far are you from Dorchester?

BTW - was trying to set the tach the other week and it kept swinging from 1000 rpm to zero and back. I've been having problems evening out the idle (and starting it) could this be pointing to something?
 
JP
You have a PM

Dave :savewave:
 
got it - check yours
 
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