Author Topic: Dwell Tach and timing light  (Read 20564 times)

Offline coolmercury

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Dwell Tach and timing light
« on: September 28, 2018, 09:04:23 AM »
Last items from last weeks auction, I needed a dwell tachometer and timing light so couldn't turn these down for $5.00.

Online goodfellow

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Re: Dwell Tach and timing light
« Reply #1 on: September 28, 2018, 09:10:47 AM »
The dwell/tach is a low-cost item, but the timing light is a great deal. At one time that light (with the advance dial adjustment) was quite and expensive item.

Thanks for sharing!

Offline bonneyman

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Re: Dwell Tach and timing light
« Reply #2 on: September 28, 2018, 10:12:20 AM »
The dwell/tach is a low-cost item, but the timing light is a great deal. At one time that light (with the advance dial adjustment) was quite and expensive item.

Thanks for sharing!

^^^ Yep!

Offline J.A.F.E.

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Re: Dwell Tach and timing light
« Reply #3 on: September 28, 2018, 10:52:23 AM »
Stuff looks hardly used.

Not used much anymore by most so they don't carry much value anymore but for $5 that's a steal.
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Offline Uncle Buck

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Re: Dwell Tach and timing light
« Reply #4 on: September 28, 2018, 11:31:08 AM »
At one time that timing light was Sears best and a great piece of equipment. I have one myself. Very well done indeed!
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Offline slip knot

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Re: Dwell Tach and timing light
« Reply #5 on: September 28, 2018, 02:35:29 PM »
That's a nice timing light except for those disconnectable leads. Mine got loose and wouldn't make good contact. a wiggle or two and it would work...for a while... :(

Offline coolmercury

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Re: Dwell Tach and timing light
« Reply #6 on: September 28, 2018, 03:02:39 PM »
Both these still work fine, used them on the 56 Mercury a couple days ago. :)

Offline Uncle Buck

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Re: Dwell Tach and timing light
« Reply #7 on: September 28, 2018, 03:04:21 PM »
That's a nice timing light except for those disconnectable leads. Mine got loose and wouldn't make good contact. a wiggle or two and it would work...for a while... :(

Same thing happened to the first one I had. I just looked around and found another that worked cheap and replaced it. I still like those guns.
You boys better hold on cause I'm gonna have to stand on it!

Offline bonneyman

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Re: Dwell Tach and timing light
« Reply #8 on: September 28, 2018, 10:09:15 PM »
Finally got a nice classic timing light, dwell tach meter, and  engine analyzer and now they're all useless because the Toyota is gone. The other two vehicles are newer, EFI.   >:(

Offline john k

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Re: Dwell Tach and timing light
« Reply #9 on: September 29, 2018, 12:01:20 AM »
Good stuff in their day, I wanted a light  like that so bad but couldn't afford it.    A good deal, but sort of like a chrome plated battery charger that is six volt only. 

Offline Uncle Buck

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Re: Dwell Tach and timing light
« Reply #10 on: September 29, 2018, 05:20:48 AM »
Good stuff in their day, I wanted a light  like that so bad but couldn't afford it.    A good deal, but sort of like a chrome plated battery charger that is six volt only.

I wanted a light  like that so bad but couldn't afford it.  Story of my life, both single and married, especially married with kids.
You boys better hold on cause I'm gonna have to stand on it!

Offline lauver

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Re: Dwell Tach and timing light
« Reply #11 on: January 11, 2019, 09:35:46 PM »
Gang,

A couple of questions about old school dwell/tach's.

Will these tach's work on a 4 cyl with a little math?  If so, what's the correction on the 8 cyl rpm scale?

Also, regarding the timing lights, how do you use these on modern engines with no distributors and no high tension plug wires?

I have the old school equipment but have newer school vehicles...
When my wife leaves me, my dog dies, and they repossess my home, I'll still have my tools.

Online goodfellow

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Re: Dwell Tach and timing light
« Reply #12 on: January 11, 2019, 10:08:42 PM »
AFAIK -- modern vehicles can't be tested with the old analog devices. You need to connect to a high energy spark to trigger the magnetic pickup -- since coils are now directly connected to the plug, then it would take some Rube Goldberg engineering to get the pickup to trigger off the coil pack. The tach/dwell meter is useless in the same manner -- no distributor to hook up to.

The real old lights without the mag pickup were connected in series with the plug wire to the plug through a spring "T" fitting. If you can find one of those lights, and connect it after the coil and make the connection to the plug, then it might trigger the light.  -- BUT for what purpose?

IIRC -- you got a 4cyl reading on the Dwell Tach by doubling the value on the 8cyl scale. -- It's been a while since I've used one of the handheld models though --  :)
« Last Edit: January 11, 2019, 10:18:37 PM by goodfellow »

Offline bonneyman

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Re: Dwell Tach and timing light
« Reply #13 on: January 11, 2019, 10:27:10 PM »
AFAIK -- modern vehicles can't be tested with the old analog devices. You need to connect to a high energy spark to trigger the magnetic pickup -- since coils are now directly connected to the plug, then it would take some Rube Goldberg engineering to get the pickup to trigger off the coil pack. The tach/dwell meter is useless in the same manner -- no distributor to hook up to.

The real old lights without the mag pickup were connected in series with the plug wire to the plug through a spring "T" fitting. If you can find one of those lights, and connect it after the coil and make the connection to the plug, then it might trigger the light.  -- BUT for what purpose?

IIRC -- you got a 4cyl reading on the Dwell Tach by doubling the value on the 8cyl scale. -- It's been a while since I've used one of the handheld models though --  :)

Dang, Ray, is there anything you don't know about cars?  :D

Wish you were local - I'd bring my cars to you to fix ( when you had time in between your own 5 vehicles)!  :-[

Offline Matt_T

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Re: Dwell Tach and timing light
« Reply #14 on: January 12, 2019, 09:11:59 AM »
IIRC -- you got a 4cyl reading on the Dwell Tach by doubling the value on the 8cyl scale. -- It's been a while since I've used one of the handheld models though --  :)

Doubling the scale values or halving the reading should work. I think. Been 20 years since I used a tach on anything bigger than a twin.