My New & First Dwell Meter

[keithb7]

Well, its not new, but it is new to me. I’ve never owned one before. The more old tools I buy to maintain these old cars, my life somehow gets simpler and happier. 
 

It must have probably been 1987 in grade 10 shop class, the last time I used a dwell meter.  I read somewhere that setting the gap with a feeler gauge  is fine for a brand new set of points. Then the first time you file them and set again, the feeler gap method becomes inaccurate. Each time you file it gets progressively worse. 
 

So an old Snap-On dwell meter was justified I figured. Spec for my ‘53 265 is 36-42 deg. I measured 27.  I filed, adjusted and fired it up. New reading 37. Gapped some more measured 40. Good to go! Riveting stuff. 
 

Next I checked the timing. It was out too. Spec 0 deg TDC. Now is back in spec. I also watched the timing advance as I blipped the throttle. Watching the vacuum advance it further. Higher rpm the centrifugal weights take over. Check. All good it seems. 
 

Next was the vacuum gauge. Rock steady at 20 at idle. I used the meter to adjust the idle air mixture screw. Out till the needle started to jump around. Back in till it jumped around. Found a happy middle ground. 
 

Test drive it seems very good. Smooth. Nice steady smooth idle. 
A very satisfying job in today’s digital world. 
 

I will email snap-on for proper literature. I can’t seem to get proper RPM readings. Something tells me I’ve not hooked something up properly to get RPM. 
 

 

[Los_Control]

2 minutes ago, keithb7 said:

will email snap-on for proper literature. I can’t seem to get proper RPM readings. Something tells me I’ve not hooked something up properly to get RPM. 

No idea about the rpm, to me it seems you have a 6 volt positive ground system and a 12 volt negative ground tool.   Maybe does not matter.

 

While the dwell itself is ideal using the meter and not setting the points. With a sbc they made it easy, you can use a Allen wrench while the engine is running, open the window and adjust the dwell.

For the rest of us, we need to manually open and close and adjust and get eventually what is correct dwell., and then set the timing .... back then most never bothered to set the dwell and today I wonder how many know why they should have.

[desoto1939]

I use and old time mechanic tool called a Snap Gap tool.  It was made to be used on several different cars. Basically it has a metal sleeve that goes around the distributor cam. They provide you with a special feeler gage that has a special adapter and then the specific gap feeler bar.  The nice thing is that you do not have to have the dizzy positioned exactly on the high sport of the came to have the poits open and to adjust.  The special gapping tool permits you to gap no matter where the points are located on the cam.

 

If anyone is interested I can take some pictures of the tool and show how you can set the points when the dizzy is in the car and also when it is out of the engine block.

 

Some of the old time mechanics in the group will know about this tool

 

Rich Hartung

desoto1939@aol.com

[keithb7]

Good point on the 6V vs. 12V comparison. I do hook my timing light up to a smaller 12V motorcycle battery that I have.  It won't work on 6V. I'll try doing the same and see if the tach will work.

Edited May 20, 2020 by keithb7

[Los_Control]

Think my point I was trying to make, dwell is important.

Simple things like the rub block on the points will wear out and change the dwell. The breaker plate in the distributor will wear out and change the dwell.

When I was a kid, I owned a dwell meter but never used it. Most people just set points with feeler gauges and called it good.

 

Your post reminds me of a co worker and his nick name was  "Balls" He had a set of brass ones ... he told everyone what he thought.

When talking about setting points with a feeler gauge,  he just laughed and said you do not know what you are doing. And would explain why setting points with a feeler gauge is a good starting point, but not a ending point.

fwiw, he raced a old cj5 jeep with a 327, trailer it to the dirt, race, roll & wreck it, trailer it home and repeat next weekend. And this was before the internet.

 

The dwell meter will help you determine the condition of your distributor if it fluctuates too much while engine is at idle ... just a over looked tool too often forgotten.

[Sniper]

Setting the dwell on a 327 is child's play.  It's a bit more tedious on our distributors.  I generally set it for the mid range of the gap then hook up the meter and check the dwell.  If it's good I am done, if not then I readjust the gap.

[Los_Control]

1 minute ago, Sniper said:

Setting the dwell on a 327 is child's play.  It's a bit more tedious on our distributors.  I generally set it for the mid range of the gap then hook up the meter and check the dwell.  If it's good I am done, if not then I readjust the gap.

You are 100% correct, but today these are project cars ... back then they were daily drivers and we just wanted them to start to get us back and forth to work.

Most never bothered to set the dwell.

 

I am just one of many that never bothered to use the dwell meter, a match book was close enough for me to set the points.

[plymouthcranbrook]

Regarding tach readings my ancient one uses no outside power connection.  Just hook the red lead to either the +or- on the coil depending which ground system you are using and set the scale  then connect the black to ground. Ready to go. I have used it on both pos and neg systems with no trouble.

[Worden18]

Lots of good feedback from everyone.  I always read everyone's posts and try to learn something.

Congrats on the meter Keith.  I have one similar to yours that I used to set the dwell on my 69 Impala (327).  Bought it about 30 years ago.  Hadn't used it in 25 until the other night when I rediscovered it and checked the idle rpm on the Meadowbrook.  It's not set up for a 6v +ground, so I put the red lead on positive ground post and the black lead on negative.  Set the switch on 6cyl and hooked up the other wire/plug thingy (damn if I know the correct term) to#1 spark plug.  Tach worked just fine.  I was about 50rpm low on idle and also when engaging fluid drive.  Should've been at 450rpm for fluid drive...I was at 400.  I'll post a pic of my meter in my thread later.

[keithb7]

Out for a cruise tonight  I notice a very smooth idle. Very nice and improved. I completed the hill home. I picked up a couple MPH. The Throttle is always mashed so I know I’m feeding it the same throttle opening.  
 

This beauty Chrysler, and yours too, deserves your best.  I continue to get my Windsor closer and closer to feeling like a new car with each improvement and lesson that I learn.
 

Driving it these days, it feels like it floats and rides so smooth. Its wonderful and very rewarding. 
 

I’ll continue to find excuses to buy more tools for these old Mopars. Damn they are just fun cars. 
 

@Worden18 where did you hook the clamp to spark #1? To get the tach to work. Thx. 

Edited May 20, 2020 by keithb7

[Worden18]

51 minutes ago, keithb7 said:

Out for a cruise tonight  I notice a very smooth idle. Very nice and improved. I completed the hill home. I picked up a couple MPH. The Throttle is always mashed so I know I’m feeding it the same throttle opening.  
 

This beauty Chrysler, and yours too, deserves your best.  I continue to get my Windsor closer and closer to feeling like a new car with each improvement and lesson that I learn.
 

Driving it these days, it feels like it floats and rides so smooth. Its wonderful and very rewarding. 
 

I’ll continue to find excuses to buy more tools for these old Mopars. Damn they are just fun cars. 
 

@Worden18 where did you hook the clamp to spark #1? To get the tach to work. Thx. 

Around the wire Keith.  Anywhere where it will stay still when the car is running

[keithb7]

@Worden18 I assume the end of your wire,  for the spark plug, does not look like this?

This is my dwell wire clamp. 
 

 

[Worden18]

17 hours ago, keithb7 said:

Well, its not new, but it is new to me. I’ve never owned one before. The more old tools I buy to maintain these old cars, my life somehow gets simpler and happier. 
 

It must have probably been 1987 in grade 10 shop class, the last time I used a dwell meter.  I read somewhere that setting the gap with a feeler gauge  is fine for a brand new set of points. Then the first time you file them and set again, the feeler gap method becomes inaccurate. Each time you file it gets progressively worse. 
 

So an old Snap-On dwell meter was justified I figured. Spec for my ‘53 265 is 36-42 deg. I measured 27.  I filed, adjusted and fired it up. New reading 37. Gapped some more measured 40. Good to go! Riveting stuff. 
 

Next I checked the timing. It was out too. Spec 0 deg TDC. Now is back in spec. I also watched the timing advance as I blipped the throttle. Watching the vacuum advance it further. Higher rpm the centrifugal weights take over. Check. All good it seems. 
 

Next was the vacuum gauge. Rock steady at 20 at idle. I used the meter to adjust the idle air mixture screw. Out till the needle started to jump around. Back in till it jumped around. Found a happy middle ground. 
 

Test drive it seems very good. Smooth. Nice steady smooth idle. 
A very satisfying job in today’s digital world. 
 

I will email snap-on for proper literature. I can’t seem to get proper RPM readings. Something tells me I’ve not hooked something up properly to get RPM. 
 

 

In this picture, the 2 red clamps, the one with the square hole sitting under the handle of the timing light...that goes around the plug wire.  Unless it's part of that timing light of course.  My dwell meter has red and black leads for the battery, and that red clamp with the square hole for #1 plug.

[Sharps40]

"...So an old Snap-On dwell meter was justified I figured. Spec for my ‘53 265 is 36-42 deg. I measured 27.  I filed, adjusted and fired it up. New reading 37. Gapped some more measured 40. Good to go! Riveting stuff..."

 

 

Set the dwell small/low side of spec.  Itll grow to perfect then past max spec with driving maximizing life of the tune.  

 

(Inverse relationship- small dwell is big gap)

 

You can check the point gap but I just work from dwell and let gap fall where it may.  Just like choosing initial ignition timing, i set it all in at about  3000 to 3400 rpm w/o vacuum advance and if there is no ping on the test drive i know the initial timing is whatever the engine and dizzy need. 

Edited May 20, 2020 by Sharps40

[Sniper]

Good job, I still have my first dwell meter, bought it in the 80's.  Used it on the Cambridge this past fall, still works fine.

 

 

[Sam Buchanan]

All this dwelling on tach talk prompted to me to find my old dwell-tach from the VW days in the 70's. Here it is....bet I bought it from JC Whitney....isn't that where we got everything back then?  ?)

 

 

It still works to some degree...hooked the red lead to the positive battery post and the black one to the wire going to the distributor. I'm wondering if the tach is reading a bit high....dwell indicated 40* and that is probably pretty close.

 

 

Edited May 20, 2020 by Sam Buchanan

[plymouthcranbrook]

7 hours ago, Sam Buchanan said:

All this dwelling on tach talk prompted to me to find my old dwell-tach from the VW days in the 70's. Here it is....bet I bought it from JC Whitney....isn't that where we got everything back then?  ?)

 

 

It still works to some degree...hooked the red lead to the positive battery post and the black one to the wire going to the distributor. I'm wondering if the tach is reading a bit high....dwell indicated 40* and that is probably pretty close.

 

Shoot, I still get a couple of e-mails from old JC every day.

 

[westaus29]

I am in the same club as many of you. Most of the tuning gear has been in the cupboard for years, only ever use the timing light. Maybe I should pull out the dwell meter seeing as my hearing is no longer A1, at least that's what my chief assistant tells me.