How to use a timing gun?

[MarcDeSoto]

I have one of those dirt cheap timing guns that flashes with every spark to the no. 1 cylinder.  It gives a very weak flash.  I also have a 12 volt timing gun from the 80s.  I saw in one of Keith's videos that he uses a small 12 volt battery to power his timing gun.  I'm wondering if I can just use a 12 volt battery charger to power my 12 volt timing gun?  

 

 

[Sam Buchanan]

That's what I did last time I used my timing light on the 6v P15--my old 12v shop battery finally died.

[soth122003]

If it is an old charger yes. New chargers need voltage from the battery to work.

 

Joe Lee

[Doug&Deb]

I bought a cheap riding lawnmower battery for my timing light. It’s small and light and works great.

[desoto1939]

I have a sear 12v timing light. I just reverse the connecter alligator clips to het it into the correct polarity to be used on my 39 Desoto.  i have been using this timing light for the past 35 years.  I get an appropriate amount of flash light to see the white mark on my timing dampener.

 

So yes a 12 volt timing light will work just fine. If the flash is a little faint then turn off any overhead lights in your garage or work area and you will be able to view the timing mark.

 

Rich Hartung 

[Sam Buchanan]

Yes.....working in the dark will be a great way for me to get the timing light into the fan...........    ?

 

I tried using my old light on 6v but the flash was too dim to be useful so out came the old 12v charger, it works fine with the light.

[kencombs]

Years ago I had a reverse issue.  My light was 6v, really ancient but great quality.  So I used a 6v lantern battery to run it.

 

In today's world, I think the correct number of 18650 cells in a home-made tubular holder would be perfect.   Rechargeable, but in timing use probably would need that only every 5 years or so.  And they don't discharge when not in use.

[LeRoy]

19 hours ago, desoto1939 said:

I have a sear 12v timing light. I just reverse the connecter alligator clips to het it into the correct polarity to be used on my 39 Desoto.  i have been using this timing light for the past 35 years.  I get an appropriate amount of flash light to see the white mark on my timing dampener.

 

So yes a 12 volt timing light will work just fine. If the flash is a little faint then turn off any overhead lights in your garage or work area and you will be able to view the timing mark.

 

Rich Hartung 

ditto all this at my place

[Bingster]

But how do you use it?  The flashes correspond to the white marking?  When they line up it's good? How to adjust till they do?

[desoto1939]

3 hours ago, Bingster said:

But how do you use it?  The flashes correspond to the white marking?  When they line up it's good? How to adjust till they do?

Bingster.  The engine has to be running at idle speed. But prior to starting the engine you will need to mark the appropriate timing mark on the lower pully. sand off the grud so you can see the timing lines then use use white paint to mark the appropriate line.  My 39 Desoto is set at 2 degrees before TDC or the zero line.

 

Connect the two alligator clips to the appropriate contacts. The car should be running smoothly and not at a fast idle. Pull the trigger on the gun and the light should blink.

 

I time my car off of number 6 sparkplug wire.  Point the gun with the bulb down towards the lower pully but be careful not to go to far as to hit the fan blades while they are turning.

 

Keep the trigger pulled and every time the light blinks it should light up the lower pulley and the white mark should be at the metal arrow or pointer on the front of the crankcase.  If the line and light do not match up then you need to time the engine to get it to run smoother.

 

This entails loosening the hold down bolt to the distributer with a 1/2 inch socket.

 

So but advancing or retarding the whole dizzy assembly the engine and timing will advance so the mark is at the pointed or retard the unit to get the mark and pointer to line up. It takes a small amt of turning the entire dizzy to accomplish this adjustment. If everything is fine then lock down the 1/2 bolt.  Test the dizzy and pull on the throttle linkage to make sure the car engine does not sputter and come back to the normal smooth running and recheck the timing with the gun.

[Bingster]

Hey, Thanks! It always seemed like some kind of a tricky thing to do but it seems pretty doable.