Distributor Cap

[MiamiSprite]

Was trying to adjust Distributor timing and got shocked, twice. Not sure if wires or cap are bad but figured will change both.

Based on my limited knowledge, my 1962 Sprite should have a DM2P4. Will side entry cap for 25D4 fit/work?

 

[DrEntropy]

Should do. The index tab may be in a slightly different spot so doing the timing will sort it. R&R the rotor too... and static timing it would be a good initial step.


What pat of Miami are you in (just curious, have friends and in-laws all over that area)?

 

[dklawson]

According to Jeff at Advanced Distributors, the same cap should fit the DM2, 23D4 and 25D4.
https://advanceddistributors.mybisi.com/product/side-entry-mga-distributor-cap-w-brass-contacts

 

[Guest]

Have a neighbor come over and check the dizzy to see if it's tight while you run it.

 

[MiamiSprite]

Thanks for reply. It seems that the more I try to make the car run better, the worse it runs. Is it normal to get shocked while rotating distributor?

Speaking of curious, I noticed you have text Great Pumpkin in your post. I purchased my car from Michigan and it had Little Pumpkin scribed in organge on the radiator. Any connection with spridgets?

I live in Palmetto Bay, which is just off of US-1 and 152 street in Miami-Dade County. As a point of reference, I always say East of Miami-Dade Metro Zoo.

Thanks to All for replies!

 

[JPSmit]

welcome! the shock would have been the capacitor.

and no - no pumpkin connection

 

[dklawson]

If your dizzy cap is cracked or carbon tracked it will allow high voltage to flow all over the surface. That voltage will give you a painful shock. One method of checking for high-tension problems is to wait until dark and start the engine watching for a light show on the dizzy cap and wires. However... getting shocked is another test method.

 

[MiamiSprite]

Getting shocked twice was enough, think I'll try the light-show tomorrow night. We’re having severe weather so can’t open garage door.

One thing I did not try earlier was to simply pull each plug individually while engine was running. Cylinders 1, 3 & 4 had the response I was expecting, engine nearly stops running and rough idle. Cylinder 2 had no change when plug wire was pulled. I checked plug and it had no oil fouling and gap was correct. I did not check valves, but I guess I should just to be sure they are not stuck.

I then proceeded to check wires with multi-meter but could not measure resistance in any wire (maybe bad multi-meter). I loosened #2 wire from cap and inspected wire. Did not see an actual wire inside cable. Trimmed end back ~ ¼” and still nothing. Is wire so thin its hard to notice?

I recall checking for spark on my lawnmower by removing plug, grounding it, and puling start cord. Can I use this technique and should I pull other wires so car does not start (or do it with car running)?

 

[Billm]

If you have a Harbor Freight nearby they sell a little gizmo that plugs in-line between the plug and the wire and lights up if there is proper electricity flowing. Try it on plug #2 to see if the spark is good.
BillM

 

[MiamiSprite]

Have one (HF) nearby and checked online for gizmo (Inline Ignition Spark Checker, $4.95). Going to pick one up today.

thanks!

 

[dklawson]

There are several different types of plug wire available. The most common two are solid core where actual wire filaments are inside. The second type is resistive and the conductor is typically carbon fiber. I think it would be obvious if you had solid core wire so the plug wires were probably supposed to be resistive. If the plug wire for #2 has totally failed, it could be that the shock you got came from that position on the cap since the voltage couldn't find its way to the plug.

Keep in mind that with resistor spark plugs you use solid core wire. With resistive wire you use "regular" non-resistive plugs.

 

[nomad]

If you do not touch the body of the car and are wearing rubber soled shoe's you should(???) be able to avoid shocks. Simply removing the plug, fitting it onto the high tension lead and laying it against the block while you crank the engine over should tell you if you have spark. While you are at it you can get a pretty good idea of the compression in the offending cylinder.
Kurt.

 

[MiamiSprite]

Best $3.99 I have spent in a long time. This thing really works! I actually purchased two (2) figuring it might be difficult to notice a difference and being able to test side-by-side would be definitive. Didn’t need two (2). It was clear, cylinder 2 barely lit the bulb while 1, 3 & 4 displayed a very bright light. I‘m assuming it’s the wire or cap and not something much worse. I ordered a wire set, cap and rotor so I should be able to see a difference next week.

I hope to add a positive follow up post next week.

Thanks to all!

 

[jlaird]

Solved that prob you did, now how about a part number on that tester.

 

[MiamiSprite]

It's #4424 for inline and # 4445 for 90 deg. I got one of each not knowing what to expect. The web shows them as $5.99 reg and $4.99 on special. I paid $3.99 each at store.

https://www.harborfreight.com/inline-ignition-spark-checker-4424.html


Definitely worth having!

 

[livinginthepast]

Keep in mind that with resistor spark plugs you use solid core wire. With resistive wire you use "regular" non-resistive plugs.

I had no idea. Guess I'd better figure out exactly what I'm running!

 

[jlaird]

thanks

 

[MiamiSprite]

Happy to report that the new wires solved the problem and the sprite is running great (on 4 cylinders). BTW, the side entry 25D4 cap is a perfect fit for DM2P4 distributor.

Thanks to all for help!

 

[DrEntropy]

:thumbsup: