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I'm overhauling the ignition system on my 54'

New: Points, Dist Cap, Rotor, Condensor, Plug wires, and Plugs

I was just planning on going down to NAPA to get all of it, but after doing a parts search on their website I came up with a few questions. They have distributor caps with aluminum contacts, and some w/ brass, I assume the brass is better, but didn't know if I needed it, or if it was worth the money. Mine has aluminum contacts on on it right now.
I remember seeing a thread about different spark plug wires, but after searching, I couldn't find it. Is there a particular type of spark plug wires that the old 235 likes? Also, they have about three different sets of points, all look the same, but are labeled standard, heavy duty, and vented. What's the difference?? Which do I need??

Thanks Guys!

The cap with the brass electrodes are best & worth the difference. Wire sets are all resister wires now. They will work fine. Vented points are good. I would use either the standard or vented. I would use extended tip spark plugs like R44s Or R45s.

what's the difference between the points? What make are those spark plug part numbers? Is there something wrong with using the original spark plugs specified?

Cap with brass electrodes are the best to use.

Spark plug wires with copper cores are the best.
I use 440 packard spark plug wire,purchased off of ebay.

Points,buy the highest quality points that Napa stocks.
Points with a year warranty is a plus.If the points are poorly made and burn up in a short time.You can exchange the points.

I have cheap points last two weeks,high dollar ones last 30 days.

Jimmy

Sorry. Those are AC part numbers. The extended tip plugs (suffix S) are an improvement over the original. They are for o-head valve vengines only. The others are OK. The R is for resister plugs. They cut RFI in your radio or any electronic device near where you are driving. Same with resister wires.

OK...last questions to be answered. what is the difference between vented, and standard contact points?

And should the parts guy be able to cross reference the AC44 or ACR44S to another manufacturer? Because AC is AC Delco. On Napa's website it brings up 2 different plugs, Champion, and Autolite. Both have the same basic spec's

Thread Size:14 mm
Hex Size:13/16"
Reach Length:3/8"

Are these the same as the original plugs? or is this the same as the new (supposedly better) extended tip plug. I'm guessing that the 3/8" dimension is what is changed between the original and the newer extended tip plugs.

Thanks Guys

I'd stick with AC spark plugs, others will work but not as well.

don stocker-

yeah, I understand...but there is no AC anymore. Does that mean I use AC Delco??? I've heard of guys getting old AC plugs over ebay, but I don't want to do that...

Bryan,

The AC Delco spark plugs are the replacement for the AC brand. You can use resistor plugs or resistor wires, but not both. The truck will run with both, but the combination will raise the firing voltage slightly and will reduce the spark current quite a bit, which will appear to result in short spark plug life. But there really won't be anything wrong with the spark plugs. If you don't have a radio in the truck, the metallic wires and standard (non-resistor) plugs will be fine, but your truck will cause noise in radios and television sets when you drive past them. But realistically, I don't think anyone will notice.

As for the points, ventilated points have a larger moving contact that has a hole in the center to provide air flow and cooling. That feature is supposed to make the points last longer, but I don't know how effective it is. The idea sounds good, though. Heavy duty points have larger contacts and maybe a wider breaker arm for better heat dissipation from the contacts. They are intended for vehicles that operate at low speeds, with a lot of engine idling. Heavy duty points will last somewhat longer, but they are not for high speed- no racing with them, because they will start bouncing and floating at high speed and will result in ignition misfires. But I'm sure you won't be driving your truck that fast. The standard points probably have the 'standard' size contacts, not ventilated, and maybe a narrower breaker arm than the heavy duty version. The ventilated points usually have a larger breaker arm because of the larger contact, but there isn't much difference there. For your application, I don't think there is a compelling advantage of one type over the others, although I seem to remember seeing ventilated points that erode and transfer metal more than non-ventilated types, but there are several variables there, so I would hesitate to advise against using them. NAPA points are good products.

I prefer the brass/bronze cap contacts, but aluminum is alright as well.

Harvester

Harvester-

Thanks!!! You always do a wonderful job at thoroughly answering questions!

I know that the truck has vented points on it now (I was wondering why it had a hole in the center), but I think I will go with the standard duty points. I know that the NAPA website didn't say if the plug wires were resistor wires or not (part # BEL700126) so I will have to investigate that a little more...

Oh by the way....I called a Chevy Dealership, and I'm pretty sure that the old AC #'s are now AC Delco #'s. From what I understand all that changes is you add "Delco"

I'm willing to accept corrections on that though!

Bryan,

I think I am mistaken with my earlier description of ventilated points: the fixed contact is the ventilated contact. The moving contact is still larger, so it matches the fixed side. Not that it matters much, but if you get a ventilated set, the earlier description might leave you with more questions.

Harvester

Bryan, about 99% of the guys here are running AC R45 plugs in their inliners. Any autoparts should be able to get them, I buy mine at any of the three Farm & Fleet stores in my area. Very common plug and still readily avalable and it's what you will get if you order plug from any of the vendors. 10,000 miles on the set that are in mine now and they burn a nice tan color, and my engine is an oil user to boot.
DG

All of the plug wires now are resistor wire. Actually they are required by law because of radio interference. I could notice the difference when the resistance wire came out almost 50 years ago. I still make my own spark plug wires out of Delco Packard 440 which is stranded wire. I also prefer non resistor plugs. These engines were designed before resistance wire and plugs came out. It is my opinion that they run better on what they were designed for. Non resistor AC 45 plugs appear quite regularly.

Ken,

Are resistor-type wires required by law for old vehicles? Is it illegal for a vendor to sell old style wires?

Bryan,

This type of wires/ends would have been used up to 1953. They may be resistor-core but I would guess they are solid core - call them, if it makes a difference to you.

In 1954, the solid-core wires would have been used but there would have been rubber covers at the spark plug ends.

Tim

Well guys, I got it all installed last night. It started up on the second try!!! I was hoping that it would run better though...

Here's what I've got on it:

New Cap w/ brass contacts
New wires (resistor I think... doesn't say on the box, but it's a nice set...I'm pretty sure that it has that funny graphite impregnated fiberglass core)
New Plugs - Champions, Gapped to .035", Resistors. I can't remember the #, ( I know it had an R an 8 a C...but it was shown as a match in the NAPA system)
New Rotor
New Points
New Condensor
New Battery & Cables

Dwell set at 34 degrees (a little high I know, but it drops to about 31 when I rev the engine...which concerns me a little)

Timed so that the ball is aligned with the pointer. Timing was done w/ vacuum line disconnected


For some reason I'm getting intermittent spark at all cylinders,(not just one in particular) This is the same condition I had before I replaced all this stuff, the only thing I haven't replaced is the coil...is that the culprit??

Someone mentioned not running resistor wires with resistor plugs...could that be the problem? I don't think this is the problem, because the new plugs are the same as the ones I took out, and the old wires were Packard 440's which are definately NOT resistor wires (I would have left them on, but they were in bad shape)

Help please!

Tim, solid wire is supposed to be for non highway use only such as farm tractors or race cars. So is ZDDP However there is a gray area as to using what was original equipment in an antique vehicle. And I am not sure who is supposed to enforce this. Probably the FCC. Of course they are supposed to police CB also. They don't have the money to shut down 1000 watt base stations, much less catch mobiles. I guess I am inconsiderate. If the guy parked beside me at a red light has a little static in his radio, I don't really care. Furthermore, the new radios have much better RF filtration and he probably isn't getting static like we did with the old tube type radios. I buy Packard 440 on eBay, but I would strongly suspect that wire replacement sets would have a disclaimer somewhere in the fine print that they are meant for off road or competition only. Of course some disclaimers are pretty generally disregarded.

Bryan, I doubt that a coil would do what you are describing. Have you checked your vacuum advance? Also have you checked your centrifugal advance. You can watch the vacuum advance working by seeing it turn the distributor when you rev it up a little. You can check the centrifugal advance by disconnecting the vacuum advance and then putting a timing light on it. The centrifugal advance should advance it as it gains speed. My personal opinion is that these things were built for solid wire, but they will run on carbon wire. I would not add a resistor plug to it. Also, I mess with GMC, not Chev, but I think the ignition is similar. I have taken new Champions out of a GMC that had erratic misses and replaced them with AC and that fixed it. NOS AC45 sell on eBay for about the same price as other plugs sell over the counter.

Let me clarify...

The intermittant spark condition is happening at idle (and may be happening when revved, I haven't checked though) This condition was discovered using a timing light w/ inductive hook-up attached to various spark plug wires.

Since the problem is happening at idle w/ vacuum line disconnected, I don't think the problem is related to either the vaccuum or mechanical advance (both were working before the system was disassembled)

Bryan,

Your spark plug wires are resistor type, and the R in the spark plug type number also indicates 'Resistor', and they sound like RJ-8. The wires probably have one of the designations TVRS (for television and radio supression), RS (for radio supression), TVI (television interference) or just 'Radio Supression' stamped on the wire, but your description fits resistor wires. Unless your primary ignition current is low, the combination of resistor wires and resistor plugs shouldn't cause you any trouble. But you don't need both, and since non-resistor plugs are easier to find than metallic wires, I would change the plugs.

Your dwell setting is fine, and the 3° change is not excessive, although a little high for your distributor. Most manufacturers specify a 3° dwell change as allowable. Some go higher, but for not your type of distributor.

A quick check on the primary ignition system is to measure voltages with the key on, points closed; measured to the battery ground post:

Battery: 6.3 or a little higher = full charge; 6.1 or 6.2 is fine.

Coil (+): Battery voltage, less a couple of tenths, but no lower than about three tenths less than battery + voltage.

Coil (-): Maximum of 0.2 volts (maybe 0.25).

Distributor connection: less than the coil (-) voltage; around 0.1 is good, or slightly higher is alright.

Points, wire connection side: No more than 0.1 volt.

Distributor case/ground: no measurable voltage.

If you find a slight voltage at the distributor ground, clean the battery ground cable connections. It won't hurt to clean both battery cable connections anyway.

If your old spark plug wires are useable, you can use those without concern. The legality of non-resistor spark plug wires (the last I paid attention to the matter) is that Congress has to declare a national emergency, then the FCC can get involved and impound vehicles that are radiating ignition system noise. That authority goes back so far in history when noise filtering and receiver sensitivity in radioes and televisions was fairly primative, that I don't think there is much concern any longer. But the authority remains. Modern radio and television receivers hardly get any disturbance from a lightning strokes, so I hardly think there is currently any legitimate concern from metallic spark plug wires. (If you use the metallic wires, keep the hood closed when you are driving and probably no one will know what kind of wires you have. More on that if you are interested.) Although there is identifyable interference from broken spark plug wires of either type.

Harvester

>>The intermittant spark condition is happening<< >>condition was discovered using a timing light w/ inductive hook-up attached to various spark plug wires.<<

That is the timing light, not an ignition problem.
Try positioning the pickup at a different location and see if the light is more consistant.

Harvester-

Thanks for the advice, I will try these tests. If all the voltages in the primary circuit test OK, I will try the AC 45's (which I think are availiable through a local chevy dealership) All the battery connections are clean enough to eat off...

I looked through the shop manual but couldn't find a procedure to test the coil...what values should I be getting there?

Richard-

I tried moving the inductive pickup around on the wires...even to different wires...all the same, it will spark a few times then off a few times, on, off, on, off... Although I still haven't completely ruled out the timing light as being faulty, since it's meant for a 12v system. I will also try connecting it to a 12v battery.

Thanks guys!!

If your powering your timing light from a 6v system and it's a 12v light it may fire but it probablly can't be counted on. They generally are designed witn a voltage regulator to operate between 10v to 16v.
A coil is about twenty bucks at Auto Zone tax inclulded. That is the best way to check if you have a bad coil. A resistance check only checks the continuity of the windings, they can be ok and still cause problems like arc over when they get hot. A bad coil can cause lots of odd problems especially when they are hot.
DG

Bryan,

I think the timing light idea is the answer to your intermittent flash that you are seeing. If you actually have an ignition problem, you should hear/feel a misfire each time the timing light 'misfires.'

I don't have the OEM specifications for your coil, although I can find them, but primary resistance is typically around 1.5 ohms between the two primary terminals; secondary resistance typically is in the range of 7000-10000 ohms, between either primary terminal and the center terminal. Secondary resistance varies quite a bit, but a typical standard D-R coil runs around 8500 ohms. There should be infinite resistance from any terminal to the coil case when measured with the ohmmeter set to the highest range. If the coil is actually at fault, you should have irregular misfires during acceleration. Without that, I would not replace the coil at this time. Original Delco-Remy coils are oil-filled and are pretty reliable, and if there is no evidence of oil leakage, I would keep the coil for now.

Delco-Remy made coils for a variety of applications, so if the resistances are outside the typical ranges, you may have a good coil from another application, so don't throw it away if you replace it. They made one for a limited application that uses a secondary connection to the case and with no connection between primary and secondary windings (not an HEI application). I doubt that you have one of those; it would burn your points up if you use it- it has about 1 ohm of primary resistance, around 10K ohms for secondary resistance and the originals were bright red in color.

Harvester

The engine has been stalling upon hard acceleration, but I'm about 75% sure that it's the accelerator pump. I looked down in the carb and yanked the throttle rod and saw no gas squirting in...

I'm with you harvester, I don't think it's the coil, I'm suspecting the timing light for right now....more to come

Sounds like you found your trouble.

Harvester