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How Do Bad Coils Act?


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#41 Fernando Mendes

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Posted 27 June 2010 - 01:46 PM

I already had ignition problem with my Jeep last year.I checked all this points, except the condenser.Talking with a friend he said to me "look out for condenser",it is more important!!!Begin replacing the condenser.After the rest.:)

#42 Dave72dt

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Posted 27 June 2010 - 02:00 PM

Yes, they were in the boxs of both sets I got.



I saw that tool on Tooltopia and thought about getting one, but I wondered how often I would use it and decided not to get it. Maybe some day I'll get one anyway.

Merle


I think long and hard about diagnostic tools, especially on these old vehicles. A test light, VOM, dwell-tach meter and timing light will get you a long way down the road with these basic engines. A timing light can test secondary wires well enough to know if they are working or not. Checking them at night or in a dark area will check for leakage or jumping and I can visually check polarity

#43 John-T-53

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Posted 05 January 2013 - 08:43 PM

I just got my newly rebuilt (for the 2nd time) engine running last week again, and have been tuning it hard core over the past few days.

It's running strong and drives great at all rpm's. Initially, it was a lil' rough running and had throttle problems, but the carburetors have been tinkered with several times and the setup is now synced up pretty good.

The slight miss was still there though. A timing light showed the miss on the pulley mark as it would skip a beat about every ten flashes. I was running an original auto lite coil, but had a new spare on hand so I switched 'em.
Now, a consistent flash on #1, however the mark moves around slightly, about two deg when running. BUT...at least this showed the old coil "skipping when it should be in attendance".

If I put the timing light inductor on the #6 wire, the timing is advanced about 4 degrees that that of #1, and there still a very slight miss evident in the tail pipe at idle. The dizzy has never been rebuilt, although points and coil have been maintained. The dwell is 39 deg at idle and moves down about 5 deg when accelerated. It might be time for a new dizzy, possibly a pertronix unit... Does this now sound like a dizzy problem?
- J.T.

1953 Dodge B-4-B 116

#44 HanksB3B

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Posted 05 January 2013 - 09:05 PM

Hi John,

I'd definitely carefully examine the wires inside the distributor, there could be a short. I have a good diagnostics guy (far from you) but if you can find a good mechanic up your way that is up to par with diagnostic machines with a first love for 50's vehicles, he may be able to see things the naked eye can't.

As far as your newly rebuilt engine goes "Long may you run"

Hank :)

Edited by HanksB3B, 06 January 2013 - 09:09 AM.


#45 Jeff Balazs

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Posted 06 January 2013 - 06:55 AM

Hi John;
It could be some play in the distributor itself but have you tried a different cap and rotor combination? I have run into very similar problems in the past which ended up being poorly made replacement parts. In the case of a certain model Delco distributor I found I had to fit OEM replacements manufactured by Delco......the others fit and looked the same but just didn't work nearly as well.
Hope this helps.
Jeff

#46 JBNeal

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Posted 06 January 2013 - 08:58 AM

A rebuilt engine will respond to optimum performance levels with a healthy ignition system and adequate fuel delivery. A faulty distributor can be repaired by a competent technician who is able to check all the variables in distributor performance. Distributors are prone to worn & out-of-adjustment points, condensor blow-outs, frozen or worn breaker plates, leaky vacuum advances, worn or out-of-balance mechanical advances, input shaft bearing wear, internal short circuits...I believe there are shop manuals that deal with the distributor/ignition coil combination alone because there are technical aspects that have to be addressed systematically to achieve proper function. The repair shops that advertise that they use a Sun Testing Machine to diagnose distributor issues get my attention as these pieces of equipment were used by mechanics back in the day to restore ignition performance. As distributors went to solid state components, these testing machines and the skill to use them became obsolete. Finding a shop that still has them and knows how to use them is an asset in owning a vintage beast :cool:

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#47 DJ194950

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Posted 06 January 2013 - 03:30 PM

No amount of (tune-up) will cure worn dist. bushings.
Dwell will ideally not change with rpm change.
Quick and easy dist. bushing check- remove cap. Push on the shaft side to side, point opening change = worn dist. bushings. Change of dwell will change the time coil has to soak up spark, also will change timing.

Just my 2 cents.:cool:

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#48 Don Coatney

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Posted 07 January 2013 - 07:11 AM

The repair shops that advertise that they use a Sun Testing Machine to diagnose distributor issues get my attention as these pieces of equipment were used by mechanics back in the day to restore ignition performance.



By using a power supply, electric drill motor, dwell meter, and a vacuum generator you can replicate all the functions of the Sun Distributor machine.


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#49 HanksB3B

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Posted 07 January 2013 - 09:53 AM

^^^Don, you never cease to amaze me^^^

Also (don't know who wrote it) found this in my distributor folder.

Distributor Rebuild

If you remove the points, condenser, and vacuum advance (pay attention to how it goes back together) you can then remove a couple of screws around the outside that hold the breaker plate in place. The breaker plate will then lift out and you'll have access to the advance weights. I wouldn't recommend disassembling any more than that. At this point you can clean things with solvent of brake clean as needed. Once it's all clean and dry drip a little oil at the pivot points on the advance weights and reassemble the rest. That's what I did with mine and it works fine.
That vacuum advance arm is that supposed to be a clip on the end holding it on the stud on the plate? Mine looks like a fine wire wrapped around the post. I'm gonna loose that I bet..
Yes, its a little wire clip. Be very careful when you remove it so that it doesn't go flying or you'll never see it again.

Distributor Position

Verified that the distributor is not 180' off by rotating the engine with my finger over the #1 spark plug hole until I could feel the compression stroke. Also double checked the placement and sequence of the spark plug cables in the distributor cap.

I mark the location of the rotor and also the location of the body of the distributor to a specific point on the block. I mark with a piece of chalk for the dizzy and also a piece of black tape (also the same for the rotor).

Disconnect the wire from the coil and also the vacuum advance line. Loosen the bolt that hold the distributor and pull the unit up and out of the block.

When you bench test for the gapping, set the rotor to the correct marking and then install the distributor and align it up to the mark you made on the block. Tighten the bolt a little but not fully. Start the car and then use the timing light to adjust the timing to the timing mark on the lower pulley. You can use a 12volt timing light,(just reverse the leads). The light will be a little weaker so do the timing when the lights are off in the garage so you can see the timing mark. Move the distributor either right or left to advance or retard the timing until you get the timing light firing when the timing mark aligns with the pointer on the block.

I always like to install a new breaker plate assembly since everything is then already connected. Keep your old plate and then rebuild with the new internal parts. Grease the small ball bearing the make the two plates rotate

The fastener at 7 o’clock id the distributor hold down as well as the timing adjustment clamp. Removing that screw will allow the dist to be pulled out of the engine assuming the wire and vacuum advance have been removed. You don't need to align the engine to tdc number one to pull the dist. just mark the location of the vacuum advance to the block and the rotor position. As long as you do not rotate the engine with e dist out, you will not have a problem reinserting the dist. The dist is driven by the oil pump, with a tang onthe ed of the shaft that look like a screw driver. I will go in either correctly or 180 off. so even if you do crank the engine you still have a 50/0 chance of getting it correct when going back in.

It is actually much easier to service the distributor with it out of the block.

The bare wire that you show, as long as it is not contacting any other metal parts in the dist should be OK. There were three of four (maybe more) different distributors used on MOPAR flat 6 engine. Assuming you have a 23 inch long engine, they all interchange. However their parts do not. There is a metal tag on the dist with a number on it. The replacement parts should be ordered by referencing that number.

With the dist out, you can check the unit for wear, clean it up lubricae it and replace the points and adjust them much easier than when in the vehicle. It will also keep you from dropping and loosing the small screws down into the body of the dist.

So take a piece of chalk or tire crayon and mark the vacuum chambers position to the block and the rotors position to the edge of the body and pull it out and give it a good inspection, cleaning and new set of tune up parts (rotor cap, points and condenser). Examine the shaft to see how much wiggle you have in the bushings. You can also check the vacuum advance to make sure the diaphragm holds vacuum. either by sucking on it out using a vacuum pump to assure it holds vacuum and moves the breaker plate smoothly.



Hank :)

Edited by HanksB3B, 07 January 2013 - 10:24 AM.


#50 John-T-53

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Posted 07 January 2013 - 11:19 AM

Confirmed...the shaft is a little loose in the distrubutor body, and I witnessed the point gap move as the shaft was rocked side to side.:o

Anybody ever rebuild their dizzy with new bushings? I couldn't find any threads where this was covered in detail (as you know I like to revive old threads)...however sending it out to a shop that rebuilds them has been discussed.
I'd at least like to find where new bushings could be sourced. After pressing them in, I'd imagine they would need to be honed to fit the shaft perfectly, probably with less than half thou' clearance.

Thanks,
- J.T.

1953 Dodge B-4-B 116

#51 DJ194950

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Posted 07 January 2013 - 04:23 PM

Seems that after some searching that Desotodav and Tod Finch have spent some time looking for #'s for the replacement bushings and came up with a Napa # ech 4070. There may be a diff. upper bushing # mopar 871752 but my parts book show that # as Export # only.

A search on Eichlin parts books shows #4070 to fit all mopar dist.'s to 1982.

During this search it seems that #4070 may fit mopar generators also. Front/back/both i'm not sure- spent no time on that subject! Lenght on bushing may be only issue between #'s.:confused:

Maybe a local starter/generator rebuildter may be able to replace/fit your replacement bushings.

Napa-eichlin 4070 were avail. in my local store which now has almost nothing for flat head mopars, which i think is because of the multiple uses.

Best to ya,
Doug

Edited by DJ194950, 07 January 2013 - 04:42 PM.

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#52 John-T-53

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Posted 08 January 2013 - 09:42 AM

Thanks...I didn't find 4070 but came up with # ECH 4270 at the local NAPA.

Bushings are on order, they are coming out of a warehouse in MN!
- J.T.

1953 Dodge B-4-B 116

#53 ggdad1951

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Posted 08 January 2013 - 10:02 AM

Thanks...I didn't find 4070 but came up with # ECH 4270 at the local NAPA.

Bushings are on order, they are coming out of a warehouse in MN!


See MN IS COOL! :P

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#54 Young Ed

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Posted 08 January 2013 - 10:28 AM

Thanks...I didn't find 4070 but came up with # ECH 4270 at the local NAPA.

Bushings are on order, they are coming out of a warehouse in MN!


See MN IS COOL! :P


Dang Mark I know where that warehouse is. We should have gone and bought them out and jacked up the price!
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#55 ggdad1951

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Posted 08 January 2013 - 10:33 AM

Dang Mark I know where that warehouse is. We should have gone and bought them out and jacked up the price!


Ed...SHHHHHH....don't let everyone in on our nefarious ideas! :eek:

;)

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