8BA compression issues

[JSeery]

Originally Posted by mrlaser

Well the first two coils that I had tried tested 4.2 and 3.7 ohms when the multi-meter leads were placed on the pos and neg terminals. When the secondary circuit was tested they had readings of 9.14 and 8.39 K ohms. The NOS NAPA 6 volt, Echlin coil that I installed today had readings of 1.5 ohms on the primary circuit and 9.53 K ohms on the secondary. While I don't pretend to know much about this situation, I do know that the spark was much stronger with this latest coil.
As far as condensers are concerned, I have tried 3 different ones but currently have a genuine FoMoCo one in place with a Motorcraft set of points. The other condensers are of unknown origin.

I'm hoping there's a light at the end of the tunnel and that it's not a train

If you checked the first two coils correctly that would sure present a problem! Looks like your on the right track now. Never know what you have until you check.

[mrlaser]

I have checked both of the original coils with two multimeter. They gave similar results. The attached picture is with the inexpensive meter because it has a flat bottom. I needed that feature to free up mu hands to take the photo.

[JSeery]

Originally Posted by mrlaser

I have checked both of the original coils with two multimeter. They gave similar results. The attached picture is with the inexpensive meter because it has a flat bottom. I needed that feature to free up mu hands to take the photo.

Yep, that is not going to work well with a 6v system!

If your interested in the math, Voltage/Resistance = Current (V/R=I). In general terms you want around 4.0 amps at the points. So, at 6.0 volts and 1.5 Ohms resistance the Current would be around 4.0 amps. With the 3.5 Ohm coil it would be 6.0v/3.5 Ohms = 1.71 Amps which would result is a very weak spark.

The ignition system is somewhat more involved that this, but this should give you the general idea.

[mrlaser]

" Yep, that is not going to work well with a 6 v system"

EURIKA !!!

After months of wondering whether the engine would ever start, the thing fired up beautifully this morning. It turned out that the weak spark was due to a (2 actually) coil that I had purchased from a major early Ford supplier. When tested with a multi-meter across the positive and neg terminals they both measured 3.5 ohms. The 3rd coil, which was a NAPA, Echlin ,USA made product measured 1.5 ohms. This , unbeknownst to me , was the proper ohm reading. Anyway, I am pleased and relieved that things are now where they are. I appreciate the time everyone took to help me with this problem. Thank you.

[Bored&Stroked]

Glad you have it up and running . . . and I bet you learned a lot in the process. After all the time, effort and money - there is nothing like hearing it start for the first time! Now go drive it hard and get those rings to seat! Good luck and report back . . .

[Black Fifty]

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Good for you, Mr Laser! Fantastic news. I have been following along on your epic adventure. You should feel very good about your success.
Mike

[mrlaser]

Thanks. I have certainly learned a lot from the forum members. At times i felt rather discouraged, but took heart from the encouragement offered here. I also realize that others may be experiencing similar issues and benefit from the wealth of information supplied on this site. This is particularly true as fewer and fewer local mechanics familiar with the flathead engine are available locally.

B&S;

I will avoid running without varying loads. This, in spite of an overwhelming urge to "hear it one more time"

[Phil Gillespie]

A postive result where an actual faulty item was found, replaced with correct item and good result. logic progression and accurate fault finding.
beats the change out of several items at one time and crossing fingers and hoping for the best!
phil NZ

[Sid]

The parts man was probably thinking you were dealing with a 12 volt non resistor points ignition. That coil may be okay on 12 volt system. Just will not work with a 6 volt points type ignition.

[Roger W Gerow]

Re #12 above. Before any removal of parts I would try squirting regular motor oil in the cylinders first.-

[mrlaser]

I did do that very early on. It didn't result in an ignition. I actually did later squirt some assembly lube in each cylinder to temporarily boost compression.

[mrlaser]

The catolog image.

[Sid]

It just goes to show you that many of the parts suppliers and salesmen have no clue what they are selling. And if you ask them have they had any issues they play stupid and say they haven't. Just like JSeery stated earlier I don't think your car stood a chance of starting being a 6 volt with a 3.5 ohm coil.. If by chance it did start you wouldn't be happy with how it ran.

[mrlaser]

Actually, after going through some recent receipts, I found that one of the two coils with the high ohms reading (4.2 ohms in this case) came from a different supplier. After checking their website today, a 6 volt coil no longer appears when this part is searched for on the site.

[Bored&Stroked]

I'd surely talk to that supplier and inform them of the 'drama' that this whole wrong coil situation has caused you. They should at least take the coil back . . .

[Sid]

They should take back but we know they won't. It's electrical and been installed. What I can't understand is how someone can package a 4.2 ohm coil or even a 3.7 coil and say for a 6 volt system. You take it for granted that the manufacture and parts supplier have a clue of what they are selling. Also somewhere on the package the ohm rating should be shown. OHM rating is the most important thing to consider on coils especially with so many ignition systems available today and they all have the ohm preference they require. It was much easier 50 years ago when you basically had 1.5 ohm coils and 3.0 coils.

[mrlaser]

My main interest is to try to help others who may be experiencing similar issues. I'm still just ( kid in a candy store) happy that the problem has been solved. There were no specifications on the box or included in the box with the coil. The picture is of the top of the box. I did search the "B-12000 and found these coils in other supplier's catalogs. Incidentally, I did not purchase either coil from this source.

[Sid]

Sad part is that you could let these vendors know of your findings and they will still market these as a replacement early Ford coil and never research. Like you are talking to deaf ears or an illiterate. In the end it is the consumer that gets screwed. I've been there. If the car had happen to start it would not have run or start well and who knows how much you would have spent to find the problem especially with two wrong coils that you believed to be brand new and correct. It seems like quality and customer service are a thing of the past.

[JSeery]

When things come from China (the cheap stuff) there is no telling what you get. That is why you need to check. The other lesson is consider the suppliers you are purchasing this stuff from! Many of them are just in it to push parts and could care very little about quality or customer service. We have no one to blame except ourselves, there are venders who do care about quality AND customer service. A number of members here on the Barn provide quality parts, knowledge and service and are willing to help. When we learn to support those who care about the hobby this will stop.