Big mystery finally solved...and who deserves the prize?
 

About six weeks ago, I posted the thread “Who Can Solve This Mystery? Win a Prize?” Astoundingly, it was viewed more than 11,000 times and more than 200 of you wrote replies with suggestions to solve the problem that was causing my 29 CC P/U to intermittently sputter, backfire and fail to run more than about 6 mph. Sometimes it started up and ran just fine, most of the time it did not. You could never depend on it to get you there—and back.

First, thanks to all of you who pitched in with ideas. As I reported (and will discuss in detail below) several fellow club members spent many hours trying our best to follow all your suggestions, except Brent’s ideas to check for loose lugnuts on the left rear wheel and make sure the radiator coolant had the proper mixture…those were jokes, right?

After weeks of trying virtually everything, we were just never able to identify the real problem and resolve it. In sheer desperation, I finally turned it over to the fellow many of us call “The Guru” here in our local club in Jacksonville, FL. H.L. Chavin would call him a “Model A Whisperer” with the patience and know-how to sleuth out the problem.

I’m happy to report that it appears the mystery has finally been solved! And so what was it?

According to "The Whisperer": The grounding strap from the battery to the frame was not always providing sufficient ground to provide ample and consistent juice to the distributor. Sometimes it worked just fine—like on my long drive to coastal Georgia where the truck ran fine for 110 miles before it suddenly started acting up—and then other times you couldn’t even get the thing to start.

The local whispering guru says a continuity test with a meter confirmed this. (For the benefit of us all who have experienced a similar perplexing problem, he’s planning to write a more-detailed explanation later here in this same thread.)

So what about the prize I offered in my total frustration to find the answer? Who should get the prize?

Turns out, after scouring all the suggestions previously posted, it’s not so easy to select the winner. Without sending you back through 20 dozen postings, here are the people who got CLOSE to identifying the problem.

The g-word was actually first used in Post #4 by “Brent in 10-uh-C” who suggested checking for a blue spark from the coil wire to a ground source when the engine cranks. This didn’t resolve it because we GOT the spark when the ground strap was working okay and the engine was running as it should.

In Post #19, “Modelacoupe3” suggested a ground problem caused by the wire to the upper plate of the distributor. We changed that but no ground problem there. Eventually, we even dropped in an all-new distributor and still the engine didn’t run right.

Then, in Post #41, “Mike V,” a senior member from South Florida, wrote on January 27: “Grounding to the engine.” He went on to guess the fuel line was acting as an engine ground which was conducting heat to the extent it was causing the fuel to turn to vapor. Although he clearly mentioned grounding, we took it to be a contributing factor to "the real problem" which he believed to be the dreaded vapor lock. He suggested “place a cable from the chassis to the engine and see what happens.”

On the same day, “MikeK” from the Windy City offered a host of suggestions to ascertain whether root of the problem was fuel or electrical. In his paragraph on electrical, he wrote: “You may also experience that type of behavior if you are running on straight generator, with the connection to the battery lost.” He went to suggest: “Remove/clean- frame to ground strap bolt, both battery terminals, heavy cable to starter, wiring from cutout to starter switch, wiring to terminal box” and maybe, he suggested, there could even be a problem with internal connections between cells inside the battery. But since I long ago replaced the generator with an alternator, we didn’t think Mike’s hypothesis was valid in this case.

After 101 posts, “Mike V” in Florida, recalled and summarized many earlier suggestions and asked if those were followed, including. “Was the ground to the engine checked?” Mike was sure “We can get this!” We kept on looking.

24 posts later, H.L. Chavin hit on the ground problem again, but we all got a little sidetracked because his theory was presented in the context of bad grounding causing vapor lock as the real heart of my problem. H.L. said this could be checked by splicing a short piece of rubber hose into the fuel line, ostensibly to reduce heating the fuel in the line. We replaced the copper fuel line with a steel one but problem continued. A few posts later, he also asked “possible new painted engine blocking ground?” Nope, paint wasn’t my problem.

Later, H.L. did suggest adding a second ground strap (again as another possible step to resolve a vapor lock). Here again, I was sidetracked because the engine would often run just fine for a prolonged period. None of us could see how vapor lock that was caused by lack of ground (or anything else) could be my problem.

And then, on March 1 (Post #236), Rock Hornbuckle in Auburn, Washington jumped into the dispute about whether the coil needs a ground. It was in that context he suggested: “With an ohm meter, check the readings between the engine/frame, engine/coil should read open, engine/battery ground post, battery ground post/generator ground. If all the readings are the same, you don't have a grounding problem. Do these checks cold, then do the checks when the engine is hot and quits.”

Rock went on to sound a little like my college physics professor (gawd, I hated that class) but added an explanation of how this problem could have caused my problem to be so intermittent: “I know this sounds crazy, but electrical resistance in your engine block and wiring changes with temperature. If you have any bad wires (thinning through age) the slightest heat rise will affect its current carrying capabilities. The same holds true for any bad or loose or intermittent ground connections.”

The Whisperer here has taken the truck on a long drive to St. Augustine. He reports it ran just fine except for some brief sputtering which he says was crap in the fuel and once that was out, it resumed running as it should.

Hoping it is finally no longer possessed, I'm picking it up and taking it on a club tour event this coming Sunday. I'll report how it does on my test-drive! Meanwhile, watch for the more-technical details of what got me back on the road. I think it could be a big help to many.

Now, as to the prize:

Brent log ago suggested an ARC (Answer Review Committee). So what do y’all think? Who deserves the prize? And what should it be? How about the old ground strap that looks like it WAS the heart of my problem?

As always, suggestions warmly welcomed...and thanks again to all of you for your patience!

Re: Big mystery finally solved...and who deserves the prize?
 

If you think I won, I donate my prize back you. Just knowing what finally solved your problem is prize enough for me.

Re: Big mystery finally solved...and who deserves the prize?
 

Okay did I miss it ? What was the prize ???
Al

Re: Big mystery finally solved...and who deserves the prize?
 

A member of our club had a woven ground strap that looked pristine and had no continuity end to end. the copper had corroded under the crimp.

Re: Big mystery finally solved...and who deserves the prize?
 

Glad it's back to driving!!! Boy will I sleep tonight! Been awake for weeks thinking about this problem!!! Good Job All. And thanks for the report...

Re: Big mystery finally solved...and who deserves the prize?
 

Re: Big mystery finally solved...and who deserves the prize?
 

I didn't reply to the thread. I hope that the problem is solved, I've got my doubts. I've got to lean toward Brents idea that the mix could be wrong in the radiator. After all, Tom Wesenberg runs a 50/50 mix year round. Insert smiley face. Sorry, I just couldn't resist.

Re: Big mystery finally solved...and who deserves the prize?
 

sgwilson904, So glad you found the culprit....by the way, I did teach at the college level!

Re: Big mystery finally solved...and who deserves the prize?
 

Hi Steve,

In my sincere opinion, as a very refined gentleman, you already "shared" the prize among "all" of us, by:

1. First, reporting that it is finally fixed.

2. Showing all the way through, that you never gave up typing detailed messages & brought out tons of written Model A experiences from many others whereby we all witnessed that we still have many wonderful true Americans willing to assist.

3. You came back to share & write in detail exactly what was found. So many American One-Way-Street-Individuals today are so brain washed with Government hand-outs etc., that they no longer have the word "thanks" in their vocabulary.

4. How about this? After all of your efforts, devout appreciation, and kind words, maybe you should tell us what you need for your Model A & we can look to see if we can mail "you" a prize!

Re: Big mystery finally solved...and who deserves the prize?
 

Great idea, Mike, and I have just done so! Thanks again!

Re: Big mystery finally solved...and who deserves the prize?
 

Great thread, group participation, persistence and results. I think the offending ground strap should be mounted to a plaque and placed in the clubhouse or be presented to a member each year after a foolish blunder or an elusive problem like this one. What a great site!
Al Leach

Re: Big mystery finally solved...and who deserves the prize?
 

Re: Big mystery finally solved...and who deserves the prize?
 

seems to me that the "guru" gets the prize.
after all, assuming all is fixed, he's the one who got you back to where you should be......

Re: Big mystery finally solved...and who deserves the prize?
 

I think that we all won the prize by following your mystery and then finding out what the problem was. This may help any one of us who has a similar problem in the future. Thanks!

Re: Big mystery finally solved...and who deserves the prize?
 

I wouldn't be resting easy just yet.:confused:

So many different things were tried, and poor connections can come and go, but wouldn't your battery ground having a poor connection have shown itself as slow to crank or no crank at times? Since the starter draws 100+ amps, it takes the best connections to make sure it cranks normally, and I don't recall slow to crank ever being mentioned.:confused:

Re: Big mystery finally solved...and who deserves the prize?
 

the brief sputtering that was reported on the road test ,(crap in the fuel) has been playing in my mind. i hope it is fixed and the sputtering was nothing but it has me worried.

Re: Big mystery finally solved...and who deserves the prize?
 

Don't dare to speak it, Mitch, but I worry about that myself. Guru has already suggested getting carb completely rebuilt and he will have one handy on upcoming weekend day trip, just in case. My worry is that when we suspected the carb and replaced it earlier with one known to be good from another running car, the problem was NOT resolved, i.e. the working carb didn't solve sputtering/backfires, making us think fuel flow and carb were NOT the cause.

So, now that you're thinking along these lines, what are you thinking it MIGHT be that's still not fixed? What could be left?

Re: Big mystery finally solved...and who deserves the prize?
 

I feel Tom w made a good point. Is it cranking better than before since the high resistance was corrected

Re: Big mystery finally solved...and who deserves the prize?
 

Re: Big mystery finally solved...and who deserves the prize?
 

I also go along with Tom's idea. I think there is some other problem and my $.02 worth of comments would be that it is something electrical. But what is confusing about it being electrical is that an electrical problem would normally close the engine down, not let it sputter. So I am not of much help here except I don't think you have found the problem yet!

Re: Big mystery finally solved...and who deserves the prize?
 

You raise some interesting points but puh-leeeeze, say it ain't so! I guess I'll know soon enough if I take it south several miles this weekend.

As for the starter speed: I must say that I do sense the starter is turning much stronger and faster than it did before. I never thought--and none of the club guys did, either--that it was sooo slow as to be a problem at first.

I also notice that now the horn, which always would blow before, blows decidedly louder and stronger than it did.

Re: Big mystery finally solved...and who deserves the prize?
 

If it's truely cranking faster and a better horn, then that's a good sign. I'm not a fan of bare metal, like sanding the crossmember where the ground strap is mounted, but a star washer between the cable and frame should give a very good ground connection.

Once running, the coil can get voltage from the battery and/or the generator, and that's another reason I'm not sold on the poor ground solution.:confused:

Re: Big mystery finally solved...and who deserves the prize?
 

I hope you have the problem fixed, but I do not think so.

Re: Big mystery finally solved...and who deserves the prize?
 

30 miles yesterday around town. 20 miles today. No sign of any problem as yet...but the real test is tomorrow on the 110-mile RT club tour down past St. Augustine. Fingers crossed.

You know, George, you may well be right but I'm hoping not. Sort of reminds me of my dear old mother. Whenever I got dejected about something, she'd always take me aside and tell me, "You know, Son, things always seems the darkest just before it's pitch black!" God bless my mom! She's always quite the optimist, isn't she? :D:D:D

Next update: Sunday night.

Re: Big mystery finally solved...and who deserves the prize?
 

Steve,

Humble additional "electrical" opinion -- only in High Humidity Areas:

FWIW, I have heard this particular "electrical" story so many times from school trained mechanics, shade tree mechanics, car owners, etc., etc., "especially" along coastal areas where one experiences high humidity, e.g., with ferrous oxide & non-ferrous corrosion:

I. Problem:

1. Vintage engine just will not start; or,

2. Vintage engine runs, starts missing, almost dies, then runs again "intermittently".

II. The Normal Reported Cure:

A. Change points; or,

B. Change condenser; or,

C. Change coil; or,

D. Change a wire?

Then whoever changed whatever reports it was "definitely" either item A., B., C., or D., & the "bad" part was thrown away & a new part was provided.

Later a vintage engine whisperer comes along, smiles, & asks for the "bad" part, tests same, & shows that it functions perfectly!

What "actually" happened was that, (again in "high humidity" areas), enough corrosion set in on the wire connection(s) to intermittently obstruct the flow of electricity.

When the "bad" part was extracted & thrown away, the connections were cleaned, a new part was provided; hence, the flow of electricity resumed.

In my opinion, Tom & others have credible comments such as:

a) When the engine is running, one can "totally" disconnect the battery because the electrical flow is coming from the generator; &,

b) Something else "appears" to have cause intermittent engine operation.

I cannot remember how many times I have witnessed & heard of no-start situations on all types of vintage engines, vintage outboard motors, etc., etc., caused by either corroded points that had to be filed with a point file, or something like junction box connections that had to be cleaned after finding a slight green colored corrosion.

If your whisperer checked and/or cleaned "all" of your electrical connections, (if they appeared they needed cleaning), at the points, condenser, coil, amp-meter, ignition switch, & junction box, in addition to finding a "bad" ground wire, I think if I were you, I would feel "electrically" safe to drive to Fairbanks & back.

Had a guy contact me by private email a few years year ago from Oregon about his Model A -- started walking him through a sequence with starting to check volts at the battery -- he gave up half way -- had his Model A towed into town & spent $375.00 or so to clean a wire in the junction box.

I starting using & have had good results with "Kopr-Shield" anti-corrosion on all electrical connections.

Just another experience -- but if you move to an arid region, forget about rust & corrosion.

Hope this helps and best of luck tomorrow!

Re: Big mystery finally solved...and who deserves the prize?
 

H L Chauvin. Very good point about the humidity vs. corrosion. I would also add, these Model A's are being stored for months at a time. Some in unheated and or non humidity controlled areas, which can contribute to corrosion. I have always lived by the addage, ground everything, engine, frame, gen, body, etc. It's the only way to insure having a complete path for current flow. Then, clean those connections once a year as part of your annual maintenance, and use a product like what H.L. Chauvin suggested. "Kopr-Shield"

Re: Big mystery finally solved...and who deserves the prize?
 

Hi Rock,

Might add that the actual corossion of electrical connections occurs more in fall, winter, & spring than in the constant heat of the summer, e.g., when temperatures vary about 40 degrees or more in a 24 hour period whereby electrical metal connections can get cold at night.

Cold dry, or cold humid nights & warm humid days causes warm humid air to condense on cold metal.

Experiment: Go outside on a warm humid day with a hot cup of coffee & a glass of ice water with ice in it -- outside of coffee cup stays dry -- glass is dripping with condensation -- same principle.

Witenssed many construction workers from more arid regions temporarily relocate for work in humid areas -- they leave metal tools outside overnight -- next day wonder why they see so much rust.

This type of corrosion on electrical connections occurs far less in the very humid warmer areas in the Tropics because the metal connections do not get cold enough at night; hence far less condensation & corrosion on electrical connections.

Allt this may sound silly to some in more arid regions; however, sincerely hope this helps someone with a Model A stored in an unheated garage in a humid coastal area where it can get cold at night.

Re: Big mystery finally solved...and who deserves the prize?
 

Boy ..the model a is so simple its hard not to get mad over something like this that doesnt work .......and then have it be a ground

Re: Big mystery finally solved...and who deserves the prize?
 

Okay, friends, here's the latest on my Florida Pickup Truck Mystery:

112 miles today on a club tour event. Much, much better performance. Only twice did I experience a problem and both times much, much milder than ever before.

Once, after a sustained cruise at 45 for about 10 minutes, I slowed to go around a traffic circle and then, when powering back up on the straightaway, the engine began to hesitate, sputter and backfired a couple of times while it lost about 20% of the power it had been running at. I turned the choke rod a couple of times and although that helped, the problem persisted. Then, I pulled out the choke, waited for it to clear up and then pushed it back in. When it was running better after 2-3 minutes of cruise, I twisted the choke back in the direction where it had run well previously and it continued to run fine.

Then, once again after cruising for a while, it sputtered and this time corrected with a full turn of the choke rode, not need to pull out the choke. When it smoothed out, I turned it back...but then, less than two minutes later, I stopped to meet up with some other guys, turned off the ignition, and there was one incredibly loud backfire. Fortunately, we were all out of there before the SWAT team arrived and I experienced no further troubles.

So now, we're thinking the carburetor needs some attention, that there may be something in there that's clogging a jet. It certainly seems that perhaps a better (now double) ground has solved 90% of the trouble and hopefully after we overhaul the carb, it will ALL be solved?

Re: Big mystery finally solved...and who deserves the prize?
 

Fuel flow,leaky manifod gasket(s)??
Is there another carb avail to swap out , perhaps from someone on the tour??
Paul in CT

Re: Big mystery finally solved...and who deserves the prize?
 

Hi H.L.

True, condensation is much more visually noticed in colder temperatures, but ALL air will contain some percentage of humidity reguardless of it's ambient temperature. It is the temperature differential proportional to it's percentage of humidity content that causes dewpoint. I have designed (engineered) heating and air conditioning systems in various climates for many different types of buildings, and all of them have humidity factors in the thermodynamic equations. You do not need to physically see condensation for humidity to exist and do it's corrosive deeds. Therefor, no matter what climate you store an electrical system in, you must perform due diligence and annual maintenance. We had corrosive effects in S.Carolina, DaNang, Hawaii, Okinawa, and the desert of California.

Re: Big mystery finally solved...and who deserves the prize?
 

Sure sounds like typical ethanol garbage gas problems. My car does the same thing if I have 10% ethanol garbage in the gas and the temp is 70* or above. When I use the good gas, (which is almost all the time) I never have a problem. Ethanol gas boils in the carb and/or fuel line and causes the lean mixture you've described.

Re: Big mystery finally solved...and who deserves the prize?
 

Tom, I think you're on to something there. IYO Could the ethanol coupled with a weakened spark (from decreased current flow) be a contributing factor? Is it possible that this problem is from several factors culminating and disguising itself as a singular problem? Has anyone seen something like this before?

Re: Big mystery finally solved...and who deserves the prize?
 

Like I said before if the choke helps it is a gas flow problem. Probable not the carb, but I know every one wants to blame carb. Like Tom said it might be the crap gas. I would check the flow to the carb should be a big steady flow. Take the line off at the carb to check the flow. It is only going to get worse as the weather gets hotter.

Re: Big mystery finally solved...and who deserves the prize?
 

Without being there all we can do is guess and suggest.:confused:

Re: Big mystery finally solved...and who deserves the prize?
 

Would love to be with you for the "road tests" from Jax to St Aug and back.............
Paul in CT

Re: Big mystery finally solved...and who deserves the prize?
 

Has this car been on any long runs lately in warm weather to see if the problem is fixed for sure?:confused:

Re: Big mystery finally solved...and who deserves the prize?
 

maybe no news is good news in this case