Hot Rods coupe left me stranded need advice

Here's the details.

29' ford coupe with 59ab flatty rocking aluminum heads, dual 94 carbs, a Bubba electronic distributer, aluminum radiator.

Driving home from show yesterday and got about 10 miles from house and the car just died on the high way. It was a hot day, out side temp was around 91. Motor temp, right side 200 deg, left side 190 deg.

So I was cruisen down the highway around 65-70 mph. The engine stumbled, back fired and cut off. Luckely I was able to coast to the exit. Tried to crank again but seemed like no spark. I felt around the engine and started checking wires. Coil was hot, so father in law went and bought a new coil. Put it on and it fired up briefly but died right away. So we traced all wires and fuses and found nothing. So decided to put more gas in the car, put gas in and kept pushing the pedal and finally after about 15 tries it cranked. As long as I kept the pedal in it and rpms up it stayed running.

So decided to head home, made it about 300 yards and it died again. Pumped the pedal like crazy and finally cranked. ( blue smoke was coming out of exhaust, figured I was flooding it) this time I kept the pedal to the floor and was rolling down the highway. Cruised for about 2 miles and as soon as I let out of the pedal ( running around 100mph @ 4k rpm) due to a slow car in front of me it back fired and died. So again I coasted to an exit. This time I was not able to get it to fire, I had the fuel pressure set at 1lb so I turned it up to 2lb thinking I may be vapor locking. At this point in am lost. Any advise would be helpful.

Thanks

 

Have you checked the fuel filter it maybe plugged just enough that it won't let fuel through when its not under full pressure. The other thing is the ethonal fuel boils at a lower temp than the regular fuel causing vapor lock Just a thought Hobo Jim

 

first, did you check for spark? did you check to see if it is getting a good supply of fuel to the carb?

 

WOT but will not idle.....(new coil squirrel) Is it dumping fuel while trying to idle? possibly the power valve(s) is blown. (the backfire is a clue) or....the points closed up/carboned. Whenever I have a weird one like this I change the distributor condenser.

 

I have plenty of fuel at the carbs have pressure gauge at carbs. Been running 1lb now bumped up to 2lbs. I do have spark coming from dizzy to the coil ( shocked the heck out of me) I do have an electric fuel pump. It has a brand new coil I put on yesterday.

Tried cranking this morning, turns over great, show good fuel pressure, smell gas in the carbs. How can I check the power valve?

 

Your description of what happened is EXACTLY what happened to me last weekend except I have a 351 Ford SVO motor in my '39 Deluxe Coupe. After the initial incident, it would not run above idle, 800rpm. Limped back to town, coil was so hot that gloves were required. New coil fixed the problem. Possible your new coil is bad? Seems they are all Chinese made.

 

I am picking an initial electrical fault to cause the backfire, then blown power valves, the plugs got fouled also compounding the issue.
Now you are home slowly go through things and describe your voyage of discovery.

 

btt

 

Yea will do, my coil was crazy hot as well.The new coil may be bad as well. Other than swapping coils is there a way to test a coil?


What causes a power valve to blow? And how can I test that as well?

Thanks

 

Backfiring through the carburetor can damage the power valve(s). A telltale sign is a lot of fuel trickling in at idle.

 

OK silly question. Are you running on 6 volts or 12???

 

12v. The car will not even crank so it won't idle now

 

Won't crank as in the starter won't turn the engine over or as in it turns over with the starter but won't fire.
I you left the key on for a period of time while trying to sort the ignition out and it trys to crank but acts locked up I'd pull the plugs and see if it will crank over and possibly blow gas out of one of the cylinders.
If it doesn't try to crank at all start with charging the battery and checking the connections on the cables and work out from there.
If it cranks over but won't fire don't worry about the last two paragraphs.
There are coil testers that you can test a coil off the rig with. I've got one that is probably as old as I am but it works pretty well. You can check the primary and secondary windings with an ohm meter to see if if they are within specs but that might not catch one that breaks down when it gets hot.

Usually having the engine backfire can cause a power valve to fail but sometimes the diaphragm just ruptures in them.

 

Isn't 1 lb. psi on the fuel pump kind of low? I always thought 3-4 was best.
Anyhow, hope you get it fixed. Let us know.

 

It turns over just doesn't fire.

 

So you checked, and have no fire at the plugs?

 

Not had a lot of time to work on it but did put a new coil on, put new spark plugs gaped at .030. And still no luck. Still digging.

 

Is it a GM style HEI? The modules in those are notorious for crapping out. I had a couple of them do weird things to me, although they never completely failed. I'd just get stuck until the engine cooled off.

 

I'd start with a condenser.

 

It is a stock crab dizzy that I sent to Bubba where he converted it to an electronic dizzy.

I did some more checking and I am not getting any spark from the distributor. I held a screw driver and a spark plug in a spark plug wire and placed it close to a ground and got no spark? I checked the coil, clamper test light to ground and put test end on positive side of the coil and it lite up. Checked negative side of the coil when cranking and have power there. I pull the coil plug wire off the dizzy and try to crank and get.no spark either.


I have checked my reisitor and have power going thru it as well. I did spray starter fluid into the carb and car still would not crank. I plan on pulling the dizzy and giving Bubba a call tomorrow.

 

So I sent my distributor back to Bubba and the control module in the distributor had burned up. He mentioned this would happen if the Ignition was left on with the car off. The car died while going down the road and this is the second time this has happened. What else could cause this to happen??

 

As mentioned.....have you replaced the condenser?

I have a very similar setup as you but a dual point dizzy from Bubba. I've gone through 3 condensers already.

 

The distributor is a original converted to electronic by Bubbas Distributors. There is no condenser

 

Usually heat is the only thing that kills the module. I assume Bubba knows who is making good modules unless nobody is. There are different brands available but they might all be made in the same factory in China and just have different labels applied. Just carry one with and the tools to change it. Just 2 screws and some wires.

 

This is the best explanation I have ever found.
http://www.hotrodders.com/forum/gm-ignition-module-burnouts-38462.html#/topics/38462?_k=qjgisg

 

Did he recommend using dielectric grease under the module?

 

Just a thought BillyBob but I'm thinking we've had modules go "bad" after welding on the car. Muffler, shock mount, etc. Happened on two cars. Both with flatheads and electronic ignition. Most other things checked out and I'm guessing welding was the problem? Thereafter whenever welding, I make sure the battery was disconnected and unplugged the wires to the dist. Seemed not to cause a module problem.... Anyone have this experience???

 

My electronic module in my '40' Ford went out after the upholstery guy tried a quick start off of a battery charger. Car had been at the shop for awhile and battery had run down. Modules seem to be sensitive to leaving key on and surges from charging. I installed a new module and it has been running fine for the last couple of years.

 

Put points back in it.

 

^^^^what he said!^^^