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66’ 347 stroker stalled on highway. HELP

11K views 67 replies 24 participants last post by  pollock  
#1 ·
Hey everybody. I’m new to the classic Mustang world. I just bought a 66 with a 347 Stroker. The car has sat for several months with the previous owner who said he kept the fuel below a quarter tank. I put 6 gallons of 92 octane in it after I purchased it. The car ran ok at lower speeds and started backfiring a little at highway speeds especially when I gave it a bit more accelerator. After about 20 minutes of driving at highway speeds I hit traffic and it was stop and go. After 5 or so minutes of stop and go traffic it stalled. I was not able to fire it back up. Had it towed home and am curious as to where I should start my troubleshooting. Any help would be greatly appreciated.
 
#3 ·
If the PO kept the fuel below 1/4 tank it probably developed rust inside, and that has made its way to your fuel filter, carb, its small orifices and the power valve. Good luck!
 
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#7 · (Edited)
So when something like this happens I think the tendency is to believe that it's a fuel issue but it is sometimes a simple ignition issue. I've been down that road myself many times. In fact, I once replaced an entire carb to no avail. Then I replaced the sparkplugs as a last resort / shot in the dark and it fired right up. :LOL:

I've also had numerous vintage motorcycles with kill switches that inexplicably failed between rides. That's a real hair puller.

What's your ignition system like?

P.S. on a high performance engine like that a real coolant gauge would be prudent.
 
#8 ·
As above, determine if your missing fuel or spark before chasing guesses. Check for spark at the end of the plug wire. If no spark there check for spark at the coil wire next. A slowly failing ignition will give you the same symptoms you described as would a failing fuel system.
A plugged fuel system would have to be pretty bad to not start at all, but a failed fuel pump would certainly give you a no start.
Don't forget to keep telling yourself how much fun old cars are...
But at least you can likely fix it yourself!
 
#11 ·
UPDATE: I changed the in line filter and fresh fuel. Car started fine and ran fine. I let it idle for a few minutes (5-10) I revved it lightly once and it was fine I revved it a little more aggressively and it stalled again and will not start. It cranks but won’t start. There is fire.
 
#10 · (Edited)
My car had crud in the gas tank when I first got it. The fuel filter would clog at random times. I carried spare fuel filters and a vice grip. I learned how to change fuel filters very quickly. I did it several times in the middle of major LA freeways and boulevards. Once I stalled on Santa Monica Bl. without a spare filter. I took the clogged one out, blew it out backward with my mouth, reinstalled it and drove on.
 
#22 ·
Windsor and Cleveland pumps are of a different design with the bolts at 12 and 6 o'clock for the Cleveland and 3 and 9 o'clock for the Windsor.

Good to know that I can replace my pump to filter hard line with a longer one! I'm currently running an additional small fuel filter right before the one that screws into the carb, as you pictured above. Probably overkill? Thinking I'll order that new pump to carb hard line and eliminate it since it wasn't there from the factory. The less rubber lines the better.

Sorry for derailing this thread!
 
#24 ·
If you are running a MSD pro distributer there is an odd problem that can happen. It has happened to me a few times, and to other people I know.
It will not fire correctly without a constant minimum 9 volts.
So.
If your alternator stops working. Your car will run the battery low. The MSD will start to miss fire and then shut off once it cannot draw more than 9 volts.
Might be worth exploring. Just trying to help.
 
#25 ·
I appreciate all of the help. The PO did run rubber fuel line from the pump to the carb with an in-line filter before the carb. I bought the stainless steel fuel tube to correct that issue. I also bought a new distributor, new in-line fuel filter, ignition solenoid, and plug wires because I don’t like the other ones. Everything should be here Wednesday so Thursday I should be able to have it done. I honestly don’t think it’s fuel related. I think it’s ignition related because it wouldn’t idle nicely and stall when I tried to give it gas. I think one of my ignition components is getting hot and shorting. After I let it set for a while I can start it again.
 
#27 ·
Be careful of the starter solenoid. The cheap replacement solenoid is a known fire hazard. If you have an original starter solenoid, keep it on the car. If you bought a known name brand you should be ok. The cheap solenoids have contacts that arc closed while cranking and the starter keeps turning after starting. Unfortunately the only way to shut off the engine is to pull the coil wire.
 
#36 ·
#37 ·
I changed the plug wires, ignition solenoid, distributor condenser, and accelerator pump. Now the car will turn over but will not start. Positive the firing order is correct. The carb is getting fuel as well. Plugs?