Engine shuts off

[John K Nelson]

Problem started this spring. Mostly low rpm driving or at idle. Once it shut off with 13+ VDC at 1100 rpm fast idle at start-up. Once in water box at race track. Don't recall if it was at 4000 rpm tire cleaning or when I lifted to idle up to the tree.
64 Plymouth; built in 2010; new wiring harnesses; MSD6AL; battery in trunk; Powermaster 160 amp alternator; smallest pulley allowed by PM for highest charging rate at low rpm.
I have replaced: 1. the ignition coil and moved it away from the engine. 2. Cap and rotor. 3. magnetic pick up in the P369071 distributor. 4. Battery.
New ignition switch on order.
Charging system issue?
Bad ground somewhere?

 

[RJRENTON]

Problem started this spring. Mostly low rpm driving or at idle. Once it shut off with 13+ VDC at 1100 rpm fast idle at start-up. Once in water box at race track. Don't recall if it was at 4000 rpm tire cleaning or when I lifted to idle up to the tree.
64 Plymouth; built in 2010; new wiring harnesses; MSD6AL; battery in trunk; Powermaster 160 amp alternator; smallest pulley allowed by PM for highest charging rate at low rpm.
I have replaced: 1. the ignition coil and moved it away from the engine. 2. Cap and rotor. 3. magnetic pick up in the P369071 distributor. 4. Battery.
New ignition switch on order.
Charging system issue?
Bad ground somewhere?

Is the coil grounded to the engine or the battery negative. You mentioned the smallest pulley allowed by PM...not sure what that means....which sheave....on the alternator or crankshaft.?? USUALLY the alternator is driven at 3-4 times faster than crankshaft RPM. I could clumb back on my soap box and say a lot if disparaging comments about MSD ignition systems.....but....not to elicit the rage of the MSDers...i'll refrain. I still use the old Prestolite dual point distributor in my GTX with great results. Just my opinion of course.
BOB RENTON

 

[Dennis H]

Changed my ignition switch. Made no difference. Bulkhead. Engine temp when this happens?

 

[John K Nelson]

Is the coil grounded to the engine or the battery negative. You mentioned the smallest pulley allowed by PM...not sure what that means....which sheave....on the alternator or crankshaft.?? USUALLY the alternator is driven at 3-4 times faster than crankshaft RPM. I could clumb back on my soap box and say a lot if disparaging comments about MSD ignition systems.....but....not to elicit the rage of the MSDers...i'll refrain. I still use the old Prestolite dual point distributor in my GTX with great results. Just my opinion of course.
BOB RENTON

Coil is mounted on fender to get it away from death valley between the heads.
Alternator pulley.
New ignition switch. Died again in traffic. Restarts in 3 - 5 minutes.
Tested charging circuit at battery:
No load, engine off 12.2vdc
1500 rpm fast idle start up 14.4vdc
800 rpm after warm up 14.2vdc
600 rpm in drive 727 auto 13.3vdc
This tells me the alt & volt reg are OK.
I have an appointment to have a speed shop check MSD/ ignition & charging circuits with o-scope diagnostics.

 

[John K Nelson]

Coil is mounted on fender to get it away from death valley between the heads.
Alternator pulley.
New ignition switch. Died again in traffic. Restarts in 3 - 5 minutes.
Tested charging circuit at battery:
No load, engine off 12.2vdc
1500 rpm fast idle start up 14.4vdc
800 rpm after warm up 14.2vdc
600 rpm in drive 727 auto 13.3vdc
This tells me the alt & volt reg are OK.
I have an appointment to have a speed shop check MSD/ ignition & charging circuits with o-scope diagnostics.

 

[threewood]

Sounds like an intermittent loose connection somewhere. Go over the wiring and connectors well.