1968 327/350, fuel or electrical issue

[Gary J.]

I am the third owner of an original 46,000 mile, 327, 350hp, 1968 convertible transistor ignition Quadra jet four barrel motor has not been apart, Air Injection Reactor and all stock. This car has been having problems since before I purchased it. No one has been able to determine, including me, If the problem is electrical or carburetor/ todays gas.
The Problem: The car runs fine when you called after a short period of time it begins to stumble when you come to a traffic light sometimes able to keep it running sometimes not. When you arrive at your destination turn off the car immediately try to start it Car turnover fine, but will not fire. Car cool down for. Time turns over starts up.

INITIAL Diagnosis not. Buy me…. Please fuel is causing the fuel to boil when it gets hot not allowing it to start. Second owner of the car temporary power back to standard points. Ignition with points ignition coil wiring distributor And replacement carburetor, problem, continued until I bought it.

SINCE I HAVE OWNED :
Return car, transistor, ignition powered, Original TI distributor rehabbed by famous Midwestern, T.i. specialist at a high cost, Return Coil to TI original 272 and tested coil fine. Replaced TI ignition box and wiring. Left on replacement carburetor condition continued.

RECENTLY:
sent out original carburetor numbers matching to be rebuilt at again of very high cost came back beautiful on the outside and hoped that it ran half as good as it looks. Took the car for a ride ran better than ever slower p.m. high rpm fantastic. Quarter-mile from home stopped at a stop sign car gradually Lost all idle and died. Push the car to the side of the road. Try to start saying no start condition. We did a period of time car started was able to get it home after changing the carburetor to the original non-matching numbers carburetor.

Beginning to think it’s not a fuel issue, in my opinion, it appears it’s something electrical. Once the car gets hot decided does not want to get power to the ignition to start. Operator removed has plenty of gas inside of it. Don’t believe that that might be the issue leaning towards electrical issue at this time.

SUGGESTIONS, PLEASE.
I apologize for the length of this post however, I wanted to include all pertinent data for those much smarter than me.
thank you in Advance
Gary

[Brian M.]

Gary,
I had a similar problem when I first bought my 65 L79. Turned out to be the coil. I installed one of NAPAs finest and the problem went away.
Brian

[Gary J.]

Brian,
Thank you ill try another coil.

[Michael L.]

During the restoration of my 69 I had a terrible time getting my car to run and it turned out the distributor wire was bad. Not fully broken so it would run but only poorly. It took like six months and countless hours of troubleshooting to figure that out.

Another thing was that I neglected to install the plate that goes under the Q-jet carb in the 69’s (not sure about the 68’s). Since it sounds like your carb has been off a couple of times I would check and make sure that that’s installed.

[Patrick H.]

Brian,
Thank you ill try another coil.

If you're trying a reproduction TI coil they are famous for not working well.
Should you be able to find someone with a real one you can borrow, I'd try that.

It does "sound like" coil, but it seems that 2-3 different coils have been tried without improvement, correct?

Have you checked the ground wire from battery to frame, and from engine to frame at the right engine mount?
Battery connections?

[Richard M.]

Gary,

I'm a bit confused with your statement.....

"Operator removed has plenty of gas inside of it."

When it stalls hot, did you remove the air cleaner and see if fuel shoots from the accelerator pump when activated by hand.

The result would tell you if it's fuel or ignition.

If no fuel, it could be a vapor lock issue.

Rich

[Gary J.]

Thank you all for your replies, when i try to start when it dies in hot condition i can see literal gas vapors rising from the carb as i turn it over. When i removed the carb and install non orginal carb car starts, about 20 minutes passed. The carb removed when tilted after removal had plenty of gas in it.

[Dave S.]

Seems your car calls for a 272 ignition coil. First thing to check would be to see if your 272 coil is an original Delco Remy or a reproduction. Reproduction coils are known to be problematic at best. If it is a reproduction it likely is your problem.

[Gary J.]

It is an original # 272 coil.
thx Dave

[Richard M.]

Ok, I guess autocorrect changed "carburetor" to

"Operator...." lol

So Dave brings up a good point. But even original coils could fail hot, albeit not many.

I'd try a NAPA IC12/UC12 Coil temporarily tie-wrapped in there. It will work fine on a TI Ignition for tests below max RPM.

[Dave S.]

It is an original # 272 coil.
thx Dave

As Rich says original coils can fail. When they do it can create intermittent behavior. If you could borrow an ORIGINAL Delco 207 that would put the possible coil issue to bed.

[Patrick H.]

As Rich says original coils can fail. When they do it can create intermittent behavior. If you could borrow an ORIGINAL Delco 207 that would put the possible coil issue to bed.

Best yet, an original known to work.

However, if the non-TI setup with non-TI coil had the same issue, the odds of it being the coil seem small.
As noted in my previous reply, I'd look at other electrical issues as well.

[Gary J.]

Thank you Patrick and all others for your suggestions. Tomorrow i plan to put the ca4 on race ramps and start at the pink wire from the starter and examine all i can see. I feel that if a wire is frayed or the insulation is thin near the starter would be the best chance to find such a situation. All that heat. If i am u able to locate any wires that need attention ill swap out for that that Napa coil that has been mentioned , i actually have one. I dont want to change too many things at once for fear of not identifying the actual problem.
i dont want to chase changing parts but want to find the cause.

thanks again,
Gary

[Richard M.]

Gary,

Did it fail the same with a points distributor before? If so, what coil was installed?

[Gary J.]

Richard
Yes it did fail when Hot with the pounts distributor , external ballast resistor coil 1303, # 0317.

was on the car wheni purchased it.
Gary