1972 350 Surging Under Load When Stopped and at Operating Temperature

make sure your points are closed when checking for car not running

 

This dawned on me, too.. is that the same as the condenser, or something completely different?

Me Bad. Ive been changing the caps in a tube stereo... Condenser is the right name..

 

ha! I just changed out some caps on my guitar the other day. Hard to get out of that mindset once you start. I'll pick up a new condenser, too.. worth trying.

 

Roger.. I'll test it the right way next time, hopefully I can get to it tomorrow.

 

Good afternoon, everyone.. so I had a couple minutes to go out to the garage to try to get that voltage reading with points closed. I pulled the distributor cap to see if they're closed, and just happened to look at the inside of the cap to spot anything obvious. I found this marring that looks like the rotor was scratching up the inside of the cap. PO said it's a new cap and rotor, maybe cheapo stuff? And could this be the culprit?

 

I tried to get good pictures of the cap, Larry.. it looks fine, I think. I also attached pictures of the points and the inside of the distributor, in general, in case that helps.

 

For the heck of it.. Can you define operating temp.... Reason you've used 10 mins also.

10 mins = cold choke time. motor, coolant,, oil,, is not to OT

OT is longer 20- 30 depending. summer, winter, driveway, city driving highway driving.

 

Ok.. voltage on positive side of coil with ignition on, points closed is 4.98V.

 

Sure thing.. it doesn’t have a gauge on it, just the hot light, but it hasn’t lit up. It starts acting up when the choke pulls off, and it does seem to get worse near the 20-30 minute mark. It never completely dies, but it does get progressively rougher the longer I run it. Could it be overheating, or would that be obvious? It isn’t steaming/smoking at all.

 

OK you fixed the power piston & Im assuming the carb is ok.

So Im back to the coil. have you checked the coil impedance. Hot & cold

good to ok video
.

 

At 1st. look it appears the center of the rotor is NOT making contact of the carbon in the center of the cap. ALSO, the points look like they've been overheated, maybe from over voltage at one time, because they are discolored near the point contact surface.
Just an observation.
MAYBE, just replace the points??? Cheap & easy.

Tom T.

 

I will do this tomorrow when I have more time, for sure. Thanks, Bob!

 

Also Bob, I should’ve mentioned - I did replace the coil. You thinking there’s a chance this one is defective?

Tom, thanks for the input! I’ll give that a shot, too. Like you said, cheap and easy. With the rotor center - probably not advisable to just give it a little touch/slight bend in the right direction, right?

 

new. wow maybe Never Ever Worked.

 

Did you drive this car home? Could the exhaust be plugged?

 

I did not drive it home, but it seems to be flowing just fine. Maybe mouse nest? I did find one up in the front of the hood near the latch.

 

Hey where your exhaust manifold meets the exhaust pipe look for a flapper https://www.summitracing.com/parts/oer-3887023?seid=srese1&cm_mmc=pla-google-_-shopping-_-srese1-_-oer&gclid=Cj0KCQjwjpjkBRDRARIsAKv-0O3Bt9RlYU0DhkgZQe_sFEoXMrG3baxFXxfBH5dppJQUB73OwaYdPS0aAmIbEALw_wcB they seize when not used. with your hand see if you can move it.

if you have one spray it with a penetrating oil. moving or not