Hello, I have a 1967 Chrysler Newport 440 H.O. that runs good when idling and starting out driving. When it hits a higher rpm it starts cutting out until it shifts and allows it to go into lower rpm. I have changed the fuel pump and rod as well as changed out the carborator. I was wondering if anyone else has had this issue before and could direct me where to look next. Thank you
1967 Chrysler Newport 440 cutting out when hitting a certain RPM while driving.
- Thread starter Pat101426
- Start date
- Joined
- Nov 14, 2010
- Messages
- 28,146
- Reaction score
- 27,297
Points or electronic ignition?
Sounds like weak points spring tension.
When I got my '70 Monaco Brougham 383"N", back in 1975, it ran great, never hesitating to advance the speedometer needle to 100mph with just a bit of additional throttle. All was great. But when I started exploring WOT performance, right before it would do its 1-2 WOT upshift, it would start surging before it automatically shifted. This puzzled me as our '66 Newport Town Sedan 383 2bbl never did that, even with its slightly lower WOT shift points. That car would go to 90mph in 2nd gear before the power started to decrease.
I checked the dwell on the points, the AVS float level, base timing, and anything else I could figure out. "Point float" should not be happening at not-quite-5000rpm, as the points were reasonably new and what the Chrysler dealership installed during their check-out activities before I bought the car. I looked at everything I could think of in my large car magazine collection, finding nothing.
Finally, I read something about "spark scatter" in an old Direct Connection Race Manual. Seems that at higher rpms, the oil pump loading variances can twist the distributor shaft enough to momentarily cause the distributor drive shaft to deflect, affecting spark timing several degrees, momentarily, as it does. As they were all directly connected (distributor to oil pump), I pondered that situation.
I had been wanting to change the somewhat unknown brand of oil in the car to Castrol GTX, so I did. Problem vanished with that oil change never to reappear. Perhaps that brand of oil flowed easier through the motor so the oil pump was not experiencing "loading/unloading" quite so much. After that one change, the motor confidently and reliably went to the top of 1st and 2nd with no problems at all, with more Mopower like it was designed to do.
The only other issue that engine had was that if I was "in a hurry" and hit a section of dirt, the on-throttle rpm would flare and the oil light would illuminate. I'd quickly put it in "N", rolling, blip the throttle a few times, oil light goes out, proceed with haste. At that time, the engine had well over 130K miles on it. No main or rod or piston noises, ever. Just something to be aware of.
Prior to this, at about 95K miles, when I took a city street corner too fast, the oil light came on. Nothing worse than a police car might do, but still more than average later g-forces. Put it "N", moving, blipped the throttle a few times, oil back to normal. Made mental note to not do that again. I guess Uncle Tony's comments about Chrysler's unbaffled oil pans are accurate?
I don't remember if I was using 10W-40 or 20W-50? This was back when any Castrol GTX motor oil, especially the 20W-50 viscosity, was considered "motorcycle motor oil", as that was allegedly the main market for it, back then. At least locally.
Just my experiences, your experiences might vary.
CBODY67
I checked the dwell on the points, the AVS float level, base timing, and anything else I could figure out. "Point float" should not be happening at not-quite-5000rpm, as the points were reasonably new and what the Chrysler dealership installed during their check-out activities before I bought the car. I looked at everything I could think of in my large car magazine collection, finding nothing.
Finally, I read something about "spark scatter" in an old Direct Connection Race Manual. Seems that at higher rpms, the oil pump loading variances can twist the distributor shaft enough to momentarily cause the distributor drive shaft to deflect, affecting spark timing several degrees, momentarily, as it does. As they were all directly connected (distributor to oil pump), I pondered that situation.
I had been wanting to change the somewhat unknown brand of oil in the car to Castrol GTX, so I did. Problem vanished with that oil change never to reappear. Perhaps that brand of oil flowed easier through the motor so the oil pump was not experiencing "loading/unloading" quite so much. After that one change, the motor confidently and reliably went to the top of 1st and 2nd with no problems at all, with more Mopower like it was designed to do.
The only other issue that engine had was that if I was "in a hurry" and hit a section of dirt, the on-throttle rpm would flare and the oil light would illuminate. I'd quickly put it in "N", rolling, blip the throttle a few times, oil light goes out, proceed with haste. At that time, the engine had well over 130K miles on it. No main or rod or piston noises, ever. Just something to be aware of.
Prior to this, at about 95K miles, when I took a city street corner too fast, the oil light came on. Nothing worse than a police car might do, but still more than average later g-forces. Put it "N", moving, blipped the throttle a few times, oil back to normal. Made mental note to not do that again. I guess Uncle Tony's comments about Chrysler's unbaffled oil pans are accurate?
I don't remember if I was using 10W-40 or 20W-50? This was back when any Castrol GTX motor oil, especially the 20W-50 viscosity, was considered "motorcycle motor oil", as that was allegedly the main market for it, back then. At least locally.
Just my experiences, your experiences might vary.
CBODY67
Last edited:
cbarge
World Famous Barge in a Budget
Check for loose wires at the coil.........
HI, THE CAR HAS ELECTRONIC IGNITION.
- Joined
- Nov 14, 2010
- Messages
- 28,146
- Reaction score
- 27,297
It’s possible that it got one of those junk China made orange ecu’s when the conversion from points was done. Did you convert it? Is this issue new?
Similar threads
