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Old 09-06-2004, 06:22 PM   #1
bean
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need help

I have a 69 with a strt 6. Problem is when it warms up it seems to run rough. If I get it on the highway and drive about 20 minutes it will die when I pull off to exit. Otherwise the truck runs great. The engine was rebuilt about a year and half ago. What's up?
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Old 09-06-2004, 06:36 PM   #2
Sweet72
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Next time it does it see if you're getting ignition, if not your coil is probaby the culprit. If spark is ok, maybe it's vapor-locking.
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Old 09-06-2004, 06:41 PM   #3
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Thumbs up maybe....

remove air cleaner.....be careful....while running place hand over the top of carb....to limit the air intake....not covering completly....
if it idle's up...you got a vacuum leak.......

could be that while cold choke is on.....running richer....after warm...no more choke....thus leaner mixture.....engine no likey....


just a thought.....
your pal....mark
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Old 09-06-2004, 06:42 PM   #4
bean
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If its vapor locking what would I do. The coil is a petronix and isn't all that old but I'll keep that in mind. Anything else you can think of?
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Old 09-06-2004, 06:45 PM   #5
bean
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This truck still has the original manual choke.
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Old 09-06-2004, 06:52 PM   #6
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Thumbs up

may still have a vacuum leak....

try the hand...over the carb....trick...can also spray carb. cleaner around the lower carb. base and manifold while running to check throttle plate rod seals
and base gasket..and intake to head gasket....
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Old 09-06-2004, 09:47 PM   #7
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My vote, the coil is the culprit. In my experience when they are about to give up the ghost they tend to malfunction when they warm up.
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Old 09-07-2004, 06:58 AM   #8
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I've had that happen too, they get "funny" when they get warm. Mine used to be hard starting when hot, acted like it was flooded but it wasn't. Turned out to be either the coil or the module going bad. (not sure which it was since I replaced both at that same time)
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Last edited by bobs409; 09-07-2004 at 07:01 AM.
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