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Old 06-04-2005, 08:56 PM   #1
JIMs70GMC
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Smile 10 degrees kept the truck from starting!

10 degrees of dwell that is. I just spent the better part of 10 days chasing a problem that ended up being my dwell off by 10 degrees. I rebuilt the carb, replaced ignition wires, replaced the starter, 1 battery cable, fuel filter.
The problem as it manifested it self was similar to flooding, hard to start when cold or after sitting for an hour(hence carb rebuild) I checked for spark and didn't have one so I jumped on the starter/ignition wires. Well this morning I pulled out a dwell meter my dad gave me and after about 10 minutes got it started and checked the dwell and had less than 20 degrees and was running rough, brought it up to 31 degrees and bingo fires all the time, engine sounds better. It seems the dwell was going south over the past several months. I had performed a tune up in april of last year and have only put about 5000 miles on her since then. Plugs looked and so did the cap and rotor. Oh well something else to check.
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1970 K25, 8' stepside bed 350/465/205 44 up front, 60 in the rear 4.10s rolling on 33" Dunlop MTs
1986 K5, 350/465/208 Dana 60/14 bolt from a cucv 36" Super Swampers TSL/SX
1983 K20 w/ CUCV axles, 350/700R4/208 sitting on 37" Goodyears
1986 M1031 6.2 diesel, TH400/NP205 locker in the rear and a LS in the front, all stock for now.....
1986 K30, 350/400/205 dana 60 and 14 bolt. I kept the drivetrain. Body/bad and chassis are gone.
1981 K30, 350/465/205 dana 60 and dually 14 bolt. Has a G80, and a flat bed. Going to replace the flat bed.

1985 K20, 350/400/208 10 bolt and SF 14 bolt. I wonder where I can find some 1 tons. Hmmmmm
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Old 06-04-2005, 09:54 PM   #2
krue
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Just another reason why HEI is for me.
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Old 06-04-2005, 09:56 PM   #3
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good for you! .Those parts you got probably needed replacing anyway and if not you have some spares.
Now do yourself a real favor and swap to an Hei ignition and don't worry about points or dwell again. It' easy to do and it pays big dividends
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Old 06-04-2005, 11:14 PM   #4
kwmech
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Another vote for the HEI. Made that part of my life easier.
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Old 06-05-2005, 12:11 AM   #5
Longhorn Man
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points? What's that?
Had an old mid 70's Chevy dump truck dragged into the shop a couple months ago...since I am the chevy truck guy there, they told me to get it running. hadn't ran in 12 years.
I popped the hood, and shut it 2 seconds later. Told the boss man to give me a $20 and I was goin to the junk yard.
HEI and fresh gas, and I was drivin it.
Stopping it was another story all together...
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Old 06-05-2005, 01:05 AM   #6
stllookn
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Andy...brakes are higly overrated anyway...LOL! Great job on that truck...you ARE the shop go-to guy on old Chevys! Only $20 for a junkyard HEI? That is a great price. I've got to run the points on the Longhorn...it has to remain stock! Not sure how long I will be able to hold out on some of these type of improvements though.
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Old 06-05-2005, 01:27 AM   #7
Longhorn Man
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heck, i only paid 10 bucks for the HEI....and that included the Accel coil, the accel plug wires, and lots of mud on my boots.
I kept the coil and wires for myself.
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Old 06-05-2005, 01:38 AM   #8
Green Machine
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Generally I think as the rubbing block wears down on the points, the gap decreases and dwell increases, eventually the points burn from lack of gap. Did the dwell hold steady or bounce up and down ? You may have bushing and/or shaft wear, that will tend to decrese dwell. Good points and tight bushings should be good for 10,000 miles, if your check dwell ocasionally. Might want to pull your distributor ,take it apart and check it over. The cam can wear out also. A few companies make a conversion to replace the points so it still looks stock, but having said all that , HEI is still better.
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Old 06-05-2005, 07:20 AM   #9
GMC AMI
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Quote:
Originally Posted by JIMs70GMC
10 degrees of dwell that is. I just spent the better part of 10 days chasing a problem that ended up being my dwell off by 10 degrees. I rebuilt the carb, replaced ignition wires, replaced the starter, 1 battery cable, fuel filter.
The problem as it manifested it self was similar to flooding, hard to start when cold or after sitting for an hour(hence carb rebuild) I checked for spark and didn't have one so I jumped on the starter/ignition wires. Well this morning I pulled out a dwell meter my dad gave me and after about 10 minutes got it started and checked the dwell and had less than 20 degrees and was running rough, brought it up to 31 degrees and bingo fires all the time, engine sounds better. It seems the dwell was going south over the past several months. I had performed a tune up in april of last year and have only put about 5000 miles on her since then. Plugs looked and so did the cap and rotor. Oh well something else to check.
Glad to read all is well. I can see where that much dwell out of wack would cause you a problem since the dwell angle controls engine timing. A well set up points dist. purrs like a kitten. HEI is not without it's own set of problem,
left me stranded in Florida, resistor fried. Had that fixed and when I got back to Maine it quit on me again, pick-up coil went. Overall the HEI is a better system, nothing is perfect. Best to own a dwell meter if you run points then adj. is easy to keep her running optimum.
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Old 06-05-2005, 09:11 PM   #10
JIMs70GMC
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Have to get off my lazy ass, and install the HEI distributor that's been in my garage for a year and the internal alt while I'm at it. The dwell was not bouncing around at all when I dialed it in to 31 degrees. I'm dreading the hei because of the firewall clearance on the 4wds.
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1970 K25, 8' stepside bed 350/465/205 44 up front, 60 in the rear 4.10s rolling on 33" Dunlop MTs
1986 K5, 350/465/208 Dana 60/14 bolt from a cucv 36" Super Swampers TSL/SX
1983 K20 w/ CUCV axles, 350/700R4/208 sitting on 37" Goodyears
1986 M1031 6.2 diesel, TH400/NP205 locker in the rear and a LS in the front, all stock for now.....
1986 K30, 350/400/205 dana 60 and 14 bolt. I kept the drivetrain. Body/bad and chassis are gone.
1981 K30, 350/465/205 dana 60 and dually 14 bolt. Has a G80, and a flat bed. Going to replace the flat bed.

1985 K20, 350/400/208 10 bolt and SF 14 bolt. I wonder where I can find some 1 tons. Hmmmmm
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Old 06-06-2005, 06:30 AM   #11
'68OrangeSunshine
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I had a similar gripe on my '68 292 L6. It turned out the condenser had burned out. I had replaced everything else. The condenser was a fancy Mallory unit from the hot rod shop, so naturally it must last longer than the stock ones, since it cost twice as much.(!?) I'll be shifting to Pertronix Ignitor II once I get the new 500 CFM Edelbrock AFB dialed in.
In the old days, you could keep a spare set of points, condenser and rotor in your glovebox, and if you got stranded in the desert, you could still pull a rough tune up enough to get you home. I'll miss that.
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