been slowly going thru the car, pulled one of the autolite 26's and it crumbled and fell apart, autozone gave me autolite 85's. i read that with a HEI you can gap them at .045, i did that and it ran horrible, i could barely get it above 30 mph. i regapped at .034 and now i cant even get it to start. any ideas???
327 spark plug issues
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What year is your 327? There is a big difference in the Autolite 26 & Autolite 85's. The 26's are a tapered plug, 5/8" hex and the 85's are a gasketed plug with a 13/16" hex. The two also have a different reach. Did the motor run with the 26's?
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Check the strength of the spark with a spark tester. If the spark is blue it's strong, if it's yellow it's weak and something in the ignition system is on it's way out. By the way it sounds it's either losing or lost spark or it's lost fuel.
Gaps have very little effect on how it will run. You also have to keep in mind, the larger the gap, the harder the ignition has to work to arc the gap of the plug. Electricity is just like water, it's smart, but lazy. It will always take the path of least resistance so if there is a place it can arc to that's less resistance than the spark plug it will by all means do so.
If you've recently converted it over to a HEI check the voltage going to the distributor. A HEI MUST get a solid 12 volts to run properly. However, it can run on as low as 8 volts, but it'll run awful as a result.
Gaps have very little effect on how it will run. You also have to keep in mind, the larger the gap, the harder the ignition has to work to arc the gap of the plug. Electricity is just like water, it's smart, but lazy. It will always take the path of least resistance so if there is a place it can arc to that's less resistance than the spark plug it will by all means do so.
If you've recently converted it over to a HEI check the voltage going to the distributor. A HEI MUST get a solid 12 volts to run properly. However, it can run on as low as 8 volts, but it'll run awful as a result.
yeah it did run and i noticed the difference in the plugs as well, ive been chasing a misfire, when i was going thru the plugs i found a completely melted down plug wire head hiding out of view behind the headers so im sure that was it. i have no idea what year it is, is there any way to tell?
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Is this a stock 327? With HEI AC R44T Autolite 145,683,85. Gap 35-40 no more! Have the module and pickup coil tested.
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Even so one plug is a 13/16 and the other is a 5/8 you can still use the 5/8 plug in the older heads without issues. When we got tired of fooling with the larger size of the plug we went down to the 5/8 plug and ran them for years without issue. Keep in mind also, since your using the larger plugs when it first starts to feel snug you have about another 3/4 turn to go before it's tight, many stop when it first feels snug and why is because the metal gasket around the plug hasn't contoured to the shape of the plug opening. When it's just snugged and the gasket hasn't contoured once the plugs have a hot to cold cycle they'll be so loose you'll be able to remove them by hand so make sure you go past the initial snug point otherwise half the compression will go past the spark plug on the power stroke.
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Do not try the 85 Autolite it is a non resistor Marine plug. The AC R44 and Autolite 145,683 all cross-reference. If you go to a auto parts store their computer shows R43,R44,R45 (which are different heat range) and the Autolite 145.
i went back to the 62's, i figured its been running fine on them for the 2 months ive had, its wanting to start but still not running, i checked the gap their at .035, double checked the wires. when i pulled them to check they almost all had gas on them, it ran fine before i pulled them so i know it to be something small im overlooking.
no luck still, gapped right, firing order right, but it wont start. which is crazy because it ran "good" before pulling the plugs. ive been driving daily. i even pulled them all and let them air out for a couple hours since they were wet with gas, i wonder if their gonna to sit longer?
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What are 62's, you lost me here! When resistor plugs get flooded out I throw them away and buy new ones. I went to a Vette forum to check the spark plugs their 327's use. I read that 327's use a R44 AC plug before 1971, in 1971 GM went to the tapered seat so R44T. R43 plugs are cold plugs used for high performance engines with 11:1 compression. R44 was for street driving. R45 was a hotter plug used when having problems with fouled plugs. BTW it was said that the R44 is no longer made. What the letters mean: R= Resistor, 4= 14mm, 4= heat range, T= tapered seat, S= extended tip, x= wide gap. See this website for a cross reference to other brands of spark plugs. Alternative spark plugs for AC DELCO R44. Have you taken #1 spark plug wire and grounded to metal to see if firing?
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If it won't start and the plugs are wet, it means you have a voltage or spark problem. Pull all the plugs, hook a plug up to a spark plug wire and ground the plug base by laying it against the exhaust or somewhere similar. Have someone crank the engine over with the key and watch the color of the spark at the plug. If it's anything but blue, you have a different problem. It sounds like you're not getting much voltage to the plugs from the HEI. Check and make sure you are getting a solid 12v to the HEI and check all the grounds.
auto lite 62's, its a 5/8's plug, thats what was in it when i bought it, since its been driving previously on them i went to them. just changed out the plug wires as well no luck, ill have someone crank it for me and take a look.
thanks!
thanks!
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Trobleshooting a GM HEI
Here is an article on troubleshooting your GM hei. There is alot of information. Technical Reference #5
Here is an article on troubleshooting your GM hei. There is alot of information. Technical Reference #5
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Identifying a GM Block
your engine. You can identify any part you have as long as you have the casting number. If you have any problems let me know if I can help. http://www.nastyz28.com/sbchevy/sblock.php
Go to this site for identifying
your engine. You can identify any part you have as long as you have the casting number. If you have any problems let me know if I can help. http://www.nastyz28.com/sbchevy/sblock.php
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