seriously stumped
Thread Starter
Racer
Joined: Jan 2013
Posts: 300
Likes: 10
seriously stumped
Cylinders# 8,6,4 are ice cold while 2,1,3,5,7, are firing . I have good fire from the wires, thought maybe wires out of order since I had them off but according to the manual they are in the right order. Engine starts right up, no backfires just rough rough. I did install a low profile vacuum fitting but pulled the carb and looked in the runners. No issues. Pulled valve covers, all are working. Any ideas at all???
Pro
Joined: Oct 2011
Posts: 743
Likes: 71
From: Jarrettsville Maryland
Cylinders# 8,6,4 are ice cold while 2,1,3,5,7, are firing . I have good fire from the wires, thought maybe wires out of order since I had them off but according to the manual they are in the right order. Engine starts right up, no backfires just rough rough. I did install a low profile vacuum fitting but pulled the carb and looked in the runners. No issues. Pulled valve covers, all are working. Any ideas at all???
Le Mans Master
Joined: Dec 2006
Posts: 8,837
Likes: 1,028
Cylinders# 8,6,4 are ice cold while 2,1,3,5,7, are firing . I have good fire from the wires, thought maybe wires out of order since I had them off but according to the manual they are in the right order. Engine starts right up, no backfires just rough rough. I did install a low profile vacuum fitting but pulled the carb and looked in the runners. No issues. Pulled valve covers, all are working. Any ideas at all???
Burning Brakes
Joined: Sep 2009
Posts: 1,124
Likes: 140
From: Western New York
If you had your wires off, I'd check and make sure that 4,6,and 8 are pushed all the way down into the distributor cap. Also check the inside of the cap and make sure there are no problems there, like broken contacts @ 4,6,8. When you say they are ice cold, are you referring to temperature with a thermal gun at the exhaust manifold, or meaning there is no spark at those plugs? If you have spark but the cylinders are cold, then I'd replace those 3 plugs first. If no spark at the wires, go back to the distributor and check that and then put in a new wire on one cylinder and see if you get spark. Let us know what you find.
Duane
I reread your original post and saw that you had good spark at all the wires. I'd start by replacing the plugs in 4,6,8, and see what happens. Sounds like the problem would start there.
Duane
I reread your original post and saw that you had good spark at all the wires. I'd start by replacing the plugs in 4,6,8, and see what happens. Sounds like the problem would start there.
Last edited by Duane4238; Feb 11, 2018 at 09:24 PM. Reason: addition
Team Owner
Joined: Jan 2006
Posts: 37,637
Likes: 3,118
From: Crossville TN
Any possibility that The contacts in the distributor cap were mismachined...so that there is too much air gap between those contacts and the rotor contact when it comes around to 8, 4, 3, 6 positions?
I know that I have seen a "Zone" dizzy cap with just that problem. Change the cap to an old one and see if the problem goes away.
I know that I have seen a "Zone" dizzy cap with just that problem. Change the cap to an old one and see if the problem goes away.
Last edited by 7T1vette; Feb 11, 2018 at 10:53 PM.
Le Mans Master
Joined: Apr 2011
Posts: 6,284
Likes: 1,171
From: Hermosa
Are those cylinders getting fuel? Pull the plugs, they should be all wet with fuel if they are.
If fuel then check ignition,
If ignition and fuel then check compression.
Should be a pretty strong fuel odor out the exhaust too if you got three cylinders with fuel but not firing.
If fuel then check ignition,
If ignition and fuel then check compression.
Should be a pretty strong fuel odor out the exhaust too if you got three cylinders with fuel but not firing.
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Burning Brakes
Joined: Sep 2009
Posts: 1,124
Likes: 140
From: Western New York
So, 8 members have given their suggestions, all of which should have given you an answer had you used them.
You've never replied. Have you found the problem? Did any of the suggestions help? What have you done? It's quite aggravating when someone posts a question and then disappears. How about letting everyone know?
Duane
You've never replied. Have you found the problem? Did any of the suggestions help? What have you done? It's quite aggravating when someone posts a question and then disappears. How about letting everyone know?
Duane
Le Mans Master
Joined: Aug 2017
Posts: 8,336
Likes: 2,810
From: Cool Northern Michigan
So, 8 members have given their suggestions, all of which should have given you an answer had you used them.
You've never replied. Have you found the problem? Did any of the suggestions help? What have you done? It's quite aggravating when someone posts a question and then disappears. How about letting everyone know?
Duane
You've never replied. Have you found the problem? Did any of the suggestions help? What have you done? It's quite aggravating when someone posts a question and then disappears. How about letting everyone know?
Duane