TheAMCForum.com Homepage
Forum Home Forum Home > The Garage > AMC 6 Cylinder Engine Repair and Modifications
  New Posts New Posts RSS Feed - Spark Plug Read, please....
  FAQ FAQ  Forum Search   Events   Register Register  Login Login

Click for TheAMCForum Rules / Click for PDF version of Forum Rules
Your donations help keep this valuable resource free and growing. Thank you.

Spark Plug Read, please....

 Post Reply Post Reply
Author
Message
sed0007 View Drop Down
AMC Apprentice
AMC Apprentice


Joined: May/14/2013
Location: Cleveland Ohio
Status: Offline
Points: 122
Post Options Post Options   Thanks (0) Thanks(0)   Quote sed0007 Quote  Post ReplyReply Direct Link To This Post Topic: Spark Plug Read, please....
    Posted: Jun/08/2023 at 2:01pm
Have had this 69 Rambler for three years, now.  Bought it w/ 26,000 miles, now have , 33,000 miles.   Other than a water pump, I've done nothing to this car but change the oil once.   It always starts, and while my daily driver was down for a few weeks waiting for brake parts with the dealer, I drove the Rambler to work every day for two weeks, round trip 32 miles, half highway and half surface streets.  Always gets 22 mpg.   It's the 199 straight six with 3 on the tree.

Previous owner has an old Cherry Bomb muffler, an the car is starting to backfire when off throttle.  My daily driver is back, so I decided to pull the plugs.   I don't think they look too bad, and are all gapped at  .033.


Tell me what you think.   Next step is to check timing and play with the carburetor.  one of the pics is a 2nd image of the 2nd or 3rd plug, as it was a lot different on each side.  
















Edited by sed0007 - Jun/08/2023 at 2:18pm
'64 550;'63 660;'62 Classic Custom; '69 Rambler 440


http://walkingwithstefan.wordpress.com/
Back to Top
Heavy 488 View Drop Down
AMC Addicted
AMC Addicted


Joined: Apr/27/2019
Location: In the
Status: Offline
Points: 3529
Post Options Post Options   Thanks (1) Thanks(1)   Quote Heavy 488 Quote  Post ReplyReply Direct Link To This Post Posted: Jun/08/2023 at 4:18pm
Backfiring when letting off the throttle is more likely a leak somewhere in the pipe. It'll draw in air and light off the richer mix from deceleration .
Plugs look fine
Back to Top
purple72Gremlin View Drop Down
AMC Addicted
AMC Addicted
Avatar
Charter Member

Joined: Jul/01/2007
Location: Illinois
Status: Offline
Points: 16591
Post Options Post Options   Thanks (1) Thanks(1)   Quote purple72Gremlin Quote  Post ReplyReply Direct Link To This Post Posted: Jun/08/2023 at 6:16pm
What 488 said.   Maybe exhaust donut on manifold is starting to leak? 
Back to Top
sed0007 View Drop Down
AMC Apprentice
AMC Apprentice


Joined: May/14/2013
Location: Cleveland Ohio
Status: Offline
Points: 122
Post Options Post Options   Thanks (0) Thanks(0)   Quote sed0007 Quote  Post ReplyReply Direct Link To This Post Posted: Jun/08/2023 at 9:05pm
Thanks!! I'll get under it and see.  I was worried about being too lean.
'64 550;'63 660;'62 Classic Custom; '69 Rambler 440


http://walkingwithstefan.wordpress.com/
Back to Top
FSJunkie View Drop Down
AMC Addicted
AMC Addicted
Avatar

Joined: Jan/09/2011
Location: Flagstaff, AZ
Status: Offline
Points: 4741
Post Options Post Options   Thanks (0) Thanks(0)   Quote FSJunkie Quote  Post ReplyReply Direct Link To This Post Posted: Jun/12/2023 at 12:49am
If it has good power and doesn't bog or hesitate at light to mid throttle when the engine is halfway warmed-up, then it is perfect. 

They are always darker on one side.

Very good oil control. 


1955 Packard
1966 Marlin
1972 Wagoneer
1973 Ambassador
1977 Hornet
1982 Concord D/L
1984 Eagle Limited
Back to Top
sed0007 View Drop Down
AMC Apprentice
AMC Apprentice


Joined: May/14/2013
Location: Cleveland Ohio
Status: Offline
Points: 122
Post Options Post Options   Thanks (0) Thanks(0)   Quote sed0007 Quote  Post ReplyReply Direct Link To This Post Posted: Jun/12/2023 at 5:18pm
Thanks!!  It bogs sometimes, that's why my nest step is to look at the points and then adjust the carb.   I have a big vacuum gauge, just wondering where to access the vacuum so I can look at timing and idle/mixture.
'64 550;'63 660;'62 Classic Custom; '69 Rambler 440


http://walkingwithstefan.wordpress.com/
Back to Top
Heavy 488 View Drop Down
AMC Addicted
AMC Addicted


Joined: Apr/27/2019
Location: In the
Status: Offline
Points: 3529
Post Options Post Options   Thanks (0) Thanks(0)   Quote Heavy 488 Quote  Post ReplyReply Direct Link To This Post Posted: Jun/12/2023 at 6:54pm
Can't speak for all systems, but several OE injection systems cut fuel completely on hard deceleration until a set rpm ( in the neighbood of 1,500; rpm )Good factory manuals state this and I've watched it on my widebands.
Back to Top
 Post Reply Post Reply
  Share Topic   

Forum Jump Forum Permissions View Drop Down

Forum Software by Web Wiz Forums® version 12.03
Copyright ©2001-2019 Web Wiz Ltd.

This page was generated in 0.125 seconds.
All content of this site Copyright © 2018 TheAMCForum unless otherwise noted, all rights reserved.
PROBLEMS LOGGING IN or REGISTERING:
If you have problems logging in or registering, then please contact a Moderator or