Frank Acampora
Supreme Mariner
Thread starter- Joined
- Jan 19, 2007
- Messages
- 12,004
This post is actually for you fellows who have in the past questioned the use of bent electrode plugs to replace surface gap plugs.
I recently bought a '79 Chrysler 140. Didn't have much time when I got it home so I just did a basic compression test--thumb over the plug hole. First, I noticed that it had L82C plugs instead of L20 or UL18. I thought, "Not Good!" Then I found no compression on #3 cylinder and #3 plug gap was filled with aluminum throw-off.
Well, today it is raining so instead of taking out one of my boats I decided to remove the 140 head. Guess what? Just as I suspected, #3 piston had a beautiful 1/4 inch hole in the crown right at the plug location. #2 and #4 had less damage to the baffle, but enough that I would replace them also.
Note that this engine has never been dis-assembled. The cross hatch marks from factory honing are still visible in all the liners and there (luckily) is no scoring of cylinder walls. This is strictly a problem caused by use of incorrect spark plugs.
So: There you have it! Proof! Bent electrode plugs are hotter than surface gap plugs and WILL harm Chrysler and Force engines.
I recently bought a '79 Chrysler 140. Didn't have much time when I got it home so I just did a basic compression test--thumb over the plug hole. First, I noticed that it had L82C plugs instead of L20 or UL18. I thought, "Not Good!" Then I found no compression on #3 cylinder and #3 plug gap was filled with aluminum throw-off.
Well, today it is raining so instead of taking out one of my boats I decided to remove the 140 head. Guess what? Just as I suspected, #3 piston had a beautiful 1/4 inch hole in the crown right at the plug location. #2 and #4 had less damage to the baffle, but enough that I would replace them also.
Note that this engine has never been dis-assembled. The cross hatch marks from factory honing are still visible in all the liners and there (luckily) is no scoring of cylinder walls. This is strictly a problem caused by use of incorrect spark plugs.
So: There you have it! Proof! Bent electrode plugs are hotter than surface gap plugs and WILL harm Chrysler and Force engines.