ragtopfury
Well-Known Member
First a short background on the leading up to the issue at hand...... So Jake picked up and dragged home a 96 Ram 1500 extended cab 4x4 for next to nothing because the previous owner has been messing with a no-start issue for almost a year and is mad at it. The truck has 153k miles on its 360, only 2 rust spots the size of a 1/2 dollar, the trans was rebuilt 3 years ago and the interior is dang near perfect. He was going to just part it out, but we couldn't stand not knowing why it wont start.
Doing a visual under the hood, we see that the coil's case is split open on the top and down the back side. The coil hangs off a bracket on the front of the right head. I just happen to have a spare for the Durango, so we try it- Different plug..... Booger-rig a couple of connectors just to test it out and SHAZZAM - The truck starts right up and has great oil pressure, no engine noise and goes in and out of gear.. $34 later for a new coil and he's in business... ...
However, there is an annoying "spark jumping to something on the left side of the engine" sound, and a miss..... The PO had put plugs/wires/cap/rotor on it, among a few other odds and ends, so I'm thinking cheap plug wires.... By now it is dark out, so I have him start it back up so we can look for the source of arcing. I figured it'd be a lot easier to see in the dark, as opposed to feeling around or swapping out plug wires before we tested them.
Well, it was easy enough to see - #3 plug, where it goes into the head looks like Ft McHenry on the 4th of July. No problem - gotta be a loose or cracked porcelain part of the plug....NOT! The PO has cross-threaded the plug. It wont go any farther. It seems to only come about half way back out. Score one for Murphy and his dang law!
Never dealing with a cross-threaded plug before, how screwed are we likely to be? What are the chances the plug comes out with messed up threads and the threads in the head will be fine???? What's the chances the PO cracked the plug at the top of it's threads, and when it binds up at about the half way out point, will it break off leaving the cross-threaded base in the head? Is the head going to have to come off?
Doing a visual under the hood, we see that the coil's case is split open on the top and down the back side. The coil hangs off a bracket on the front of the right head. I just happen to have a spare for the Durango, so we try it- Different plug..... Booger-rig a couple of connectors just to test it out and SHAZZAM - The truck starts right up and has great oil pressure, no engine noise and goes in and out of gear.. $34 later for a new coil and he's in business... ...
However, there is an annoying "spark jumping to something on the left side of the engine" sound, and a miss..... The PO had put plugs/wires/cap/rotor on it, among a few other odds and ends, so I'm thinking cheap plug wires.... By now it is dark out, so I have him start it back up so we can look for the source of arcing. I figured it'd be a lot easier to see in the dark, as opposed to feeling around or swapping out plug wires before we tested them.
Well, it was easy enough to see - #3 plug, where it goes into the head looks like Ft McHenry on the 4th of July. No problem - gotta be a loose or cracked porcelain part of the plug....NOT! The PO has cross-threaded the plug. It wont go any farther. It seems to only come about half way back out. Score one for Murphy and his dang law!
Never dealing with a cross-threaded plug before, how screwed are we likely to be? What are the chances the plug comes out with messed up threads and the threads in the head will be fine???? What's the chances the PO cracked the plug at the top of it's threads, and when it binds up at about the half way out point, will it break off leaving the cross-threaded base in the head? Is the head going to have to come off?
