can not replace spark plug !!

[kuruma]

i finally got around to do a compression test in my 1990 240. I pulled out all of the plugs and set everything up for the test.

There was no problems when I had to pull out the plugs, but I could not get the nozzle of the tester to screw into the first cylinder hole properly. It would go about a 1/4 turn and stop. All the others went in perfectly fine.

After I completed the test except for cylinder 1. I replaced all the other plugs, but the cylindr 1 plug would not screw in at all. After a few trys I noticed metal flakes around the threaded part pf the plug. I kept trying for a while, but could not get it in at all. It didnt thread at all.

I dont really know what to do now. So I came here to ask for suggestions on my next step.

BTW, the tests for all the other cylinders came out perfect (179 across the board) , so once/if I get this worked out its gonna get turboed with stock internals.

[180fan]

might wanna pray it's not cross threaded but if it is, might wanna get a coil kit for that busted plug hole.

[DAEDALUS]

Use a spark plug thread chaser first. It's basically a tap to clean up the threads. You can get it at any auto store. It does sound like the plug was cross-threaded when it was installed. Hopefully the chaser will leave enough bite for the plug, but if not, you will need to install a helicoil. After using the chaser rig a vacuum to a small hose and suck out the shavings that will fall into the combustion chamber.

[kuruma]

Thanks alot guys. I will go pick up a re-threader... and see how it goes. If i have to then coil kit it is. Hopefully the AAP around here will have everything i need.

I am in the market for a new high toque battery powered drill. Do any of you have suggestions. I am looking for something that is powerfull enough to drill through tough materials, such as busted screws, and the spark plug hole.. etc.

thanks again

[DAEDALUS]

I love my DeWalt XRP 18V drill/driver. Kind of pricey, but it rocks. The torque part is why it costs a lot, but just for drilling, you don't need very much torque, just high speed.

[kuruma]

thanks.. I will look into it.