moosestang

Anyone have problems with a plug not sealing? I thought I might have been down on power when I went to the track a few weeks ago, so decided to pull the plugs. #8 coil boot had that rust colored powder all over it. The plug felt tight when removing it, but it was clear that I was loosing compression past the plug.



I stuck my camera down the hole to get a better look.


I just replaced these plugs less than 8 months ago. I took one of my old plugs and tightened/loosened it a couple of times and then gave it a few foot lbs more torque. Not sure how to clean the seat.

moosestang

I can't even find a chaser to fit this stupid thing! I was hoping there was a thread chaser that would also clean up the seat.

Simon1

Only reason that would happen is if water got to the threads from above or below.

How about a wire brush that size? Put some type of penetrating oil with the plug mostly in and let it seep. Brush a little bit and then call it good.

I would concerned with debris getting into the cylinder, but, I guess the worse piece that could get in there would be pieces of the metal brush. Maybe use plastic instead.

Try putting some anti sieze on it?

moosestang

I thought about the anti seize. it should act as a mild abrasive.

Goldenpony

I think I'd try a bit of Scotch Brite on the end of a dowl of some kind. I'd also keep looking for some kind of tap or thread chaser to run down the threads. Ford recommends NOT using antisieze on plug threads. Good luck Buddy.

tw1234

http://www.homehardware.ca/en/rec/in...mdf/R-I6424997

When I did the plugs in my F150 I used a BBQ venture brush to clean the threads of the head.

I just sprayed some carb cleaner on the bristles and spun it into the threads until they were clean. A slight rinse with CRC QD into each hole and installed new plugs, no anti-seize and torqued to spec. I didn't worry about a little dusty dirt falling in the cylinder as I had used compressed air to clean the plug wells just before removing the plugs on their last thread turn out.

For safety: Test the brush before using it for sturdiness and possible bristle break down due to the chemical your using before inserting into the cylinder threads. You don't want to loose part of it into the cylinder.

Goldenpony

Another thing that might work is a brass bristle gun brush. Look at different caliber brushes and use one that seems about right.

moosestang

That looks interesting. I might have to stop by lowes. I think a piece of sand or carbon off the previous plugs got jambed between the plug and seat causing it to sit a little cockeyed. No matter how much i blow out the holes, some **** always stays in there. I even turn the plugs out a few turns and blow the holes again. Living on a dirt road, there was always sand in my spark plug wells.


As soon as the motor cools off, i'm going to pull the cop and see if that blown-rust colored dust is all over the place again.

moosestang

plug boot looked good today, must have been a fluke. I'm assuming it's been leaking compression since the last plug change.

Chromeshadow

An old trick to chase threads is to cut a vertical line in a bolt with a hacksaw in a couple of places. Not sure if you can do something similar with a spark plug itself.