Spark Plug installation, Used a thread chaser. Options

[malcolm2]

Blast away if you wish. Here is the deal.

I have a CHT on 3 so i installed it 1st. Removed the washer and started screwing in by hand. Did not get far. So i got my thread chaser and slowly moved it in and out.

Pulled some metal out each time. Added some anti seize to the threads and the plug threaded in mostly by hand. #4 struggled much less. fewer metal bits. #1 went in by hand all the way and #2 was a bitch with some bits. But after the chasing it went in nicely.

So what is the verdict on lite metal shavings and bits?

I don't think i really had a choice. Without chasing the threads the spark plugs could have done some real damage.

picture is from the 3 cylinders that required the ratchet on the chaser.

[emerygt350]

Bad cross thread? Are you familiar with the heads or could a previous owner been up to something?

[Ishley]

At the very least I would rig up a small hose to fish around and vacuum it out the best I could.

[DC_neun_vierzehn]

Did you put grease on the thread chaser so that the shavings would stick to the chaser? If you did that and then wipe the chaser clean and re-apply fresh, clean grease every half turn, most shavings can be captured before falling into the cylinder. It’s very time consuming to do but I found it to be very effective in keeping the shavings out.

[malcolm2]

Did you put grease on the thread chaser so that the shavings would stick to the chaser? If you did that and then wipe the chaser clean and re-apply fresh, clean grease every half turn, most shavings can be captured before falling into the cylinder. It’s very time consuming to do but I found it to be very effective in keeping the shavings out.

i used anti-sieze. that is the gray-ish black color smudge on the paper towel. it picked up the bits. then i cleaned it and wiped it on the paper towel in the picture.

Putting it at the midway point of the chaser, i could tell if the chaser went the full depth, cause the anti-sieze smeared on the tool's threads as far as it went in.

[malcolm2]

Bad cross thread? Are you familiar with the heads or could a previous owner been up to something?

I was one of the last REBUILD customers for Len Hoffman. So he worked on these way back. maybe 13 or even 15 years ago??? And they were original to this car. one of the POs had a valve seat break up and ruined one cylinder. But he fixed it right up.

I remember having some struggles during some of my plug testing. So anything screwed up was by me, but nothing stripped. Had to chase the plug holes once before IIRC.

Clark