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Do the spark plug crush washers on a 61 /6 225 belong on the inside or outside of the spark plug cup?

From what I read on the slantsix.org site, sounds like you leave the washer on the plug and install it into the tube. I have a 68 slant, and my year the washer is removed.

Drool tube heads need the washers removed and use this plug NGK ZFR5N.

Okay, I'm really confused now. Borrowed this from another forum:
If you look in the pre 63 heads the spark plug threaded hole has NO machined bevel on the opening, just a drilled and tapped hole. 63-74 have a machined bevel at the mouth of the hole, perfect for the taper of the tube and the washerless plug. If you look at the drool tube small end, you'll probably notice the 45 taper the end was formed with on a 63-74 while the pre 63 head that takes a crush washer will be flat.

Ok I see your point about the 61-62 engines. Here is the TSB if ya ant to read it yourself. http://www.hamtramck-historical.com/ima ... /63-10.jpg I honestly never read about this before. If it makes since to you to use the washers then do it. I don't on my 64 or 73 /6s. I would use the extended nose plugs and it seems my engines idle and run better. I found the discussion on /6 board and Dan seems to know hat he is talking about. I've chatted with him before and taken his advise. http://www.slantsix.org/forum/viewtopic ... 19&t=14125

61stepside wrote:Do the spark plug crush washers on a 61 /6 225 belong on the inside or outside of the spark plug cup?

And btw either leave the washers on or off the plugs but, DO NOT try to put the washers between the drool tube and the block.