View Full Version : '78 2F - crusty plugs

08-09-2007, 09:30 AM
I pulled the plugs from my '78 2F engine last night to do a compression test, and they were quite crusty. Refer to pix 1 and 2. They are not oily, and the black crustys flaked off reasonably easily - they weren't baked on too hard.

I suspect the valve stem seals are a bit weak (they're 14 years old - FelPro, not Toyota) and I think this is just ash from the oil leaking down. I se blue puffs on shifts when cold, but huge ones. Compression is fine - 100-108, at 7000' elevation, so 121-130 at sea level. Oil in the cylinders raised each one 4 PSI, so rings are ok. I have not driven it it hard on the highway for quite some time, so this may be 'city buildup'.

The final shot shows the plugs after I used Jeff Zepp's Chinese-made spark plug cleaner/sandblaster. I drove the FJ today and it runs much better. Note these are Denso OEM heat range plugs. The engine has less than 100K miles and I run 10w-40 conventional oil.

Beyond either replacing the valve stem seals, or doing a valve job and milling the head for higher compression ;-), any suggestions? A long highway drive with Rising Sun on a 4WD trip?

Thanks - Steve