Spark plug torque (from the Bosch site)

[K-Jetronic]

Don't know if you already know (I didn't):

from the official Bosch site

Quote:

3/ Screw in the new spark plug finger tight. Plugs with sealing ring (flat seat) must be turned through a 90".

4/ Plugs without sealing ring (conical seat) must be turned through 15".

regards,

Gerko
1978sc

[chuckw951]

Just bought a set of bosch spark plugs. The box indicates torquing the plugs to 25Nm (19ft lbs.) Not sure what the porsche books say.

[K-Jetronic]

Hi chuck,

I did know about the torque, but found it kind of difficult to set with the toolkit sparkplug tool. Always had to do it by sense. Now it's easy, just turn it hand tight and then a quarter of a turn (90") with the tool and your set (according to Bosch of course). Gives me more peace of mind this way.

Regards,

Gerko
1978sc

[89911]

25lbs is too high for some. I've been using the feel of the washer being crushed with the Porsche tool. I torqued them to 25lbs previously and my mechanic said they felt way too tight.

[kqw]

89911,

I believe he says 25nm (nanometers)or 19ft/lbs

[Randy Webb]

the inches above must mean degrees

the nanometers.... you mean N-m (Newton - meters) the SI unit of torque -- a nm is a very teeny length measurement -- virus level or element spacing in semi-con chips

[Superman]

When the crush washer starts to crush, you're just about at 19 lb/ft. When you feel the crush washer finish crushing, you're there.

[89911]

Originally posted by kqw
89911,

I believe he says 25nm (nanometers)or 19ft/lbs

Sorry, meant nanometers. The point is that I think you have better feel with experience and a well known tool then using an innaccurate torque wrench, especially at the odd angles under the hood.

[kqw]

Randy, you are correct...Newton Meters vs. Nano...

Too many hours in the lab......I'm going home