Crush washer

[v65]

AS to prior notes that the 32 ft-lbs is probably a "dry thread" spec. THat sure would be stupid since we are talking about a service manual (not an assembly manual) and an oil drain plug that will never have dry threads for the rest of its life.

The other side of that argument is that if 31ft-lbs is a wet spec, then the dry spec is near 62. As you said, I don't think so.

 

[Fred W]

AS to prior notes that the 32 ft-lbs is probably a "dry thread" spec. THat sure would be stupid since we are talking about a service manual (not an assembly manual) and an oil drain plug that will never have dry threads for the rest of its life.

The other side of that argument is that if 31ft-lbs is a wet spec, then the dry spec is near 62. As you said, I don't think so.

Yeah, it's just a wrong spec.

 

[charismaticmegafauna]

31 lbs/ft of torque on a 14mm fastener is about 1/2 the generally recommended (proper) torque value for that size fastener installed in a non-ferrous medium.

You can't be serious.

I am serious.

You're saying that because it's a 14mm plug you think the "generally recommended" torque value for it in an aluminum drainpan should be 62 ft-lbs?

It's written in 'tech' manuals, everywhere. 31~32 is only half of what's written.

The torque spec is not solely derived from the diameter of the threads. It also matters how many threads are engaged and the thickness and composition of the threaded material. I can see if we were talking about a solid aluminum block of some kind and a 14mm bolt that had an inch and a half of threaded engagement, but I guaran-damn-tee you'll be stripping those threads in our wimpy drain pan LONG before 62 ft-lbs. *Guys are stripping them at 32 ft-lbs now.*

Maximum thread 'purchase' is reached at a length equal to the thread diameter -- no more length is necessary.

*Guys* do some dumb 's#*t' -- they've been stipping threads since the first wrench was made....

 

[v65]

Anybody happen to have a spare pan lying around? I'd like to see that bolt get torqued to 62 ft-lbs dry without stripping.

For you engineering types, let's just say you have a bolt that require a torque of 62 ft-lbs. Then what strength bolt/nut combination would be spec'd so that you could be assured it wouldn't strip?

 

[mike25]

"Maximum thread 'purchase' is reached at a length equal to the thread diameter -- no more length is necessary."

I believe that to be true, as long as you are threading a steel bolt into a steel nut (pan). Aluminum requires more,

I believe it to be 1 1/2 to 2 diameters. And, I hardly ever change crush washers.