mj1pate

What is the torque spec for the oil bypass bolt, #35 in the diagram ? I didn't see a torque spec identified for the bolt, as named. Thanks...

Bill Ball

Yes, the naming of this part in the WSM is confusing. The assembly is referred to as the "bypass valve", distinguished from the smaller "pressure relief valve" assembly in front of it, deduced by reading the part descriptions on the WSM in volume 1, pages 17-2 to 17-4. The plug, or "screw" as the PET calls it, for the bypass valve is an M24 thread, deduced from the dimensions of the sealing ring used under it. So, if you go to the engine bolt torque page, volume 1, page 10-8, you see the "pressure release valve plug" and then a more cryptic "short-circuit valve screw-in flange" that is M24. That's it. It would have been nice if they had called it the bypass valve plug.

Mrmerlin

Nice job on the research Bill

Bill Ball

I went through this recently trying to find the torque for the oil cooler hose flange on the block, which is also cryptically described.

Rob Edwards

This is a very timely subject for me. It may have been covered here before, but I'd like to know how one properly torques the fittings for oil cooler hoses. If one has a bigass crowfoot wrench, and you can actually get your torque wrench in place on the fitting, what's the math that converts the angle at which you're turning to a proper torque value?

Or is "F'n tight" good enough for oil cooler lines that you don't want coming loose?

Sorry for the stupid non-math-having/biologist question

blown 87

Rob, go over to Snap-Ons web site, they have all the formulas there, it has just been a while since I needed them or I would give you a link.

Bill Ball

Measure the distance from the drive head of the wrench to the point of the grip where you place your hand. Then measure distance again with the crowfoot on, from the center of the foot. Torque is directly related to that distance, the length of the lever arm. So, if this distance is increased 10%, you would need to reduce the torque setting by 10%.

mj1pate

Thanks for researching this, Bill. That 50 ft-lbs of torque for the bypass plug into the aluminum block is a chunk of torque. That's the spec; but torquing that plug into aluminum will be a nail biter, in fear of that dreaded, sudden "give" while tightening. is there any reason besides superstition that we should sweat when applying that kind of torque to aluminum?

Bill Ball

Michael: It's a big fitting so the torque is distributed pretty well. I've torqued these before and they firm up nicely. You need that torque to crush the sealing ring properly - Oh, DEFINITELY do NOT reuse the sealing ring. I reuse the oil pan drain rings sometimes because they don't deform under the low plug torque, but the bypass, pressure relief and oil cooler line fittings are a different story. The ring gets squished a lot. You probably saw that, but I just wanted to make sure you have a new one handy.