Torque on oil drain bolt

[mfisher1967]

I have started using a torque wrench to install the oil pan drain bolt, which is set to 29 fl/lbs. I am afraid that I will strip the threads on the oil pan if I attempt to do this using a ratchet because I tend to be a little heavy handed when it comes to tightening nuts and bolts. I am considering installing a Fumoto drain valve to do away with this task altogether.

Has anyone ever stripped out the threads on their oil pan? How much torque would it take to actually do this?

I am sure that some quick oil change places use powerful air tools to remove/install this bolt, so perhaps my fears are unfounded.

[ctobio]

Originally posted by mfisher1967

I am sure that some quick oil change places use powerful air tools to remove/install this bolt, so perhaps my fears are unfounded.

They would be immensely stupid to do so. I would guesstimate that it would take well in excess of 50 ft-lbs of torque to strip the threads.

[iivtecracerii]

i tighten till my biological torque wrench says its tight enough.

[N_Jay]

Originally posted by mfisher1967
I have started using a torque wrench to install the oil pan drain bolt, which is set to 29 fl/lbs. I am afraid that I will strip the threads on the oil pan if I attempt to do this using a ratchet because I tend to be a little heavy handed when it comes to tightening nuts and bolts. I am considering installing a Fumoto drain valve to do away with this task altogether.

Has anyone ever stripped out the threads on their oil pan? How much torque would it take to actually do this?

I am sure that some quick oil change places use powerful air tools to remove/install this bolt, so perhaps my fears are unfounded.

Use the torque wrench a few times and pay attention to the force needed.

Then you will get a feel for what is right.

Most bolts don't need near the force most people apply.

[colorider]

Originally posted by mfisher1967
I have started using a torque wrench to install the oil pan drain bolt, which is set to 29 fl/lbs. I am afraid that I will strip the threads on the oil pan if I attempt to do this using a ratchet because I tend to be a little heavy handed when it comes to tightening nuts and bolts. I am considering installing a Fumoto drain valve to do away with this task altogether.

Has anyone ever stripped out the threads on their oil pan? How much torque would it take to actually do this?

I am sure that some quick oil change places use powerful air tools to remove/install this bolt, so perhaps my fears are unfounded.

The Fumoto drain valve is a good way to go. I used them for many years when I was driving LOTS of miles and making frequent oil changes. I have not personally stripped the oil pan threads on any vehicle. but know people who have. In each case it was an aluminum alloy pan on a motorcycle.

Good luck!

[colorider]

Originally posted by N_Jay


Use the torque wrench a few times and pay attention to the force needed.

Then you will get a feel for what is right.

The only problem with this is the typical torque wrench has a much longer handle than the typical ratchet handle and it will be difficult to compare the two.

[N_Jay]

Originally posted by colorider


The only problem with this is the typical torque wrench has a much longer handle than the typical ratchet handle and it will be difficult to compare the two.

We are not talking about fine adjustments.

It should still give you a decent idea of how much is too much.

[colorider]

Originally posted by N_Jay


We are not talking about fine adjustments.

It should still give you a decent idea of how much is too much.

The point is that the same amount of leverage on a 18" handle will yield much different torque on a bolt than on a 12" handle. If the OP is concerned with the torque of the bolt, he should continue to use a torque wrench and not rely on what it "feels" like with a torque wrench compared to a shorter ratchet handle. Apples and oranges when you change the handle length.

[N_Jay]

Originally posted by colorider


The point is that the same amount of leverage on a 18" handle will yield much different torque on a bolt than on a 12" handle. If the OP is concerned with the torque of the bolt, he should continue to use a torque wrench and not rely on what it "feels" like with a torque wrench compared to a shorter ratchet handle. Apples and oranges when you change the handle length.

I would think the average person could figure out how to be close enough without too much worry.

[colorider]

Originally posted by N_Jay


I would think the average person could figure out how to be close enough without too much worry.

If you go back and read, the OP asked the question because he WAS concerned about applying too much torque. I'm guessing he is very average, just like the rest of us.

[N_Jay]

Originally posted by colorider


If you go back and read, the OP asked the question because he WAS concerned about applying too much torque. I'm guessing he is very average, just like the rest of us.

I guess, I have more faith in "Average" people than you do.

[colorider]

Originally posted by N_Jay


I guess, I have more faith in "Average" people than you do.

You chose the word "average". I was simply trying to answer the question.

[N_Jay]

Originally posted by colorider



You chose the word "average". I was simply trying to answer the question.

Practice does not always make perfect, but often makes "good enough"!

[colorider]

Originally posted by N_Jay


Practice does not always make perfect, but often makes "good enough"!

I'm sure there is a point and not just your wanting to have the last say.

But, I guess you cannot acknowledge or accept when someone posts clarification that may be a little different than your thinking.

Oh well........

[whizmo]

My experience is that torque specs for oil drain bolts tend to be too high for two reasons: 1) many oil pans are "slotted" on one side of the drain boss to encourage more complete draining which tends to weaken the boss and make it spread as you approach the rated torque; and 2) most torque ratings are a function of bolt size and tend to assume dry/clean thread; typically a drain bolt is very well lubricated.

Both of these factors mean that the margin of safety for you to over-torque a bolt in this application are less than normal. Also keep in mind that torque wrenches are typically not calibrated very well and 30 ft-lb may actually be 35 or 40. Finally, drain bolts are steel and pans are aluminum and you know who will win.

The fact that tens of companies make oversize/self-tapping drain bolts to remedy the problem of people stripping them indicates to me that it's not that tough to do. Although I've never done it, I once had an R1 motorcycle which was in for a recall and since it needed an oil change, I had the shop do the change. Yep, their trained mechanics stripped it and they had to ante up with a new oil pan.

I've changed oil hundreds of times on a variety of vehicles without either one loosening in service or stripping, so I stick with my own calibrated feel for the wrench and how the bolt tightens up, but if you use a torque wrench, I'd tend to err on the low side a bit.

- Mark