oil drainbolt froze? new 08

[El Toro]

There's a flaw in your bolt elongation theory. As a machinest and a mechanic I can say without a doupt that the aluminum threads will pull out of the pan before the steel bolt elongates. The bolt elongation thing refers to head bolts generaly, and those are steel bolts threaded into steel blocks. If you use the factory oil drain bolt specs, you will stress the threads and eventually pull them out completely.

I'm not going to get into a pissing contest beyond this post... you can have the last word if you like.

Regarding the idea that the specified torque will eventually cause the threads to fail, I could do the calculation, but I'm not interested enough to do it. The spec is reasonable, and it gives a good seal.

I was a mechanic/machinist many years ago. I know the friction that exists between the engineering folks and the ones who think the engineers are idiots.

Everyone tends to evaluate the world according to an algorithm that puts themselves on top. Machinists and engineers are both guilty. I got nuthin' to add, except that most of the time with Japanese or German bikes, the specs will be pretty solid and well thought out. Now the Italians or the Americans are another story.... :lol:

 

[charismaticmegafauna]

Everyone tends to evaluate the world according to an algorithm that puts themselves on top.

Can I get an ... Amen?

 

[Constant Mesh]

The quoted torque values assume components have clean, dry threads. Don't know how one could ever get all the oil off the engine drain bolt and oil pan threads. The only time this bolt has dry threads is when it's first installed at the factory before the oil is poured in.

The drain bolt has 14mm threads. The typical torque for a 14mm steel bolt and nut would be 61 ft-lbs.

 

[Mackeroni]

Hi guys, Tried to change oil tonight, pretty simple access. Tupperware removal basic but...the oil drain thingy; I can not break the bolt. I'm afraid to put any more pressue on this thing. I'm a pretty big boy and can not budge this bolt. Any ideas. How bad to just change the filter and let the dealer **** with this at 5-600 mile service? BTW, I only had 1 mile on the bike when I took delivery Friday night. Thanks bes
first ride experiences to come if anyones cares.............

I know this is too late for you but I'm shopping for an '08 and am waiting for D&H to get order confrmation from Yamaha. I have the forum's checklist for delivery and have heard that D&H is pretty good about taking you through the list and then some. If my deal goes through I plan to ask them to loosen the bolt and torque to 30 lbs or so before I take delivery. This seems so well documented that I can't understand why others don't do this. Maybe others can clue me in. Is it the crush gasket? That you'd HAVE to replace that even if you just loosened the drain bolt a bit and then resnugged? That may be the case. Actually, the first change headache might be worth having the dealer remove and refit both plug and crush gasket before taking delivery. Catch the oil and put it back in after changing the gasket and reinstalling the bolt.

Interested if others have done this or can alert me if it is stupid.

Lee

Lee... Nick at D&H should be able to loosen and re-torque the drain bolt for you. (Wish I had thought to ask him to do this.) His advice to me was it is generally okay to reuse crush washers up to 4 times as long as they are intact... in other words, as long as they are not cracked and have not been obviously leaking.

 

[LSUBOY]

When you do get it off torque it to 25 ft. lbs. That's all you need and as with the other guys I feel that 29 or 30 IS too much.

 

[Bull]

When you do get it off torque it to 25 ft. lbs. That's all you need and as with the other guys I feel that 29 or 30 IS too much.

If you give torque advice as well as you shave, I hope you're not offended if I don't follow your advice!



[just kiddin man - I agree with you wholeheartedly]

 

[v65]

If my deal goes through I plan to ask them to loosen the bolt and torque to 30 lbs or so before I take delivery. This seems so well documented that I can't understand why others don't do this.

Several people have stripped their pans going to 30 ft/lbs. This is a topic that has been discussed thoroughly over the years, my opinion is leave the torque wrench out of the oil change process - crush the washer with a 3/8 drive ratchet and ride it. Your mileage may vary.

EDIT: oops, I see several others have already expressed the similar opinions. Don't know how I missed those. oster_oops:

 

[Spook]

Is there something I am missing? I have been changing oil on my motorcycles for over 40 years and have never had a torque wrench come into play. Never had a plug fall out or it leak ether. Oh and no stripped threads. Are some people just anal?

 

[ionbeam]

I'm always amazed how the factory gorilla is so skillful that he/she can torque the oil pan bolt to 120 ft/lb without stripping it, yet we pull the treads out with less than 30 ft/lbs. C. Mesh is correct about dry vs oily torque values, but even after applying a dry/wet correction factor of 30-40% to the factory torque spec it is still a mystery how the bolt could be so tight. I'm thinking that the designing engineer intended to ask for anti-seize to be used, but inadvertently specified locktite green.

 

[keithaba]

Someone said they stripped their drain plug when they retorqued. I can't see it. It sounds more like cross threading, and it was nice of Yamaha to make it good anyway. As I watched my crush washer collapse on the retorque, and as I listened for the click on the wrench, it all seemed very reasonable and normal. Nothing whacky.

It is a well documented issue. Nothing to do with cross threading.

It seems that the torque value reccomended in the service manual is for a dry bolt.

 

[big ears]

Me thinks if someone always needs a torque wrench they may be numsensed or very inexperinced in mechanical things.

 

[Constant Mesh]

This issue is all a function of the crush washer and the thread pitch (distance between consecutive threads) on the bolt. All you're trying do is tighten the bolt enough to properly crush the washer. Very similar to installing a spark plug.

If a new washer is 1/8" thick and a crushed washer is 1/16" thick then you must turn the bolt just enough to move 1/16" into the oil pan after the washer is finger tight snug.

If the bolt threads are 1/16" apart then one additional turn after finger tight would be just right to crush the washer to its final 1/16" thickness.

It might be simpler to note how far you've turned the bolt after it's finger tight and ignore the torque required.