Drain Plug Torque / sealing washers

[skids]

Oil plugs are not really bolts are they? I mean, they have a broader head to accomadate a sealing surface for the washer.

[James England]

Always extra cautious with spark plugs too. To me drain plugs and spark plugs are two items that are easy to mess up and hard to repair.

Jeff

Agreed! I've never ever used a torque wrench on a spark plug. One thing, some torque wrenches are awful...you know, the ones with a big needle and a fan-shaped thing with gradations on it, near the handle. They aren't very accurate and I can't imagine anything worse than merrily tightening up spark plugs or drain plugs with an inaccurate torque wrench, then feeling that sickening, suddenly easy twist as the inaccessible plug threads detach themselves from the head

Re drain plugs... why not wrap some PTFE tape around the threads of the plug? That will work.

[jetmechmarty]

Agreed! I've never ever used a torque wrench on a spark plug. One thing, some torque wrenches are awful...you know, the ones with a big needle and a fan-shaped thing with gradations on it, near the handle. They aren't very accurate and I can't imagine anything worse than merrily tightening up spark plugs or drain plugs with an inaccurate torque wrench, then feeling that sickening, suddenly easy twist as the inaccessible plug threads detach themselves from the head

Your elbow has to have some calibration to detect a failed torque wrench. I put the drain plugs to 23 ft lbs (lube tq). It felt right when I did it and it's not leaking.

[James England]

Your elbow has to have some calibration to detect a failed torque wrench.

I'm not saying that. I mean, I trust my hand/arm more than a possibly dodgy torque wrench. It would be too easy to give it some welly with a torque wrench without knowing how tight it really is, because the lever is so long on them. With a spanner from a socket set, I can feel when a drain plug is sitting tight without being in danger of over tight. Same goes for the spark plugs.

[jetmechmarty]

If the spark plugs have a new washer, the proper torque is seated plus one half turn. For reinstallation with a crushed washer it's seated plus one quarter turn. I don't remember where or when I learned that.

[James England]

If the spark plugs have a new washer, the proper torque is seated plus one half turn. For reinstallation with a crushed washer it's seated plus one quarter turn. I don't remember where or when I learned that.

So we don't need a torque wrench!

Yes, you're correct. I read that somewhere too. I'd trust that method the most...

[cywelchjr]

If the spark plugs have a new washer, the proper torque is seated plus one half turn. For reinstallation with a crushed washer it's seated plus one quarter turn. I don't remember where or when I learned that.

The FSM states the torque for the spark plugs as 14.5 ft/lbs. I prefer to use my click torque wrench, using whichever one is best suited to the torque range of a given fastener or part. I would rather trust a precision tool rather than trust my inaccurate arm, and I've never seen or heard the 1/2 turn 1/4 turn stuff, and I'm not sure that works with the spec being different for iron heads and aluminum heads, I'll stick with what the manual says.

[WMarshy]

Correcto, the Service Manual Page 7-10 has two columns for the General Torque Specifications. Column A is for mm "Distances across flats". Column B is for mm "Outside thread diameter. ...Jeff

Man that table would be handy to have in the tech tips I tell ya. I cant count how many times I have been following the manual and have been like WTF where is that torque spec! I usually end up doing a quick word search here and finding it.

...I prefer to use my click torque wrench, using whichever one is best suited to the torque range of a given fastener or part. I would rather trust a precision tool rather than trust my inaccurate arm...

I have heard from mechanics (not vehicle mechanics, the ones in the power plant where I work) about receiving training on how to use "elbow torque". From what they were saying, the elbow is highly unreliable.

[James England]

I'll stick with what the manual says.

Not always advisable, given the inaccuracy of some manuals... like the Clymers. Have a look at the distorted swingarm threads... they stuck with what the manual said, used a torque wrench and found the manual was so wrong re the torque figure that the swingarms were distorting. Had the typo been on the spark plug torque and not the swingarm bolt torque, you'd have stripped your plug threads in the head, without a doubt, and not one click from your wrench to warn you. Following a manual is all very well but none of them are 100% accurate and the Clymers is laughably wrong. (although not such a laugh if you've done what it says and find your threads/bolts/nuts have stripped)

[jetmechmarty]

Not always advisable, given the inaccuracy of some manuals... like the Clymers. Have a look at the distorted swingarm threads... they stuck with what the manual said, used a torque wrench and found the manual was so wrong re the torque figure that the swingarms were distorting. Had the typo been on the spark plug torque and not the swingarm bolt torque, you'd have stripped your plug threads in the head, without a doubt, and not one click from your wrench to warn you. Following a manual is all very well but none of them are 100% accurate and the Clymers is laughably wrong. (although not such a laugh if you've done what it says and find your threads/bolts/nuts have stripped)

There are torque standards, but most of us don't know them. If one has no experience, how would he know how much torque to apply to a spark plug? We trust the book. Shame on them when it's wrong.

[CaptonZap]

Not always advisable, given the inaccuracy of some manuals... like the Clymers. Have a look at the distorted swingarm threads... they stuck with what the manual said, used a torque wrench and found the manual was so wrong re the torque figure that the swingarms were distorting. Had the typo been on the spark plug torque and not the swingarm bolt torque, you'd have stripped your plug threads in the head, without a doubt, and not one click from your wrench to warn you. Following a manual is all very well but none of them are 100% accurate and the Clymers is laughably wrong. (although not such a laugh if you've done what it says and find your threads/bolts/nuts have stripped)

James, look at it this way, concerning the Clymer manual.
How many people who bought the bikes, actually work on them, and of those, how many actually checked the swing arm bearing? EVER?
Now, had the torque for the plugs have been wrong, after a few stripped heads, with commensurate law suits, the next printing would have been amended to reflect the proper value.
As the math teachers told us, back when calculators were first coming in to popular use, check the answer and see if it is reasonable. 47 foot lbs on an internal wrenching bolt with a 6mm wrench? (Swing arm pivot). Doesn't sound right.
A bit of common sense can forstall a lot of problems, if used before the act.
Actually, the misprint in the manual underscores one of the faults I find in the metric system. It is too easy to transpose a decimal while transcribing.
Inches to foot llbs? A decimal shift doesn't doesn't mean much, if anything.
"Course then, you get into base 12 numbering systems, and Lord knows how many mistakes can come out of that conversion. CZ

[James England]

A bit of common sense can forstall a lot of problems, if used before the act.

Looking at this forum, loads of people buy these bikes and work on them. I think in general that people who buy a manual are at least thinking about working on the bike themselves.

It's not a case of "common sense"... it's about knowledge and experience. You have mechanical experience, as do I, and therefore can use your judgement but torque settings for a spark plug don't fall into the "common sense" category... certainly not for an aspiring newbie. Most people learn the hard way re stripping threads, skinning knuckles, dropping bits and losing them etc.

The point is, two people on this very forum have done that thing with the swingarm, as a direct result of inaccuracies in the Clymer manual. Do they therefore lack "common sense"? I don't think so. They "stuck with what the manual says" and unfortunately the manual was wrong. And that's a manual which doesn't use the decimal system at all. It's good 'ole foot pounds and it's incorrect.

All I'm saying is, don't treat a manual as if it's the gospel truth. Don't "stick with what the manual says" in fact.

[crazy steve]

There's no 'easy' fix for this... as James said, it's mostly about experience. I've owned enough different vehicles over the years that I've seen multiple solutions to the same problems so sometime will ignore the 'factory' solution in favor of another procedure that works better IMO. Does that make me 'wrong'? To some people, maybe, but if you get to the same place it shouldn't matter.

I haven't seen a factory manual that's 100% correct yet. Some are better than others, I'd rate the Yamaha manuals as only mediocre compared to most; the Japanese manuals have never been known for their clarity. The aftermarket ones are rarely better except in their command of the english language.

As to torque specs, Yamaha did poor job of noting these. Yes, the specs are all there if you know where/how to look, but it's less than clear as to which are important and which aren't. Clymer attempted to address this by inserting the specs in the unit repair sections, but failed to get all the numbers right. Personally, anything to do with the motor/trans/chassis is always torqued to factory spec; I won't use the Clymer (or any other aftermarket manual) for this unless that's the only thing available. Given that forum member CatatonicBug offers a free download of the factory manual on his website, there's no reason a XS owner can't have the right numbers.

And Jeff talks about those 'generic' torque charts that you find in most manuals; be very careful of those. These don't take into account bolt grade, the material you're threading into, specialty bolts, or specific requirements on a particular assembly.

A few years ago I assembled (from easily available internet sources) my own 'bolt guide'. Printed out and put into a bound folder, I refer to this regularly. Containing torque specs for both standard and metric fasteners, it also has specs noting different materials, i.e. steel bolt grades (grades 1, 5, and 8 and metric equivilents) as well as aluminum, brass, and stainless. I had this in a file folder, but it didn't survive my last computer crash or I'd offer it. This also has drill sizes and threading/tapping info. Most of the info I got here: http://www.boltdepot.com/fastener-information/ , the rest is available from multiple places.

[James England]

A few years ago I assembled (from easily available internet sources) my own 'bolt guide'. Printed out and put into a bound folder, I refer to this regularly. Containing torque specs for both standard and metric fasteners, it also has specs noting different materials, i.e. steel bolt grades (grades 1, 5, and 8 and metric equivilents) as well as aluminum, brass, and stainless. I had this in a file folder, but it didn't survive my last computer crash or I'd offer it. [/url] , the rest is available from multiple places.

Do you have a scanner? And spare time?

[DAVINCI]

Here are a couple of pages from my FSM

The general torque values:



And the MAJOR error (or at least the one I've found so far) Don't ask how I discovered this error, suffice to say it was a bad day