Sump Plug

[mpgscott]

Well did the first service for me on the bike tonight, bike has only done 5800 miles in just over 3 years most of which has been in last few months under my ownership.

Anyway tonight i did the oil and filter gearbox and final drive and checked the valve clearences so all good. However when i refitted the sump plug with new crush washer when i went to torque to 32nm then i felt the horrible feeling of close to over doing it. I had checked the torque wrench against a calibrated unit at work so its all good. Now the question is does the crush washer give a feeling when new like this?? Most of the time in the past doing many oil changes on the car i normally simply re-use the old crush washer so its a new one to me fitting a new washer. I didnt go to the 32nm i didnt want to risk it. Checked with my smaller torque guage that goes upto 24nm and its more than this as it is.

Just wanting to see what folk think?

 

[AberdeenAngus]

Torque wrench on a sump plug.......oh my!

 

[mpgscott]

Aye, according to the destructions its initial to 23nm then to 32nm, i however have opted for tight...

 

[Delboy777]

Torque wrench ???? use your own sense of feel that's what I do except on wheels etc.

 

[(RIP) Bin Ridin]

I always use a torque wrench on any serious bolt where possible. The sump plug and washer do give a worrying soggy feel, but if you have not gone past 32NM, it should be fine.

 

[mirboo72]

I did some damage on the gearbox sump and worried it would be a problem the next service..however when I unscrewed it the threads repaired it self and managed to tighten it to spec again.

 

[mpgscott]

Yeh its that soggy feel, i havent gone past 32NM and took it out for a wee blast today and checked no leaks.

 

[Smug]

That feel is probably just the crush washer crushing.

 

[DGB]

To the people deriding users of torque wrenches, if you've years of experience you may have some repeatability in your "calibrated" wrist but how close you get to the recommended torque value is anyone's guess. If you have a torque wrench use it, if you don't good luck but why scoff at those who choose to use them.

 

[UpgradeAl]

To the people deriding users of torque wrenches, if you've years of experience you may have some repeatability in your "calibrated" wrist but how close you get to the recommended torque value is anyone's guess. If you have a torque wrench use it, if you don't good luck but why scoff at those who choose to use them.

Totally agree. Otherwise why would they exist??

 

[flatdog]

Spanners and torque wrenches. PAH,

I'm that 'ard I just use my fingers.

 

[trainman]

i subscribe to the school of thought that says the figures quoted are for dry components, its very difficult to get a bone dry sump plate hole thread, any oil on the hole or bolt will reduce friction and increase the load you apply for a given 'dry' torque,
I do it by feel but as has been said you need to do what makes you feel best

 

[JJH]

I do it by feel for sump bolts and such but not components like cylinder heads and castings Jjh ps I only do it by feel if the lights are out. !!!!!

 

[Bendy toy]

i subscribe to the school of thought that says the figures quoted are for dry components, its very difficult to get a bone dry sump plate hole thread, any oil on the hole or bolt will reduce friction and increase the load you apply for a given 'dry' torque,
I do it by feel but as has been said you need to do what makes you feel best

I agree. It's not hard to feel when a fastener is tight enough.
I always torque the special stuff cylinder heads etc and bolts done tighter or looser than you'd expect.
But I've stripped more ordinary threads using a torque wrench than doing them by feel. So far nothing has fallen off because I set it too loose.
I also use copper anti seize anywhere corrosion is a risk (dear purists - not head bolts etc). It avoids electrolytic corrosion but can affect the required torque setting. Tightening by feel avoids the problem.
I have a 1/2" Norbar that gets used on special stuff. I also have 3/8" and 1/4" but almost never use them.

 

[Damien]

I agree. It's not hard to feel when a fastener is tight enough.
I always torque the special stuff cylinder heads etc and bolts done tighter or looser than you'd expect.
But I've stripped more ordinary threads using a torque wrench than doing them by feel. So far nothing has fallen off because I set it too loose.
I also use copper anti seize anywhere corrosion is a risk (dear purists - not head bolts etc). It avoids electrolytic corrosion but can affect the required torque setting. Tightening by feel avoids the problem.
I have a 1/2" Norbar that gets used on special stuff. I also have 3/8" and 1/4" but almost never use them.

Is your post the result of professional training or personal experience?

 

[UpgradeAl]

.
But I've stripped more ordinary threads using a torque wrench than doing them by feel. So far nothing has fallen off because I set it too loose.

Do you actually know how to set a torque wrench??

 

[mpgscott]

My main question was answered by Smug its likely just the crush washer working, like i said i normally re-use the one fitted so i have never really experienced the feel of a new crush washer so few thats good news.

I dont do mechanics as a day job im a weekend or even 12month mechanic so dont have a wealth of everyday experience, with this in mind i will always use my calibrated torque wrench (calibrated against a known unit at work) I do however know when something is not just right and know to stop thankfully.

Cheers
Mark

 

[Smug]

If you can tighten the bolt/nut with a ring spanner then the length of the spanner is the clue to how tight it has to be.

When a socket wrench is used then the spanner length stays the same although the socket size can vary considerably. A DIY mechanic would struggle to appreciate how tight is right.

 

[MattW]

i subscribe to the school of thought that says the figures quoted are for dry components, its very difficult to get a bone dry sump plate hole thread, any oil on the hole or bolt will reduce friction and increase the load you apply for a given 'dry' torque,
I do it by feel but as has been said you need to do what makes you feel best

The torque figure on the various oil retaining plugs are calculated for an oiled thread.

The feeling that the OP just experienced is almost certainly the annealed crush washer doing its job and 'crushing'. The first time you experience it, it is indeed a horrible thing as it's just the same feeling you get as threads in alloy go plastic just before they strip.

Despite what the various nay-sayers in this thread have to say, I'd say if you've got a torque wrench then use it - it's what they're for, especially if you haven't developed a 'feel' for fasteners into alloy.

However, don't be tempted to use the quoted torque figures for an old, already used washer as it will already have crushed and work hardened.

 

[Smug]

I must be a tight bugger because I keep all the old copper washers off customers cars and when I get enough of them I get the blow torch out and anneal them. Cherry red and dropped into a bucket of water.