Torque Settings - (Aftermarket) Underbody Protection

[WHID]

I have no idea as to what the torque settings are for the bolts securing the underbody protection of my 2019 QE Sport.

Shortly after purchase, I had 3mm steel aftermarket (Boo's) protection fitted to the car. Given the extra weight, should these settings (whatever they be) be increased? (or decreased?)

I'm about to send the car off for it's 12 month/15K service and am feeling pretty wary about 'technicians' at the dealership stripping threads with their rattle guns, so I thought I might make it simple and remove the protection for them beforehand.

Upon re-installation, is there advice please as to what torque settings I should use? The same as the original, or something else?

Novice as I am, I'm becoming more and more anal with this stuff - sorry 'bout that. I'm probably subconsciously looking for an excuse to 'play' with my shiny new torque wrench.

Thank you . . . feelin' tight . . .

[JohnFromPerth]

I have Boos 3mm steel bash plates. I secure them with the bolts that held on the plastic splash guards. I put spring washers on the bolts and nip them up by hand until they are firm and compress the washers. Have had no trouble with bolts becoming loose. Don't do them up too tight as there needs to be some movement as the chassis flexes, otherwise the bolts will crack off. Some Locktight on the threads will give extra insurance.

[Keithyv]

I think you are massively overthinking it.

As above, use some medium duty thread locker if you must and do up 'tight' by hand with socket set.


I dunno, 50Nm is pretty tight

Manual does not even specify torque settings for stock plates.

http://faq.out-club.ru/download/pajero_iv/maintenance/Service_Manual_2008_2013/2013/51/html/M151101960046500ENG.HTM

Side steps for example are 60Nm, probably similar 'tightness' I guess is needed there as bash plates..

http://faq.out-club.ru/download/pajero_iv/maintenance/Service_Manual_2008_2013/2013/51/html/M151101150021500ENG.HTM

[old Jack]

Service Manual states 14Nm +/- 3Nm.

http://mmc-manuals.ru/manuals/pajero_sport_iii/online/Service_Manual/img/51/ACF00741AB00ENG.pdf

On my Challenger I replaced all the bolts with high tensile flange head bolts and Nord Lock washers as all other spring and vibration resistant washers failed to keep the bolts from coming loose on corrugated roads. I also believe that the bolts coming loose also increases the incidence of the mounting brackets cracking.

OJ.

[Dicko1]

As Jack says...use Nordlok washes and high tensile bolts. Not only do the bolts carry the weight of the plate but must hold it in position if plate is hit by rock or tree stump. Mine are just done up firmly by hand until they feel right. Many years of working on cars and motorbikes gives you a feel for a bolts tightness.

[Jasonmc73]

I have no idea as to what the torque settings are for the bolts securing the underbody protection of my 2019 QE Sport.

I'm about to send the car off for it's 12 month/15K service and am feeling pretty wary about 'technicians' at the dealership stripping threads with their rattle guns, so I thought I might make it simple and remove the protection for them beforehand.

Upon re-installation, is there advice please as to what torque settings I should use? The same as the original, or something else?

Novice as I am, I'm becoming more and more anal with this stuff - sorry 'bout that. I'm probably subconsciously looking for an excuse to 'play' with my shiny new torque wrench.

Thank you . . . feelin' tight . . .

Yeah mate that's a fair idea you have, the apprentice putting your bash plates back on after he's done your service

Follow service torques, it's the size of the bolt & the fixing that determines the torque required, not the plate you have fitted.

How many people do you hear have stuffed the threads? Quite a few so not such a bad idea you have.

[DibbyDibbyDJ]

As usual OJ is bang on the money with 15nm, Overtightening is a big problem. The standard bolts are no good on an impact driver and the threads stretch. Then when you unwind they strip out the captive nuts. Better bolts just move the problem on to the captive nuts, causing them to fail.


MQ/MR suffer badly as there are 2 long bolts that hold the rear plate on, these have spacers on them that if you go above specified torque they crush, and get jammed into the threads, and when you try to undo the bolts tend to twist slightly



I need a mig welder to service most utes with bash plates


As a dealer we report issues like this on the R/O to advise customer and get told "no, just put them back on".


I dont know if our reception staff dont give a sh1t or it really is the customer saying that.

[WHID]

Thanks chaps . . . all of you.

These posts answer my questions perfectly and reinforce my thinking too.

14 +/-3 Nm? . . . Wow!! My shiny new torque wrench doesn't go that low. Maybe a new one is in the offing . . . more expense *sigh*

I'm attempting to obviate having a 'horror story' such as those of which I have heard. Bad outcomes at the hands of 'technicians' are not all that uncommon - apparently.

Cheers . . . not as tight as I was . . .

[old Jack]

I also apply anti seize to these bolts.
When using Nord Lock washers you can feel when a fastener is tight enough.
Note, there is are wrong and right way to use Nord Lock washers so make sure you use them correctly.

OJ.

[Swede50]

I also apply anti seize to these bolts.
When using Nord Lock washers you can feel when a fastener is tight enough.
Note, there is are wrong and right way to use Nord Lock washers so make sure you use them correctly.

OJ.

https://www.youtube.com/watch?v=id973dHbATc&vl=en

And I thought I knew a bit about bolts and lock washers
Learning something new.
Guess the aircraft industry would use this sort of stuff a lot.
Perfect for off road

[WHID]

. . .I replaced all the bolts with high tensile flange head bolts and Nord Lock washers as all other spring and vibration resistant washers failed to keep the bolts from coming loose . . .

...use Nordlok washes and high tensile bolts. Not only do the bolts carry the weight of the plate but must hold it in position if plate is hit by rock or tree stump. Mine are just done up firmly by hand until they feel right.

As is usually the case, when I turn my hand to something it invariably becomes bigger than Texas and more complicated than a presidential vote in the same place.

Help me out please boys . . . I reckon I can access some M8 HT flange bolts and I have already purchased some Nord Lock washers. However, the washers as a standard size, won't do the job. Their outside diameter is too small to accommodate properly the flange on the bolts and the largish bolt-holes in the bash plates. I cannot buy larger ones at my source.

Can you tell me please, what size(?) washers you are using and where you accessed them? I would like to put these plates back on pronto.

By the way, I think the 'tech' at the service department was happy not to have to deal with the bash plates when accessing the underside of my Paj Sport.

Thanks again and cheers . . . becoming niftier with spanners, sockets and wrenches.

[old Jack]

Are Nord Lock Lard, large diameter washers too small?

https://www.unitedfasteners.com.au/washers-274/nord-lock-washers/large-od-washers

Remember there are different sides of Nord Lock washer so there is a correct way to Install them.

OJ.

[WHID]

Are Nord Lock Lard, large diameter washers too small? Remember there are different sides of Nord Lock washer so there is a correct way to Install them.

Thanks Jack, gotcha.

The penny would have to drop sooner or later. I was focussing on washers for 8mm bolts. With a flange it doesn't matter . . . 3/8 washers with an OD of 21mm will do the job admirably.

Orientation? Oh yes, have been devouring YouTube videos since your original post on this . . . I'm almost an expert. Ha ha ha!

Thanks again for your trouble. . . very much appreciated.

[old Jack]

Buy extra, they are reusable but I find after about 6 or so uses I can see wear on both the cam face and the serrated face, so I replace them.

OJ.

[Jasonmc73]

OJ do United Fasteners sell these in less than box full of 200?