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MG MGB Technical - Kingpin Swivel Nylock?

The refurbished ones come without the cotter pin hole and castle nut. When I torque the new Nylock (no washer)to the recommended 60 ft.lbs the swivel is way too tight. Without the road wheels on, should the swivel rotate with ease or take both hands and arms to move it? When the thrust washers and end play and torque are correct, how hard should it be to rotate the assembly? Mine is way too tight at around 30 ft. lbs.
R Stegs

If end play is OK, torque on the nut should not affect it. Should move very easily.
Art Pearse

With the front wheels off the ground you should be able to spin the steering wheel from lock to lock with a finger-tip. Wheels fitted or not should be irrelevant. The king-pin is shimmed for the correct end-float with selective washers, if it tightens up as you tighten the nut then the shimming is incorrect.
Paul Hunt

Proper torquing of the kingpin nut, with a Nyloc nut, is next to impossible as the added amount of resistance of the Nyloc nut renders the torque figures highly inaccurate. Tightening the nut to the point where everything moves smoothly and without binding is your main goal. RAY
rjm RAY

In addition to what Ray has noted, I would note that I had the original castellated nut hardness tested, then the current nyloc nut. The current nuts are quite a bit softer than the original type of nut and may not be capable of accepting the torque specified for this part in the factory workshop manual.

Les
Les Bengtson

RJM Ray, no this is not correct. Paul Hunt lays this out clearly in that shims must be fitted and then the nut tightened to the correct torque. It's the shims that determine the stiffness of the swivel pin and not the torque on the nut
Iain MacKintosh

Thanks guys. I snugged them down with the nylock and have a lot more free swivel now. I drilled through the nuts and shafts and put safety cotters in just in case. The road test went well and I have a bit of final toe in adjustment to do and I am good to go. Cheers!
R Stegs

R-
Nylock nuts are for resisting rotation under conditions of vibration, not for under conditions of repeated torsion. No way I'd trust a nylock nut to never loosen in an application like this. The whole idea of using a castle nut locked by a cotter pin is to prevent the castle nut from ever rotating off of the kingpin.
Stephen Strange

Nevertheless Nyloc or stiff-nuts are usually fitted in this location and I've not had a problem with them.

It's certainly not the same with the damper link pin, which although correct with the hole for the split-pin is often supplied with a Nyloc. The Nyloc is too tall so the nylon insert barely engages any threads, when at least three thread should be clear. This pin also needs a lower profile castellated nut than would be 'standard' for that size thread for the split pin to be fitted.
Paul Hunt

"I drilled through the nuts and shafts and put safety cotters in just in case"
R Stegs

You shouldn't have to.
Paul Hunt

This thread was discussed between 23/06/2013 and 29/06/2013

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