The 'E' Type Forum

Hi All, I need to remove one of the domed nuts retaining the inlet camshaft cover to allow removal of the HT lead clip secured by one of these nuts. This is to allow replacement of the Leads. Can this nut simply be unscrewed and re screwed in place with no issue over torque settings etc or is there anything I need to be aware off?

Thanks

Yes, it will be OK provided you don't run the engine. Ideally you should re-torque the nut to spec.

Hi Dave many thanks for the fast response much appreciated. I assume you are referring to not running the engine until the nut is replaced. I don’t suppose you know the torque setting for these nuts, as I can’t seem to see it referenced in the Service manual?

Er, are we talking about cam-cover nuts (domed and chromed 1/4" UNF with 7/16" hex) or the big fat (and critical) cylinder- head nuts ?

Some of the pseudo-racing HT clamps made from Tufnol use the former, and most cars use the latter as well to carry the HT tube.

If it's the little cam-cover nuts then there is no figure given, it's a question of tightening them until nothing leaks, without over-tightening them such that they crack the cover casting.

If it's the head nuts, removing just one is not really very clever and nobody would encourage it, although you will probably get away with it - and the torque figures for these are in all the maintenance books.

Coming from my background of designing and building military and transport equipment, I struggle to agree with the practice of tightening by feel. Everything we design has to have toleranced torque values for every fastener.

When it comes to 'feel' everybody has a different idea of what feels right.

For a 1/4" UNF, I would start with 6 lb ft and see how that works. I would definitely not exceed 15 lb ft. You may be surprised by how low these torque figures 'feel' but don't be tempted to exceed them.

Regards

Thanks all for your help. It is the cam cover smaller domed chrome nuts I am referring to. I was aware of the criticality of the cylinder head nuts and just wanted to be sure there was no similar issue with the Cam cover nuts. In addition, unlike the head nuts I couldn't find any torque settings stated in any of the service/maintenance manuals.

I do them up to 4lbft, then I will tighten them to 7lbft if the cam cover leaks.

You need to be very careful of overtightening them as you can crack the cam cover under the nut and then it will leak.

Thanks Andrew - I will give those settings ago!