fjmuurling Posted October 9, 2015 Report Share Posted October 9, 2015 Any opinions / experiences with using Nordlock washers for locking of the aerotight nuts for mounting the exhaust manifold to the Head?Freek Quote Esprit Freak Link to comment Share on other sites More sharing options...
Vulcan Grey Posted October 9, 2015 Report Share Posted October 9, 2015 Mine has the aerotight nuts and I was losing studs (still attached to the nuts...) all the time until I got the locking clips correctly applied.. Lotus hadn't bent very many of the clips, and they weren't close enough to the nuts to prevent them spinning. Quote Travis Vulcan Grey 89SE Link to comment Share on other sites More sharing options...
fjmuurling Posted October 9, 2015 Author Report Share Posted October 9, 2015 "Double" locking is required in order to prevent the nuts coming loose from the studs and to prevent the stuts coming out of the head with the nut still on.think I will go for the Nordlock Washers (easier mounting, no fiddling with tabs), If they fail I always can switch back to the tabs. Quote Esprit Freak Link to comment Share on other sites More sharing options...
Vulcan Grey Posted October 9, 2015 Report Share Posted October 9, 2015 Let us know how they work. FYI, there is not even enough room for a socket on some of those nuts, so make sure the Nord-Locks aren't larger diameter than the nut! Quote Travis Vulcan Grey 89SE Link to comment Share on other sites More sharing options...
ragingfool35 Posted October 10, 2015 Report Share Posted October 10, 2015 old school lesson of always tightening exhaust manifold bolts/nuts while hot, due to thermal expansion causing them to come loose. i would think that would hold true most especially for Nordlock.let us know how you fare Quote chris90SEjust because I don't CARE doesn't mean I don't UNDERDSTAND Link to comment Share on other sites More sharing options...
Chillidoggy Posted October 10, 2015 Report Share Posted October 10, 2015 I used K-nuts when I replaced my old manifold with the Alunox one. I fitted them cold and haven't had any of them coming loose. Quote Margate Exotics. Link to comment Share on other sites More sharing options...
naasaa Posted October 10, 2015 Report Share Posted October 10, 2015 I used nordlock washers on my. Havent had any issues.Used them on my Volvo T5 in the past. They had a notorious problem with studs coming loose.Nordlock are standards on large turbocharger nozzle rings. These you cant tightening when hot.Lars Quote Link to comment Share on other sites More sharing options...
lotus4s Posted October 10, 2015 Report Share Posted October 10, 2015 I've used the Nordlock washers on the exhaust manifold in several Esprits and never had an issue with them coming loose. Sure beats bending and unbending the locking tabs. 2 Quote 1995 S4s Link to comment Share on other sites More sharing options...
ragingfool35 Posted October 10, 2015 Report Share Posted October 10, 2015 good to know Quote chris90SEjust because I don't CARE doesn't mean I don't UNDERDSTAND Link to comment Share on other sites More sharing options...
glynherron Posted October 10, 2015 Report Share Posted October 10, 2015 What is the best adhesive available in the UK to fix the studs to the head or is it not required? Quote Link to comment Share on other sites More sharing options...
fjmuurling Posted October 10, 2015 Author Report Share Posted October 10, 2015 AFAIK it is not required, aerotight nuts with locking plates / Nordlock washers do the job.I will be using Nordlock washers Quote Esprit Freak Link to comment Share on other sites More sharing options...
sailorbob Posted October 11, 2015 Report Share Posted October 11, 2015 The workshop manual states Permabond A025 High Temperature Sealant is to used on the exhaust manifold studs. Loctite 272 is similar. Quote Link to comment Share on other sites More sharing options...
glynherron Posted October 11, 2015 Report Share Posted October 11, 2015 Thanks Guys Quote Link to comment Share on other sites More sharing options...
Chillidoggy Posted October 12, 2015 Report Share Posted October 12, 2015 I know one thing: I tried unwinding my cylinder head exhaust studs, and gave in when I was sure they would shear. Whatever they're in with, it must be damn good stuff. Quote Margate Exotics. Link to comment Share on other sites More sharing options...
sailorbob Posted October 12, 2015 Report Share Posted October 12, 2015 There are high temperature threadlockers with much higher shear strengths than the Permabond A025 and. Loctite 272, maybe someone's used one of those in the past. Quote Link to comment Share on other sites More sharing options...
Loose Cannon Posted October 12, 2015 Report Share Posted October 12, 2015 Is it recommended to replace the studs when fitting the new stainless manifold? Would differential corrosion be a problem if the existing ones are left on?And worst case scenario is it an engine out job if one shears? Quote In the garage no-one can hear you scream Link to comment Share on other sites More sharing options...
Chillidoggy Posted October 12, 2015 Report Share Posted October 12, 2015 The original Lotus studs are stainless. Therefore no corrosion issues.If studs shear in situ, the cylinder head has to come off to fix it. I recall Sparky had to do that when he fitted his new Alunox manifold. Quote Margate Exotics. Link to comment Share on other sites More sharing options...
ajheath Posted October 12, 2015 Report Share Posted October 12, 2015 Funny this should come up. My 2 year old Alunox manifold developed a blow last week, and i feared the worse, that a weld had gone. jacked the car up yesterday and crawled under for a look. Hey presto front port has one stud missing and one with the stud still in but the nut gone. I used the Nordlock type nuts that came with the manifold but obviously didnt fasten them up tight enough. Lesson leanred Quote Link to comment Share on other sites More sharing options...
fjmuurling Posted October 12, 2015 Author Report Share Posted October 12, 2015 The (mine) Alunox Manifold came with Flange Nuts and no Nordlock Washers. Flange Nut example: Nordlock Washer (1 washer is made of 2 parts) example: Quote Esprit Freak Link to comment Share on other sites More sharing options...
Loose Cannon Posted October 12, 2015 Report Share Posted October 12, 2015 Which is better? Quote In the garage no-one can hear you scream Link to comment Share on other sites More sharing options...
fjmuurling Posted October 12, 2015 Author Report Share Posted October 12, 2015 You need "double" locking, so special locking (aerotight) nuts in combination with tabs or locking (nordlock) washers. Quote Esprit Freak Link to comment Share on other sites More sharing options...
ajheath Posted October 22, 2015 Report Share Posted October 22, 2015 The (mine) Alunox Manifold came with Flange Nuts and no Nordlock Washers. Flange Nut example: Nordlock Washer (1 washer is made of 2 parts) example: Ahh, I thought the flange nuts were nordlock, but now I see what you mean, might put nordlock washers on and see how I go. Quote Link to comment Share on other sites More sharing options...
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