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LR bolt and screw thread codes

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Somewhere, and I cannot remember where, or even if it was on this forum, I have seen a list of LR thread codes that allow one to identify the length, diameter and tpi of bolts and screws.  I've spent quite some time searching this forum, with no success.  Please, can somebody point me to this table.  I'm at the stage of cleaning excess zinc from my galvanised bulkhead and need to retap various mounting points.  If I was a lot smarter I would have identified the details of all threaded holes before galvanising.😡😣

Mike

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I think BH is a Bolt Hex Head, SS Socket Screw (Allen screw) , FB Flanged Bolt.Bolt lengths are measure from under the head whereas screws include the head. SH is a screw, Hex head, ie machine screw, threaded all the way up whereas a bolt is assumed to have a smooth bit. Metric thread is normally the coarse thread.

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Even smarter to stuff them with silicone first!

 

Works quite well to stop zinc attaching.

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Thank you, both, for your replies.  That link, Red90, is just the dog's danglies.  It's not the one that I remember seeing, but it's even better, and now downloaded and a valued file in my Land Rover folder.  Thank you, again.

Mike

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On 1/18/2019 at 1:58 PM, Gazzar said:

Even smarter to stuff them with silicone first!

Doesn't the heat used in galvanising burn it off?

I used old bolts to protect the threads when I did mine chassis and heated them with a blow torch to remove them didn't need to properly tap anything.

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Silicone doesn't burn at all easily, you can even use it on exhaust manifolds...

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26 minutes ago, Bowie69 said:

Silicone doesn't burn at all easily, you can even use it on exhaust manifolds...

Make sure you use sensor-safe silicone if it's upwind of a lambda sensor - from intake to exhaust it will emit acid fumes as it cures and kill your sensor.

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7 hours ago, FridgeFreezer said:

Make sure you use sensor-safe silicone if it's upwind of a lambda sensor - from intake to exhaust it will emit acid fumes as it cures and kill your sensor.

I don't intend to use the knowledge anytime soon. for the exhaust I use grease as I have been told that it goes hard when heated.

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14 hours ago, Bowie69 said:

Silicone doesn't burn at all easily, you can even use it on exhaust manifolds...

The polymers in the silcone burn out at around 250 C.  The solids are left behind.  The high temperature versions have high solids, so that after burning out, there is still a lot of stuff remaining.  Zinc melts at 420 C, so it is ruined during the galvanizing.

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14 hours ago, FridgeFreezer said:

Make sure you use sensor-safe silicone if it's upwind of a lambda sensor - from intake to exhaust it will emit acid fumes as it cures and kill your sensor.

He was talking about filling the holes with silicone before galvanizing.  There will be no acids left after that is done!!

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1 hour ago, Red90 said:

He was talking about filling the holes with silicone before galvanizing.  There will be no acids left after that is done!!

And I was talking about exhaust manifolds, in response to Bowie's suggestion.

Zinc melts at 420C, EGT's can go way higher than that.

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Yup, EGTs on turbo diesels can easily be 800C, petrol being higher than that, I understand.

You can get special silicone sealants for the exhaust manifolds, I would guess they are all sensor safe given the locstion, but definitely worth checking!

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