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TR2/3/3A Heater tap locking nut

croz

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Has anyone used a lock nut to help secure the heater tap? If so, what size?
It would be great to know the size and thread before I start looking for one.
Cheers
 
Are you referring to where it threads into the head? I'm thinking that is a taper thread which would seem to make a locking nut impractical.

I do use Teflon tape on those threads as you cannot just tighten until it stops - you have to stop with a suitable orientation.
 
Possibly talking about the pipe that comes off the tap...we can wait for verification.

Cheers
Tush
 
Yep, I totally agree Geo.

Cheers
Tush
 
I am referring to the thread on the tap. There should be just enough threads for a slim lock nut.
I do use teflon tape but there is just a very slow seep of coolant as the tap is slightly loose.
It looks like a fine tread maybe 5/8 in.
thanks
 
Sorry. What I am looking for is a skinny "jam" nut. Looks like it might be 5/8" UNF. I won't know until the tap is on the bench.
 
I gave up on the jam nut and just cleaned and reinserted the tap, along with clear silicon adhesive/sealant.
After seating it as far as previously set, I very gingerly turned another 360 degrees. It is holding tight.
The tape does have tapered pipe threads. They were slightly deformed as far as it was tightened previously.
I believe that the softer threads on the tape deform to fit the steel threads of the head.
 
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