Author Topic: Radiator Bleed screw  (Read 969 times)

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Offline Lotusjps

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Radiator Bleed screw
« on: Wednesday,July 11, 2018, 03:40:59 PM »
So getting my engine all back together after a complete rebuild, I went to bleed the air from the radiator and the top of the bleed screw broke off.  It appears to have broke in the middle of the screw, which is a little baffling.  I think I can get the remainder out without much work, though no clue were to source a replacement.  Messing with my thread dies with portion of the screw that came out, seems to be a 12-24 thread (or at least as close to it as I can tell), though my be metric since the hex part seems to be.  The parts manual appears to show a petcock valve rather than a bleed screw.  I'm curious if anyone else has a radiator with a bleed screw (small brass screw with a hole through the center)?
« Last Edit: Wednesday,July 11, 2018, 04:32:40 PM by Lotusjps »

Offline LotusJoe

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Re: Radiator Bleed screw
« Reply #1 on: Thursday,July 12, 2018, 11:59:46 AM »
Any good local radiator shop can repair it at minimal cost.
Joe Irwin
3927R TC Special
(The Classic Barn Find)


Offline Grumblebuns

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Re: Radiator Bleed screw
« Reply #2 on: Thursday,July 12, 2018, 02:45:26 PM »
Not definitive but the three TCSs in my possession/sold have bleed screws like you are describing. The three S2s that are in my possession/sold have bleeder petcocks. 

Offline Lotusjps

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Re: Radiator Bleed screw
« Reply #3 on: Thursday,July 12, 2018, 04:06:33 PM »
Thanks for the info!  Now it's the challenge of tracking one down.

Offline LotusJoe

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Re: Radiator Bleed screw
« Reply #4 on: Thursday,July 12, 2018, 04:50:26 PM »
Thanks for the info!  Now it's the challenge of tracking one down.
The radiator shop should have the bleed screw / petcock.
Joe Irwin
3927R TC Special
(The Classic Barn Find)


Offline 4129R

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Re: Radiator Bleed screw
« Reply #5 on: Friday,July 13, 2018, 11:54:04 AM »
Is brazing in a new bleed difficult?

I ask because I have 3 badly rusted long radiator feed pipes, where the vent pipe take-off by the battery has badly rusted.

The combination of hot water and air causes the pipes to rust badly.

I have Araldited 90' brass gas pipe 6mm compression fittings to the big tube ( using a suitable sized 6mm drill to keep the nut in place while the Araldite dries solid).   

Online jbcollier

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Re: Radiator Bleed screw
« Reply #6 on: Friday,July 13, 2018, 03:32:21 PM »
You wouldn't braze, you would solder.  It's not hard.  Meticulous prep is the important part.  Lots of tutorials on the web.