K Series Radiator Without Bleed Valve

[Skipper555]

So it looks like my K Series radiator isn't as standard and doesn't have a bleed screw, but an extra take off. At the moment there's a short length of pipe with an allen bolt in the end, which kind of works but is fiddly to get it properly bled.

I've tried looking for a bleed valve  or tee piece I could put in here, but they all look to be for bigger diameter pipe.

Does anyone have any recommendations for how I could improve the bleeding situation?

Cheers

[Jonathan Kay]

4 minutes ago, Skipper555 said:

I've tried looking for a bleed valve  or tee piece I could put in here, but they all look to be for bigger diameter pipe.

What's the outside diameter of the radiator stub and the inside diameter of the short rubber pipe?

Jonathan

[SM25T]

Use the bolt in the pipe to let air out when the front of the car is raised. By the way, the bobbin looks a bit perished ?

Edited May 4 by SM25T

[Skipper555]

I'll try and take an accurate measurement tomorrow, but I think it's roughly 8mm diameter.

I did unscrew the bolt to do the bleeding, but it felt a bit messy to do that when water was coming out of there.

The perished bobbin is on my todo list 😁

[AndyOH1697456946]

What I found worked for me was to remove the hose with the bolt in and connect a new piece of hose about a foot long (after I had raised the nose up), then I made a funnel out of an old washing up liquid bottle by cutting off the bottom and then connected this to the free end.   I then supported the funnel in the upright position.   This meant that when the engine was running air could still escape via the hose and funnel, however it also  meant that I wasn't drawing more air back at any point in due to the head of water in the funnel.   Just be careful as the coolant in the hose still gets hot.  Then when the engine was cold I could tip the water out of the funnel into a bucket remove this assembly and replace the old hose.  Hope this makes sense and good luck - Andy 

[Skipper555]

That's a great idea, thanks for the recommendation, I'll give that a go

[Wrightpayne]

What about a wheel schrader valve fitted into the extended tube?

[Skipper555]

Interesting idea. Would it be big enough diameter? Also would it cope with the coolant temps OK too?

[OldAndrewE]

41 minutes ago, Skipper555 said:

Also would it cope with the coolant temps OK too?

I would think temperatures would be OK considering what temp wheels and tyres can get up to on a track.  

And as a backup leave the cap on the valve, that should stop any leaks

Edited May 4 by OldAndrewE
Note about cap added

[WobblyWeb]

Similar query from a previous thread with solution for self-bleed plumbing.

Edited May 5 by WobblyWeb
typo

[Skipper555]

Thanks for this. I didn't find that thread before, and the picture with the t piece on the modern coolant tank is really helpful to explain it.

Thinking about this initially I was concerned it would just allow coolant to bypass the rad but I guess as the tank is pressurised to some degree it prevents that from happening.

I've ordered some hose, brass t piece and clips to implement it that way. Thanks again

[Skipper555]

To follow up on this, the T piece mod has worked great for me. Temperatures solid during driving over the weekend, fan kicking in when needed.

Very happy with the recommendation.

(I'll swap the jubilee clips for smaller sizes when I get some)

[Jonathan Kay]

I can see the T piece. Is there a new bleed valve somewhere?

Jonathan

[Skipper555]

I've not fitted a bleed valve as it should automatically bleed air back into the tank from what I understood from this post.

However I've not tested this when filling the system up from empty.

 

[Jonathan Kay]

Thanks

Jonathan