Series 3 heater control valve leak

JerryP

Member

Posts

15

Location

Gloucestershire

• Jun 25, 2019

• #1

Morning

My S3 (88 2.25 petrol) overheated very rapidly recently, normally runs fine in centre of temp gauge when warmed up. Coolant sprayed all round engine bay (see gif). Assume diaphragm in heater control valve has failed, or am I barking up the wrong tree? Grateful for any ideas, thanks.

 

R

rob1miles

Well-Known Member

Posts

3,565

Location

Slough and Bath

• Jun 25, 2019

• #2

Yes, and I don't think there a lot you con do other then get a new one.

 

W

Webley1991

Well-Known Member

Posts

2,579

Location

London

• Jun 27, 2019

• #3

I removed mine completely and replaced it with a simple brass elbow connector and hose tail. That means that water is flowing into the heater matrix permanently.

Being a Series, I don't even notice that heater is "on" when the fan is switched off.

I decided that this was a safer option than replacing with a cheap modern production valve.

 

R

rob1miles

Well-Known Member

Posts

3,565

Location

Slough and Bath

• Jun 27, 2019

• #4

My S2A has the manual tap type but when it leaked I replaced with a much older version that was repairable as the modern ones are sealed and when they leak they are junk.

 

K

Kipperthedog

New Member

Posts

8

Location

Oxford

• Mar 27, 2021

• #5

I hope it's ok to resurrect an old thread.....

I have a leaking valve on a 2.25 diesel and like the idea above of a simple elbow. I presume it is a bsp thread that is required but can anyone tell me what size thread and hise barb are needed please? I know I can measure it but would like to have one ready to fit when I take the leaky valve off ideally!

 

R

rob1miles

Well-Known Member

Posts

3,565

Location

Slough and Bath

• Mar 27, 2021

• #6

It depends. I seem to recall the valve is screwed into a fitting that is screwed into the head. I think there are different threads each end. I'm pretty sure one is BSP but the other one is not.

 

Blackburn

Well-Known Member

Posts

3,105

Location

Tyneside

• Mar 28, 2021

• #7

Series 2 parts book lists the rear connection for heater hose as 3/8BSF not sure if that carried over to later engines.
Front connection is 3/8bsp

 

Attachments

• 
  Capture.JPG

  19.3 KB · Views: 149
• 
  Capture 2.JPG

  16.7 KB · Views: 147