Topic

I have a 2004 MG TF with the original coolant alarm fitted when I recently check the coolant level I found the needle magnet lying in the bottom of the expansion tank I've read about these magnets becoming detached and wondered if anyone has any experience of reattaching the magnet to the float

Hmm , going have to check mine now aren't I ? You just know if I don't it be me at the side of the road with steam coming from every orifice !
John 👍

sworkscooper wrote:

with steam coming from every orifice !
John 👍

You should probably see a doctor about that!

I had the same on my latest TF, Unfortunately no sign of the magnet though! Had to buy a new expansion tank.....nice and crystal clear! May be a better option as it was hard to find one, Only place that had them in stock was Brown and Gammons. Maybe some more have come into the country by now!

Sundance

I have a feeling that the float and magnet are assembled before the two halves of the tank are welded together so reinserted the magnet could be a challenge.

Does any one know where the magnet inserts? Is it in the bottom or side of the float? Any photos of a dismantled expansion tank would be a great help if anyone has a failed tank.

In case anyone is interested the magnet is 2mm in diameter and 20mm long.

Gavin207 wrote:

In case anyone is interested the magnet is 2mm in diameter and 20mm long.

I hope you ment vice versa: 20mm in diameter and 2mm long.

No it's a cylindrical 'bar' magnet

Ok, then this is the page to help you with pictures where that type of magnet should be:
http://www.apttony.co.uk/Servicing/CoolantAlarm.html

Took a picture of the float with my endoscope today - you can see the hole for the magnet in the float. Next is to try reinserting it with my trusty surgical clamp.

When did the coolant alarm become standard?

Mines 05 reg, built in Feb 05 , I think they started fitting them late 54 reg but I could be wrong .