Overflowing overflow bottle

[Kevin.payne.15]

I hoped that I had left behind my water problems since my last submission (Vesuvius has erupted) and the gt6 had been running nicely

 

For the first few runs I had checked coolant levels and didn't notice much change

 

However I hadn't filled with antifreeze so tonight I thought I would drain and replace ......only to find that the overflow bottle was absolutely filled up and the rad down on water

 

The only thing I can think of is that the rubber hose betweeen the filler neck and bottle has a leak hence water can drain out but doesn't get sucked up when the rad cools seems logical to me but it doesn't appear to have a leak

 

Has anyone else suffered from this ailment?

 

Thanks in advance

 

Kevin

[Clive]

It could be the rad cap.

Has it got a rubber seal where it fits against the very top of the rad  filler neck (as well as the lower/inner part where it normally seals during use)

If not, it won't suck back

[Gully]

Also check that the lower seal on the rad cap is engaging firmly in the neck of the radiator - if it isn't, then the water will expand out of the system and not return. I bought 3 caps before I found one with a sufficiently deep insert to seal properly. It was a Fahler 13lb one.

 

Gully

[Kevin.payne.15]

Thanks. Where did you find a Fahler cap please?

 

Thanks

 

Kevin

[DerekS]

Hello Kevin, there's an outfit on ebay I've dealt with do Fahler caps including nice ones in polished stainless steel at very reasonable prices. If you have any problems finding them, give us a shout and I'll have a look through my papers for the supplier. No problems with Fahler or the supplier. Cheers.

[Gully]

Thanks. Where did you find a Fahler cap please?

Thanks

Kevin

There are a number of sellers, including www.carbuildersolutions.com which is where mine came from. Their product reference is radcap13ss.

 

Gully

[Dave pb]

Hi Kevin.

 

Did your heating problems get fixed (Vesuvius or this one?).  I had similar problems and the same symptoms a couple of years ago,  and tried everything simple  first - hoses, rad, water pump, thermostat, cleaning it all out etc. Replaced everything.  It still turned out to be a cracked head gasket, which was the last thing I wanted. Confirmed by a  gas-test on the radiator which showed combustion gases. In the end replacing the gasket was much easier than I had anticipated. I used some blue sealant on the new gasket. 

 

Been alright since, although of course there are still all sorts of other problems to fix.  But on the plus side I now have a very efficient cooling system!

 

Dave

====

 

[Colin Lindsay]

I like the Fah-ler safety caps, which have a lever you can use to gently reduce pressure on a hot system, without scalding yourself by removing the entire cap. Available on-line.

 

[rogerguzzi]

Hello All

               They are on offer here! just bought one

http://www.ebay.co.uk/itm/Fahler-Polished-Stainless-Steel-Radiator-Rad-Cap-With-Release-Valve-13lbs-/261872516155?epid=852002147&hash=item3cf8d17c3b:g:dQUAAOSwv0tVQ0-7

 

Roger

 

[AidanT]

Hi

Whilst on the rad cap discussion what's the right pressure and what's it defined by?  My car is a mk1 gt6 but the engine is a mk2 2000

Aidan

[Colin Lindsay]

Go by the engine and not the car, so if it's a MK1 and original then use the MK1 cap, but if it's a MK2 2000 engine then use the cap as specified for that car / engine. Probably 13lbs as opposed to 7?

[AidanT]

Ok  thanks Colin

Aidan 

[Paul H]

Re radiator caps - are they all the same depth when screwed on - I purchased a spare but it doesnt  fit as the internal depth is shorter due to a wider diameter internal base plate - hope this makes sense - I can bend the sealing lips but with twisting it jumps off the radiator lip 

Lastly looking at the Fahr - they look good though dont understand why you would need to release the pressure 

Paul 

[Gully]

7 hours ago, Paul H said:

Re radiator caps - are they all the same depth when screwed on - I purchased a spare but it doesnt  fit as the internal depth is shorter due to a wider diameter internal base plate - hope this makes sense - I can bend the sealing lips but with twisting it jumps off the radiator lip 

Lastly looking at the Fahr - they look good though dont understand why you would need to release the pressure 

Paul 

There are different depths around. I found after replacing my radiator that the cap from the Club shop wasn't quite deep enough. I bought another off eBay, only to find the same problem, but then bought a Fahler one - the standard version without the pressure release lever - and that fits a treat. They seem to vary around the 21-25mm inset depth.

Gully

[Pete Lewis]

The pressure just raises the  boiling point , theres no point in adding extra  the pressure has to take into account the design

Contraints of the radiator and hose contruction  and overflow concept thermostat settings etc , ,  nothing to do with the base  engine origin.