Topic

Hello all

not been on here for a long time - apologies but have been spending every spare minute trying to sort out the cooling on the TF. - 2 months so far. Engine runs at normal temp while the heater control is set to max but overheats as seen as the heater is turned down.
So far have replaced the thermostat. Fitted stainless engine pipes, Mike Satur aluminium radiator and Brown & Gammons coolant level alarm (due to coolant loss after letting a local garage have a look at it) . Still got the same problem, so today I drained the system yet again and checked the hoses for blockages as suggested by the tech line at the MGOC.
Reassembled everything, filled and bled the system and now things seem to be ok (fingers etc crossed). But, and it's a big but, when i was decanting the used coolant into containers for disposal I found a lovely shiny ball bearing sitting at the bottom of the bowl used to catch the draining coolant.

I take it this is not a good sign

Set to drain the system again tomorrow - ball bearings being gregarious creatures.

Do not like the sound of that at all. David is more of an expert on cooling systems on Fs and TFs ~ there is a jiggle valve in the system somewhere, which could be where the ball bearing has come from??

Have you got the PRT thermostat system?

Are you sure that all of the air has been bled out of the system from all bleed points including the heater.??

Did you back flush the system with water before refilling with new coolant.

David has fitted an automatic air vent to his radiator bleed point which works well.

Did you also replace the pressure cap on the header tank (Bottle) and not use the old one?

Please keep us informed with progress.

Take your inlet manifold off and look at the waterways on either side.




If this is missing it will cause everything you have mentioned.

hi
this ball bearing could be from one of the 2 juggle valves that bllet the system (or supposed to) one is in the inlet manifold the other is in the top return pipe to the left of the head looking from the back of the car

my old blue f use to over heat on tick over if the haeater was off
i never solved it , i replaced the cap 3 times 4 thermostats and did the mod on 2 thermostats ect
i sold the car to some one in scotland and hes had a play and is still not running correctly

good luck on getting it sorted

I have flushed the system must be at least 3 times now, and have replaced the cap 4 times including the new cap and bottle that came with the alarm kit.

The inlet manifold is the alloy 2 piece one - doesn't look like the one in the photo - although these have been off to access the thermostat ( not the PRT type unfortunately) - had to go in from the top as car was parked on mud after being trailered back from the garage. So possible it's from there if there is a jiggle valve in the manifold as the inline jiggle valve still jiggles if that's the right word.

The only source of ball bearings in the coolant is the jiggle valves. I would suggest that one of them has collapsed releasing the ball bearing. This has, no doubt, lodged somewhere inconvenient blocking flow to part of the engine. Hence the excess heat.
Now the ball is out normal cooling is resumed.

That's what I would think has happened.
There shouldn't be any problem caused by the lack of jiggle valve, as normally they cause difficulties by jamming shut, trapping air.

Hopefully, as you say, all is well now.

Cooling system taken apart again, flushed and refilled no more new arrivals! . Engine temp running exactly where it should be and the radiator is now warming up so all looks well

Only problem now is slight weeping from the bleed valve on the new radiator but will get that sorted next weekend when its not raining - hopefully.

Test drive later today if the rain eases off - not precious, but if I break down its always in the rain so not going to temp fate.

Hoping now that the overheating hasn't compromised the head gasket - no sign so far, so fingers crossed.

By the way this is what caused the coolant leak in the first place - so take care with the O ring if replacing this type of thermostat



not my doing that's how it came back from the garage.

when changing the thermostat ALWAYS replace the o rings its faulce ecconamy not to

they are only £0.99 for both

MGF MARK wrote: wrote:

when changing the thermostat ALWAYS replace the o rings its faulce ecconamy not to

they are only £0.99 for both

couldn't agree more.

Test drive done -all working as it should.