Swirl Pot problem?
Discussion
Just been out for the first time in 6 weeks. When I got back I took a peek under the bonnet to check the brake fluid level as I'd just changed the rear cylinders and shoes.
The first thing I noticed was coolant leaking from the under the cap on the swirl pot. I have a pressure cap on the pot and a blanking one on the expansion tank.
Temperature was up to normal, fan kicked in as usual.
As I understand it the pressure cap should rise and coolant flow into the expansion tank, returning when cool.
I check the pot-to-tank hose, it was not blocked. I blew into the expansion tank and water returned to the pot.
I can't think why coolant was leaking out of the underside of the pressure cap.
Any ideas?
Thanks,
Steve
The first thing I noticed was coolant leaking from the under the cap on the swirl pot. I have a pressure cap on the pot and a blanking one on the expansion tank.
Temperature was up to normal, fan kicked in as usual.
As I understand it the pressure cap should rise and coolant flow into the expansion tank, returning when cool.
I check the pot-to-tank hose, it was not blocked. I blew into the expansion tank and water returned to the pot.
I can't think why coolant was leaking out of the underside of the pressure cap.
Any ideas?
Thanks,
Steve
There's no rubber seal on the cap. Never was.
I assumed that the seal was made by the rubber on the bottom of the pressure spring and that when it lifted water should just flow into the expansion tank.
I'll nick the seal frokm the expansion cap and try that.
The top of the pot is flat and undamaged.
The cap is the QH one listed on the parts list so I assumed it had the correct type of return valve.
I assumed that the seal was made by the rubber on the bottom of the pressure spring and that when it lifted water should just flow into the expansion tank.
I'll nick the seal frokm the expansion cap and try that.
The top of the pot is flat and undamaged.
The cap is the QH one listed on the parts list so I assumed it had the correct type of return valve.
Edited by SteveOS3 on Saturday 1st September 19:58
Without wishing to start a multitude of posts on this, I have noticed that the water level in my swirl pot keeps needing a top up, despite there being coolant in the expansion tank.
There are no signs of any leaks, but I have wondered if I had the wrong type of cap on that does not allow coolant to return to the Swirlpot??
When I bought the car, it was quite obvious the swirlpot cap was no good by the amount of coolant seeping down the pot, so I bought a 15psi (I think) pressure cap for a Granada.
Sorted the leakage issue, but still have to top up as said previously.
Does anyone know where I can get the 'correct' pressure cap from?
Thanks
There are no signs of any leaks, but I have wondered if I had the wrong type of cap on that does not allow coolant to return to the Swirlpot??
When I bought the car, it was quite obvious the swirlpot cap was no good by the amount of coolant seeping down the pot, so I bought a 15psi (I think) pressure cap for a Granada.
Sorted the leakage issue, but still have to top up as said previously.
Does anyone know where I can get the 'correct' pressure cap from?
Thanks
when ul to temp / pressure the spring opens and if its like mine was the water escapes from top of cap.. I tried different caps rubber seals etc but mine was never 100% even with blanking cap in I believe this was down to poor condition if swirlpot neck.. ACT item wasn't much better so ended up sealing the top of the swirlpot and leaving pressure cap on expansion tank. This is not ideal for filling the system though.. Its not far off and a different expansion tank and pipe mods would fix this. Ie route water pump bypass to far side of rad and run water top up from header to now spare port on swirlpot.
that said what I have now works well once the system is full.
Good luck looking at the engine bays at thornby this is a common problem.
cheers D S3
that said what I have now works well once the system is full.
Good luck looking at the engine bays at thornby this is a common problem.
cheers D S3
One question is "what has changed in the last 6 weeks?"
I had a Related issue when I got a new st st swirl pot which was due to failure of the brazing of the neck to the main body - could look like the cap was at fault even though it wasn't.
Is yours st st - could be a similar problem. If you'd is mild steel then has corrosion changed something?
Just a thought to throw in. ...
I had a Related issue when I got a new st st swirl pot which was due to failure of the brazing of the neck to the main body - could look like the cap was at fault even though it wasn't.
Is yours st st - could be a similar problem. If you'd is mild steel then has corrosion changed something?
Just a thought to throw in. ...
Can of worms again - I've said it before and will say again both ways should work UNLESS you have the expansion tank with the blanked hole (plastic weld toward middle of front of tank) so it won't take pressure (in this case put pressure cap on swirl pot only) or you have a single way pressure cap without bleed back - in this case put pressure cap on expansion tank only - clearly a combination of blanked hole and no bleed back cap won't work at all
Running and hiding
Running and hiding
Swapped the caps over, blanking now on swirl pot and pressure on expansion and got the same problem. To me this proved that the issue is with the seal on the swirl pot.
I twisted the blanking cap around a bit and the leak stopped, expansion tank began to fill, pressure cap opened after a while and coolant drained to the floor.
Not sure what can be done about the swirl pot rim but will try the newly ordered pressure cap and fiddle with it until a seal is made.
Steve
I twisted the blanking cap around a bit and the leak stopped, expansion tank began to fill, pressure cap opened after a while and coolant drained to the floor.
Not sure what can be done about the swirl pot rim but will try the newly ordered pressure cap and fiddle with it until a seal is made.
Steve
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