Talk Morgan Forums Morgan Sports Cars Maintenance & Servicing Replacement of top hose on Plus 8

Just done the replacement as the old top hose was delaminating (thank you Keith at BHM for spotting this).
First i noted that the header tank was completely empty.
Having disconnected the top hose and captured the spillage, replaced the hose and after straining the spillage and returned it to the header tank i noted that the level in the header tank was now correct?
I ran the engine up to fan cut in and out temp then left to cool for a few hours. Header tank still shows level ok.
So, question, how has the system filled up when i could only have replaced 90% of the fluid spilled as a little went onto the garage floor. I then had a look at the levels. The level indicator in the header tank is lower than the top of the radiator. So i am wondering just how it all works. Is there some syphonic action taking place via the small bore tube that connects the header tank to the radiator? HELP me to understand this as i am certain that the system can not be full.

Air locks can be a pain on a +8. Mine sometimes takes weeks to resolve its self, keep checking and topping.

Ahhhhhhh!

The tank isn't a header tank
It's an expansion tank....
It only needs enough water to cover the indicator , no more
The radiator is filled through the filler neck ( it may take a couple of goes to work out the airlocks, as mentioned )
As the coolant expands and contracts dependent on temperature the expansion tank will either fill slightly or thermosyphon coolant back into the system

Simon @ Sifab.co.uk

Ok so the "filler neck" is that on the top hose connection?
I see there is a fitting but is that a removable filler point? It doesn't look like it should be removed?

What year is your +8?

Simon @ Sifab.co.uk

1993

Is there no cap on the rad Ken?

1993 +8 has top hose going from thermostat housing to hose stub on the top left ( looking from drivers seat ) of the radiator
On the right side of the radiator is a filler neck fitted with a blanking radiator cap. This filler neck has an 8mm hose running to the expansion tank

Fill the radiator up fully using the filler neck. Stick a splash in the expansion tank to reach the level indicator. Run the car up to temperature , re-tighten hose clips while hot, allow to cool and recheck coolant levels in both the radiator and expansion tank
Adjust if necessary

Simon @ Sifab.co.uk

Thanks guys, guess what, i thought it would be simpler than this, but they all do that sir, don;t they!
Will try it again tomorrow and report back.