Hi

When I turn the motor off coolant leaks from the overflow tank coming out from the end of the hose but hose seems ok no cracks and tight

maybe wrong type of caps

heres some photos





if they are correct which cap is for the overflow tank and radiator?

Neither is correct for the radiator if you have a Moke or Morris 1100 type pressurised overflow tank- they have a flat cap on the rad and a pressure cap on the overflow tank.

But... if you had a plastic coolant recovery bottle (like many modern cars do now) the cap on the left would be the right sort for the radiator, as it has a rubber outer seal to hold vacuum. But the one on the bottle would be just a vented cap, no pressure spring.

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DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.

My overflow tank is steel not plastic
it looks like this but mounted at the front



but my radiator neck doesnt have the tube sticking out like this pic


the tube is sitting inside not sticking out.

Where can I get a pressurised cap for the overflow tank and radiator cap? anyone knows the part number?

thanks

omg that is nasty!

what do you mean?
the previous photos are not mine I just posted photos I found in this forum.

here's a pic of my radiator neck its a bit dirty, I will flush the cooling system ASAP
note the tube is not sticking out like the previous photo for flat cap



So do I still need the flat cap? and does anyone know where I can get a new one?

Cheers[/img]

If you are using an expansion tank you need the flat cap. You can get them from any place that sells mini parts.

If you are using an overflow bottle you need to use a recovery cap. This is the one on the left in your first photo.

Regarding the photo of the Morris 1100 radiator, the pipe sticks into the radiator neck so that idiots don't fit the wrong cap.

So if you have a tank like the one in the photo use a flat cap on the radiator and a normal radiator cap on the tank.

Morris 1100
I'm confused
My radiator doesnt have the tube sticking out as I stated on my previous post
whats the difference between expansion tank and overflow tank? I got the same as the 3rd pic but mounted at the front

You don't need the tube to stick in to the radiator.

An expansion tank had a radiator cap on it.
An overflow tank is just a plastic bottle to stop coolant spilling on the road.

When the motor warms up the coolant expands and is forced out of the radiator. With and overflow bottle the excess coolant sits in the bottle and when the motor cools down the coolant is sucked back into the radiator.

OK so I have a an expansion black steel tank and I've got the right cap for it (the on with two rubber seal)
now I need a flat cap for my radiator right?

thanks now its very clear

Yes, U got it..

_________________
DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.

i got my blanking cap (flat cap that fits on rad) from mini padstow for about $10. you need abit of grease to get it on real tight.
solved my coolant-surging-everywhere problem.

_________________
Inconspicuously Conspicuous
Appreciation without Depreciation
forever chasing clearer skies...

sorry to bring this old thread back
I bought the proper flat radiator cap

but i drove the mini today, the longest time since I got it
and when I got back home coolant was coming out from the hose of the expansion tank
it wasnt overheating
maybe too much coolant?
should the expansion tank be full or empty when motor is cold

Water expands when heated, so it will overflow the expansion tank if you fill it.
Leave it an inch or more below the neck...

_________________
DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.

Cheers Doc will check and test it again.