Could be it's a long neck cap on a short neck radiator..
but the last time I saw that done, the motor blew 2 radiator hoses and a welch plug out before the owner woke up.

Spray some WD40 up under the cap, that may free the jammed bayonet fitting enough to let you undo it.

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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.

Give it a couple of gentle taps with a hammer. Not a job for the BFH, though.

I see a Wrong Radiator cap with the wrong neck so not relasing water properly and keeping all presure in except the steam and with the steam rust the cap and neck. I'd give it some gental taps with the hammer also, ensure motor not run for some time before

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Stop Licking the Dog...I Don't Care Who Started It

i managed to get the cap off the radiator before xmas and put some water in the radiator because there was none visible in the top tank at all. (i thought that must have been my problem that there was not enough water or coolant in there)

Anyway i drove it to Willunga and up willunga hill on christmas day and it was fine ran perfect except for what i suspect is a leak from the heater which scolded my foot about 6 times on the whole trip of there and back with boiling hot drops of water.

When i got back home and reversed it down my driveway then i noticed steam coming out the vent in my dash on the radiator side and lifted the bonnet and the radiator was doing the same thing, it was just coming through the dash now because of the angle that it sits on my driveway.

When i checked the radiator again the next day there was no fluid of water in the top tank

Ive checked all the hoses under the bonnet and cant seem to find any leaks at all, the two pipes that go into the heater seem tight, so i can only assume that the water is leaking in the heater or something, even though there was only a few drops of it that would spill in my foot


Anyone got any ideas as to what could be going wrong??

I would bypass that heater for a start.
Check it's not coming from the water pump, or bypass hose (above the bottom rad hose).
I'd fill the radiator, take around the block, then run it up on stands and turn off. You should see any leaks then.
If rad is full it's normal for a bit to come out the overflow as it heats up- the water expands and has to go somewhere.

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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.

what engine does your mini have??

if your car has a standard 3 core radiator it isnt really sufficiant for a 1275 engine. if thats what ur running.

i have an 1100s radiator on my 1275 and it never gets hotter then 96 degrees.

regards matt

Any Oz 3 core from 1965 on will cool it OK, but it MUST be clean. Deluxe/K/ Cooper S/Clubby etc. All have 16 fins/inch, which is 2x what the late Rover UK 3 cores have.
I run a Deluxe one on my 1360, over 125HP at crank and never gets hot.

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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.

ditto..... normal aussie 3 core is perfectly fine - my 1330 rarely gets over 1/2 on the gauge, which I measured at about 80

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did I tell you that I won a trophy?

If it is boiling of that quickly, then you have a problem with your cooling system. As it is a new car i would be going through the steps I told you earlier. If this doesn't fix it, I would have the radiator professionally cleaned.

Does the car run fine? Full power? Is there any sign of water in the oil? (Mayo like stuff under the cap)

Ryan

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Ryan Filippi
Minis In The Gong
[email protected]
www.minisinthegong.com.au

yeh that makes sense. the 3 core ones im thinking of are the after market ones which are 9 fins per inch.

which i used to use on my 1100 and it overheated on 39 degree days.

If you are getting a new radiator get a UK 2 core.

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1964 Morris 850, 1330 Supercharged - 81.8hp atws.
1975 Leyland Mini S 1100S powered - Nice and reliable.
1977 Leyland Mini LS - Project LS-T