29 replies to this topic

[PACINO]

Hi guys! How is everything going? I've got a little problem. A month ago they completely my car with the rebuilt engine. High compression pistons, camshaft (SW5)...etc.
The engine reaches the optimal working temperature (90°C) very soon. But the heat is overwhelming like these summer days, the needle easily goes to 100/120 degrees as soon as you are stopped.
The car;a 1972 Austin Mini, now 1310cc, double S.u Hs2 carb and standar radiator with 11blades yellow plastic fan.

Wich would be the best option to improve the cooling?
The super two cores radiator (C-ARA4443) like Minispares advise me, or an electro fan in the wing prepared "just"to cool as soon as the temperature goes above 90 degrees?

Kind regards
Luis

[sonscar]

I would check the engine tune before anything else.Steve..

[PACINO]

I would check the engine tune before anything else.Steve..

bad positioned dizzy?

[mab01uk]

Even Rover fitted an additional electric fan under the wheelarch to the later 1275cc & Cooper Minis in the end. Back in the day I nearly always had to put the heater and blower fan on in slow moving traffic queues on a hot day in the UK, especially with a modified engine spec. Since fitting a Rover Cooper electric fan and a manual switch I can keep the temp gauge around normal no problem.

 

This is the Rover Mini SPi electric fan which is pretty easy to fit under the wheel arch of an earlier Mini by just drilling 3 holes in the inner wing and I think i added some small spacers to the support mounting legs as the SPi has a large hole cut out for the fan blades to sit in closer to the radiator.





Minispares:-
"This radiator electric fan was fitted as standard on minis with the large round hole cut out in the inner wing fron 1991 on the last carb models through to the SPI but there was an earler type which is no longer available that was on earlier 1275 cooper carb models." (RSP Cooper)
 http://www.minispare...c/PGG10058.aspx

 

[alpder]

One simple thing... is the fan the correct way round?

[PACINO]

One simple thing... is the fan the correct way round?

Of course, that's the first rule. "ENGINE SIDE" leyend, opposite to radiator. But thank you for your help.

[nicklouse]

Timing correct?

mixture correct?

don’t use an alloy radiator.

dont use too much antifreeze/rust inhibitor mix as it reduces the ability of the liquid to transfer heat.

[cal844]

Timing and curve, mixture, ideally use a copper radiator.

Another thought is to fit an aftermarket secondary (electric) fan. I fitted an ebay special to my minis, with a manual switch on the dash, total cost was around £30 all in (wire, crimp on terminals, and the switch)

[PACINO]

Even Rover fitted an additional electric fan under the wheelarch to the later 1275cc & Cooper Minis ...

Thanks a lot mab01! The electric fan is a possibility, but after the correct timing and when discard a new radiator.

[PACINO]

-Timing? Not sure it's on point, but very close. I've this pending.
-Mixture? Close to the light brown color and I continue adjusting.
-Radiator? Copper (standard).
-Antifreeze? Inorganic Krafft 50% (I want to put Mercedes blue on it, much more expensive.

Edited by PACINO, 30 July 2024 - 09:36 PM.

[StefanMini]

I have a Fletcher alloy radiator, no cooling problems at all and very happy with it on my 1293 stage 3 Mini. I even changed the cooling fan back from the steel 4 blades to the original plastic unit because it was cooling too much.

[nicklouse]

-Timing? Not sure it's on point, but very close. I've this pending.
-Mixture? Close to the light brown color and I continue adjusting.
-Radiator? Copper (standard).
-Antifreeze? Inorganic Krafft 50% (I want to put Mercedes blue on it, much more expensive).

https://i.ibb.co/rd9...descarga-4.webp

Link does not work. Try Imgur 

[alpder]

If I'm reading the charts correctly, 50/50 glycol/water is about 35% more viscous than 30/70 (at typical engine temps). It also has a few percent lower heat-carrying capacity. Upshot is that the more concentrated stuff circulates more slowly and moves heat less effectively. The figures can be had from here: https://www.engineer...ycol-d_146.html

 

I found out years ago that this makes a useful difference to cooling. On a kit-car with a tired old Pinto and an even tired-er old radiator in it - with 50/50 mix it would often overheat. With 30/70 it ran fine.

 

So unless you really need the antifreeze to be 50%, try 30% instead. Might make all the difference.

 

[IronmanG]

Electric fan from wired by wilson,and fit a cowl to duct the air between the rad and inner wing

[PACINO]

If I'm reading the charts correctly, 50/50 glycol/water is about 35% more viscous than 30/70 (at typical engine temps). It also has a few percent lower heat-carrying capacity. Upshot is that the more concentrated stuff circulates more slowly and moves heat less effectively. The figures can be had from here: https://www.engineer...ycol-d_146.html
 
I found out years ago that this makes a useful difference to cooling. On a kit-car with a tired old Pinto and an even tired-er old radiator in it - with 50/50 mix it would often overheat. With 30/70 it ran fine.
 
So unless you really need the antifreeze to be 50%, try 30% instead. Might make all the difference.

Well well well, maybe you're right. I've been looking for my old 5L antifreeze container used before my engine's restauration, and it is 30%.



Maybe there is the issue.