Hi
Does anyone know how to keep the heat down on a rebuilt A12. I know running these motors on unleaded these days makes the motor run a little hotter, but on hot days it really starts to run too hot?

The radiator is tiny as standard, but is in really great nick. No overflow/ surge tank at all - should I put one of these on, or is there something else I can do to run it a little cooler?

Normal around town running about is ok, but on the freeway at about 90km it's not the same case.

Suggestions please

you need to make sure your running the stone tray between the frount of the car and the cross member

seal up as many holes as you can in the radiator suport panel as you can neatly and make sure the radiator is sitting flush this makes as much of the available air flow through the radiator as possible

I'm not sure what you mean by 'stone tray' - Do you mean the front apron. Excuse they lack of knowledge, but the crossmember - what does that look like exactly?
I'll have a look

Thanks

the first thing I would do is put in a new thermostat,flush the cooling system and fill with a good quality coolant.
ade

Do you have a picture of your engine bay? Would help a little bit. Would like to see how ur running everything
Cheers

what if you cant run the stone tray due to mods on the fron radiator support panel underneath..? would a flat piece of metal do?

It's not uncommon for rubbish that is in the cylinder block to be dislodged when an engine is rebuilt, & this of course finds its way into the radiator, partially blocking it & causing heating problems.

I suggest that you drain the radiator enough so that you can clearly see the top of the core. You will be able to see only a small number of tubes, but look to see if they are blocked with rusty looking particles. If they are even partly blocked, it may pay to have the radiator reverse flushed.

Hopefully this will fix the problem, but if not, then a full tanks-off radiator service may be called for.

Stone tray or frount apron can be made from flat sheet if you want but put some cross folds and peen over the edges a bit as they are exposed to quite a loot of stress

oh and bolt them up good they make a mees if they fall off

good luck