i have a 1987 classic 3.5 V8 EFI Manual. I bought it in november and have covered about 6000 miles in it. I recently overheated and found that the radiator was clogged up with mud that i stupidly had not cleaned off. The engine always ran hot anyway before this up at the far end of the white line just before the going into the red. I have replaced a couple of hoses that were old and fitted an 82 degree thermostat, and new viscous drive to the fan but i am still running hot but not overheating. I loose no oil or water and it is not mixing, i have no bubbles in the expansion tank but the top hose does get quite firm. She runs lovely apart from this and i am not convinced the head gasket has gone. Anyone got any ideas?

Hi ranover, I would personally at least remove your radiator and have a flow check done on it by a local radiator re-conditioner.

If this is not possible you could remove the front grill, run the engine up to temp, and feel the front of the radiator for cool or cold areas in the radiator normally around the edges away from the centre.

If the radiator is unable to dissipate the heat quickly enough the engine temp will rise until the heat input/output ratio balances, a partly blocked core is normal in older radiators.

I'd personally fit a new radiator at least that way there is no doubt that it doing its job properly.

Theres a couple of traders on ebay that have fair prices, if your radiators not listed just ask them.

hth

zzr

I'll second fitting a new rad - some recon rads don't last very long at all
V8's HATE running hot - a new rad to try and cure it will always be your cheapest option

You might try the transmitter. Redplace it wiv a new one just to be sure you are getting the correct reading. Dont forget its a gauge to indicate temp. It is not and exact measurement. If the new transmitter reads the same, then trust its reading.

Hi Ranover, i had some trouble like this when i got my RRC, although mines is the 3.9 efi auto. After trouble with losing water, and overheating, i replaced the expansion tank, that solved the loss of water, The overheating occured at one point and was very severe, i replaced the thermo with a new one. Still over heated on me, Then a mate of mine checked the timing.............it was out by a good bit, So twisting the Dizzy clockwise made it run much better and solved my overheating problem, although i do think it was a mixture of all these little things. If you can get your timing checked it could help.
If you can't afford a new rad at the mo, then i would at least try and flush it out and put alot of antifreeze/antiboil in it to help it cool better.

Be careful with the concentration of anti freeze 50% max. Anti freeze above this concentration can reduce the heat transfer from engine to coolant and out to the rad.