Quote:
Originally Posted by dingdong1960
Hi ..diesel ...runs normal temp around town ..soon as i go up hill ..car overheats !.and starts rattling ! ..which stops as car cools down ...any ideas??
Fan works ok ...no bubbles in header tank ..tho bottom hose dosnt seem to get hot ..unlike top hose ...
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It could be a faulty thermostat or other part of the cooling system preventing the correct coolant flow when hot, especially as the bottom hose is notably cooler
Does the noise sound more like a crackling sound than a rattle? you can get this noise when due to insufficient cooling, or sluggish coolant flow, when the coolant reaches the hottest parts of the head, which will be hotter than normal, it forms ' steam ' bubbles, this steam bubble quickly reverts back to water due to the bubble moving through the cooler coolant and the coolant being under pressure.
There will be no bubbles seen in the coolant when this happens.
When it's doing it you should also be able to feel the pulses in the top hose with engine off if you're quick.