ok ,have looked back on your posts,
mine is a perkins diesel but here is a summary of my overheating problems
could leave the engine at idle for hours without overheating - driving soon caused overheating - especially when at 40mph and over.
heres what i did...
changed thermostat - no effect
changed waterpump - helped a little
changed from a mechanical fan to a kenlowe - helped a little
recored the rad - helped a fair bit
overhauled the fuel pump - helped a bit
set the fuel pump timing - helped a lot
wrapped the exhaust manifold - reduced engine bay temp a lot
changed the rad cap (the wrong one was fitted)
changed the head gasket twice (both times saw a small amount of evidence suggesting partial leak)
slick 50'd the oil
in desperation - put a bottle of engine block weld (not sure of the actual name) says it seals leaking head gaskets, cracked blocks etc
seems to have made a dramatic improvement - can drive at 40 without the overheating (well ok it did first time but that was because I filled the rad to the top and it had nowhere to expand)
another thing I looked at was exhaust back pressuring (this was suggested by perkins)
I took the exhaust silencer off and found the engine so much more responsive - as a result I have ordered a straight through back box which should again reduce exhaust temps
If I had to pick one item that made the biggest improvement - it was the bottle of jollop that claims to seal all leaks
The Dog is home....
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