Have have a 450 sl that is constantly running very high engine tempertures in the Texas heat (red mark after highway speeds).
I have changed every thing in the cooling system with no improvement.
I read here that with aftermarket parts wrong fan to radiator clearance could result.
I changed the water pump and fan cluch with aftermarket parts.
Does anyone know what the right clearance should be?

Don't forget to check your engine timing....wrong timing can make the engine run very hot and/or overheat.

Thanks for the advice.

I have already checked the timing and it is right on at TDC.

One other thing....make sure that your V-belts are not worn to the point that they are slipping at higher speeds. Not likely, but still possible.

do you have a shroud around the fan? that will help the air flow by letting the fan make it's draw thru the radiator fins only. this is very important.

if the radiator has plugged tubes that would also create a problem. see if there is a rad shop that still knows how to do a tank and rod job. you didn't say and i am assuming you have metal tanks.

if you changed the fan with one of those flexible ones be sure to leave enough room for the flex. was the pump new or rebuilt. the rebuilt units could be suspect for lower flow due to the old impeller being reused.

are your auxillary fans coming on?

hope you solve it.
craig

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Thanks Much!
Craig

1972 350sl Red/Blk 117k
1988 420sel charcoal/Blk 140k
1987 420sel gold/tan 128k
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