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SBC 350 under cooling

Pantera

Member
My SBC350 DD with 72 inch Whirlwind prop does not come up to temperature as it should, runs cold not hot.
This summer engine ran 130 - 160 degrees, idles between 1000 - 2800 rpm, Now air temps under 60/70 degrees make me concerned that low operating temp will not get rid of moisture and sludge up motor oil.
Looking for ideas to obtain a operating temp 180-190 degrees.
Could the fan be drawing too much air across motor and radiator IE real efficient cooling system is good thing but with consequences.
Would covering the radiator and monitoring coolant temp or changing water pump pully to obtain slower water pump speed IE lower coolant flow help. Currently running headers no mufflers would adding mufflers benefit operating temperature?
Thanks for any ideas/comments.
 

Slidin Gator

Well-known member
It sounds to me like the thermostat has been defeated or removed. A new 180 degree thermostat should put you in the range you are looking for.

Keep in mind that the cooling system should be setup to maintain temperature under full load (which sounds like you have covered). The thermostat keeps the system from over cooling at lower loads.
 

Pantera

Member
Appreciate that Slidin Gator, will get new stat and change it, that's easy to change then see what's up with the old one.
 

Pantera

Member
Finally getting around to working on this under cooling issue. Turns out original owner ran without the thermostat. Recon that's why 130 - 160 was as hot as it got this summer. Not complaining about not over heating! More concerned about optimizing fuel burn. Spark plugs looked great tho! Running new 180 degree stat and seems motor is running up to 180 -185 now. There is a couple degree diff between temperature sender/guage and heat gun checks but I think I'll live with 5 degree diff for now. Slidin Gator and kwanjangnihm thanks for your inputs!
 

SWAMPHUNTER45

Well-known member
Just keep in mind that now that you will be running in hot weather up around 185f+ as opposed to 140F your timing and fuel octane becomes more critical.

Octane helps to prevent detonation which is the premature ignition of fuel.
 
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