The Stovebolt Site Forums The Parking Lot '60-'66 Trucks Cooling question for you gents

I have 65 chev shortbox,I recently installed 383 stroker with aluminum rad that fits perfect where original rad was,2500 cfm electric fan,muncie m-20 4 spd,my question is will a shroud help in cooling engine,it runs 170 down road but in city driving gets up to 200,what bout rad cap,,not sure what the rad came with but will installing a less pressure cap help in cooling?.Im assuming its a 15 lb cap.it doesnt say,Ive got a 50/50 mix,180 thermostat,any ideas,also timing is good,any takers? thanks

Yes, a shroud will help in cooling the engine. If they didn't then they wouldn't be used on factory OEM vehicles.

200 F. not that hot at all, you are running modern parts that are designed to run 195 to 228 F. all day long. It's the 170 on the road that I don't like, too cold.

yes you need a shroud, you'll get proper cooling at low speeds, and you need the 14-15# cap to allow it to run the necessary high temp without boiling - but I'd question the stat or your gauge, a 180 stat shouldn't allow it to be 170 continuously .... with a shroud you could be using a 195 stat and it should stay right about 195-200, fast or slow speed

Bill

thanks guys will check stat for sure,i might have bad one,as always thanks for input!!

With an electric fan attached to the radiator a shroud should be unnessary. How much surface area does you fan cover. If it is a small fan on a large radiator you are only blowing air across some of the cooling fins. You may need to build a custom shroud so your fan is pushing or pulling air across all of the core. The factory V8 shroud wont work with the electric fan.

its a 16 inch fan on a original fitting aluminum radiator,going to try thermostat first,its funny why a 180 will run at 170 on highway,new autometer guages,hope they are true,also ive noticed it fluctuates going down highway,thermostat I think,

Is the fan running the right direction, get a good stat (Stant) mine has a 195 with a 13-14 cap and sits right on 195-200 winter or summer. Any bubbles in rad or losing any water???

I would check the therm also. About half the new ones we get arn't any good, but I think 180 is best. What temp. does the fan come on at. It may be set at 200. If so that is about right. If the system is all in good shape a 15 lb. cap should work good.

A little trick to check a thermostat is to place it in a pan of water on the stove and use a candy thermometer to watch the temp and watch if and when it opens. Just dont let the wife ketch ya!

Where is the temp sending unit for the gauge installed?

yup, going to check the stat,,dont have candy therm,,probably a good thing,get my #ss kicked,fan is running right direction,not loosing antifreeze,fan kicks in at bout 195,,i just think thats to hot,,maybe not,its gone up to 200 and I got scared,,this is all happening on 50 degree day,,when it gets 70 or 80 outside then not sure,,it has aluminum heads also,but from what ive been told 200 is not abnormal,,its a new engine so maybe it will simmer down in a while,,thanks for all the input guys,,

temp sending unit in head,yes will make it seem hotter,,,right?

won't make it seem hotter, the water temp is what's being measured, and that'll be much the same anywhere in the top of the engine .... one thing you haven't mentioned is whether you've used a good thermometer [as in a hand held laser infrared one] to check the real temp, including at top and bottom of the rad and on the thermostat housing

also as stated above, 200 is not hot for a modern small block, what's much more worrisome is running cold for long periods, which is what the 170 is, check the recommended stat rating for the engine and year, I wouldn't be surprised if it was a 195 .... the way a stat works is to set the minimum temp the engine will run at, the stat should open within +/- a couple degrees of the rating, so if your 180 closed at about 178-180, it wouldn't be possible for a continuous 170 reading to be correct

from your descriptions I think your cooling system is overkill for the highway and not moving enough air thru the rad at stop and go .... and you need a higher stat, or at least a different [not defective] one

Bill

ok,,thanks for info,,gonna buy GM stat,,not sure what engine builder put in there,,my buddy also said you get bad stats,,thanks,

ok,,thanks for info,,gonna buy a genuine GM stat,,not sure what engine builder put in there,,my buddy also said you get bad stats,,maybe GM buys a better product than others,thanks