jerpazz

Any help is greatly appreciated. :shock:

I purchased this radiator brand new in box - It's a 16 AN/cross flow Double Pass - 3" (2 row) aluminum Fluidyne.

Engine is a 1968 427 BBC ~550 Hp - in a 2200 lb. 4 speed manual trans car.

I am running the AN fittings direct from the front 2 ports of my intake manifold. I have 2 electric fans (pull thru) and a very air tight shroud as well. My temps are ridiculous - after 5 mins of driving - 220 - 240 deg.

I don't have any restriction (slowing the water flow) - as would be there w/ a thermostat, have tried the fans on both sides (push & pull). Have tried w/ and w/o the elbow bypass hose coming off the top of the water pump to the intake - same prob.

I know the motor is jetted properly
I know the heads are tight (not leaking thru head gaskets anywhere)
I know the timing is right

heres a shot of the radiator:


here's a shot of my application:


Any suggestions would be great...

oh.. and am running the temp sender off the passenger side center of the head.

DirkaDirka

Have you tried to switch the 2 hoses coming from the radiator?? They might be on backwards and you could be pulling the hot water from the top and not the bottom. JMO

jerpazz

No Haven't tried that, but both of the hoses you see in the picture are on the output side (so to speak). Draws coolant into the motor thru the bottom radiator hose (not visible in pic) then goes through the motor - and back into radiator thru the 2 top hoses shown in the pic.

I appreciate your input - keep em comin tho' - Thanks

TS1955

You say after 5 mins. of driving it gets hot. How hot does it get if you let it idle? Does it over heat? Reason I ask this is I am wondering, when you start driving and get the RPMs up the coolant is circulating too fast and not staying in the radiator long enough to cool down?

TS1955

DirkaDirka

This made me think of something else. What kind of water pump do you have on it?? Is it electric? Stock or high output??

zipper06

I'm thinking you need to put some restrictors in the 2 top hoses, such as you would if you had a thermastat or restrictors in the return to the radiator. i run a washer and restrict the flow to 1/2" volume return with a thermastat housing. In other words the water is not staying in the radiator long enough to cool down, it will never run cool. You need to slow down the flow so the radiator and fans can do their job.

JMO

Zip.

jerpazz

At an idle - after say 5 minutes of driving, you can literally pull up to a light - AS SOON as you are at a stop and it'll go up in temp from say 200 to 235 within 20 seconds. Because of this - as soon as it goes over 210 ish I'll just kill it and restart after the light changes.

Am thinking you may be right with restricting the flow :?: , but the hose dia is only 1/2" ID coming off the intake (X2 hoses) - the ID of the steel braided top hoses I mean.

jerpazz

Its a stock iron pump

jerpazz

Since I'm on break in with this motor - the hottest Ive let it get was ~238ish once. Scared the crap out'a me... sittin at one of our infamous 5 minute TX lights. I've never had it boil over

I will say - as soon as I start increasing the RPM - it'll slow down in it's climbing the temp. NOT stop - just slow down a bit - may take 25 - 30 seconds to go from 200 to 235 (vs. 15-20 secs)

Maybe I'll just block one of the 2 hoses off :?: and see what that does.

johnracer

Are you running the pullies that in your show off section pics? Looks like a really small crank pulley and a really big pump pulley. The pump may be turning waaaay too slow.....just a thought
Johnny