Not another air cooled question

JackDidley · JackDidley's Garage

I know you guys are all about air cooled but I have a water cooled question. Last winter the AC went out in my truck.I said to myself, self, you have to have AC by summer. So instead of a new compressor for the truck, I built a new truck with a new compressor. A 94 S10 with a 350 SBC, and big fat tires on the back. The air is very cold but the 350 is getting very hot at idle. My question is, do I need a better radiator or a better fan. Current radiator is from a 97 Blazer. Biggest stock type that will fit. Fan is a 17" flexfan, motor driven. Shrouds are in place. I'd like some opinions, fan or radiator ??
Pics of said truck below.

944 S2 · 08-31-2018, 05:34 PM

Fan running backwards. Electric I assume.

JackDidley · JackDidley's Garage

Quote:

Originally Posted by 944 S2

Fan running backwards. Electric I assume.

Fan driven by the motor, on the water pump. Correct reverse rotation blade for serpentine belt drive.

wswartzwel · 08-31-2018, 06:12 PM

Do you have a shroud? how close is the fan to the radiator... if it is happening at idle.. perhaps an electric fan would move more air at idle that the engine driven fan is currently moving.

manbridge 74 · 08-31-2018, 06:21 PM

It is important to have the fan sitting inside the shroud at the correct depth to pull the air without bypass.

id10t · 08-31-2018, 06:23 PM

Is your fan capable of moving enough CF/M air flow via the engine power, or is the only reason it doesn't over heat at speed is because of air flow at speed? Especially when the engine is running at low RPMs... like a stop after running at higher RPMS for a bit (and getting hot).

I have seen the temp gauge on my 356 be dead center, sit at a stop light in the florida sun for a few minutes and its moved noticeably hotter and more than a hair. Get going again, couple of minutes at 25+ and it drops back down again.

If you want to geek it out, I'd look at extra fans for air movement, and set them up so they can run for a few minutes after engine is turned off.

pavulon · 08-31-2018, 06:26 PM

Can you easily swap in a non-flexible fan and/or smaller fan pulley to see what happens?

JackDidley · JackDidley's Garage

Shroud is in place. Fan is 3/4" from radiator. No room for adjustment on the fan. Motor is back, almost touching the firewall. Electric fan may be the fix. Or a bigger radiator ?? Just looking for opinions, fan or radiator ?? Maybe a bigger radiator and an electric fan ?? I do not have much room to work with.

VincentVega · 08-31-2018, 06:29 PM

I had one in the 90s, loads of fun. Foggy memory but IIRC I had a ~90 1500 chevy radiator. Was pretty thin but wide. I added a higher flow pump at some point, used a standard summit flex fan too. Now you can get a bolt in custom radiator, I would go that route. Superior is one I think, was thinking about another one of these recently.

JackDidley · JackDidley's Garage

I have a high flow Corvette pump. General consensus seems to be the fan. Electric puller will be a tight fit. I think I have 2 1/2" between the water pump and radiator.

manbridge 74 · 08-31-2018, 07:10 PM

Sounds like the fan is to deep inside the shroud. Can you get a low profile water pump for this engine?

Electric fans that move equivalent air are expensive. You will need a puller and a pusher with the puller being more efficient so it should be the largest size possible.

JackDidley · JackDidley's Garage

I looked at the Superior option. Nice. $350 but nice. It would be worth $350 if I knew for sure it was the fix. Have to keep looking at options.

pwd72s · 08-31-2018, 07:33 PM

https://becool.com/

fintstone · fintstone's Garage

Thermostat.

manbridge 74 · 08-31-2018, 08:27 PM

T-stat going bad usually causes worse overheating under load, though not a bad idea to replace.

JackDidley · JackDidley's Garage

Quote:

Originally Posted by fintstone

Thermostat.

Had a 190* in it. Took it out today just to see what happened. No change.

JackDidley · JackDidley's Garage

Quote:

Originally Posted by manbridge 74

Sounds like the fan is to deep inside the shroud. Can you get a low profile water pump for this engine?

Electric fans that move equivalent air are expensive. You will need a puller and a pusher with the puller being more efficient so it should be the largest size possible.

The fan may be too deep. I do have a short pump, no wiggle room. May try fans first . Then a radiator if needed. Fans, $100, radiator, $350. Did I mention, I get a $3000 bridge in my mouth in 2 weeks and the Porsche needs a clutch and flywheel ??

fintstone · fintstone's Garage

Then timing is retarded.

VincentVega · 08-31-2018, 08:39 PM

I know you asked fan or rad and I'm sure this isnt what you want to hear but to me its both. Check the inlet and outlet of the rad with a IR thermometer. Good delta? If not, try a box fan in front, make any difference? Dont mean to be all over the map but I'm tired.

Timing good? Not too lean? I had exhaust issues at first, that heated up the engine bay quite a bit too.

Summit sells a rad too

Radiator Style: Crossflow
Overall Width (in): 30.750 in.
Overall Height (in): 15.875 in.
Overall Thickness (in): 3.125 in.

JackDidley · JackDidley's Garage

Quote:

Originally Posted by fintstone

Then timing is retarded.

Possible. Will check Saturday.