Cooling issue

[Jrail721]

1991 Ranger. Mildly built 302. Have the 2 core stock radiator with a summit racing pusher fan and custom made fan shroud. No thermostat and a high flow water pump but over heats when I drive it. Is fine when sitting in the driveway idling but gets hot AF when I run it. I have an Edelbrock 750 on it now but and stepping down cause it seems like it drowning in fuel when I get on it. My thought is MAYBE the extra fuel being burned/or trying to is cause the engine to run hot, hence my cooling issue when I’m driving it and not just sitting idling. Thoughts? Suggestions?

 

[dvdswan]

I would think you would want a t-stat to control the water flow with a high flow w/p. IMO you're not giving the water time to be cooled by the radiator.

 

[Jrail721]

I started with a 185. Boiled over into the overflow. Stepped down to a 160 and did the same but took a little longer.

 

[dvdswan]

Is the w/p the correct flow direction? Is it setup for serpentine belt or v-belt?

 

[Jrail721]

I pulled the water pump to triple check it was the correct rotation. I have a CVF racing 8 rib belt system set up installed.

 

[dvdswan]

Ok, so your pusher fan, how is it wired? Is it blowing air out of the engine compartment or into the engine compartment? Which side is the fan on the radiator?

You think its a fuel issue and burning rich, do you see black smoke when you rev up the engine? Is the timing set correct? Unless your mixture screws are way out of whack, I think it would be a flow problem to cool the coolant down. Either coolant flow or air flow.

 

[Jrail721]

It’s a push/pull fan depending on how the fan blades are mounted. Currently I have it on the front of the radiator cause I have about 3/4” of clearance between the radiator and water pump pulley. I have checked it several times to make sure it’s pushing, which it is, just doesn’t seem to be enough. I built a shroud for it to help force the air through the radiator instead of it bouncing off and coming out of the front grill but it still seems to be coming out through the fan.
There is a little bit of black smoke that comes out of the exhaust when I get on it but nothing crazy.

 

[Sharky]

fan manufacturers recommend puller fans over the pusher type. the pusher fan mounted in front of the radiator also restricts air flow a bit.
if possible change it over to puller type on the engine side of the radiator. the shroud you made may also be hindering air flow as the pusher type
needs open space .

 

[RonD]

No thermostat will cause overheating, just FYI
A working thermostat can NEVER cause over heating, thermostat sets MINIMUM operating temp, so has nothing to do with maximum temp

Do you have the heater hoses connected, this is the water pump by-pass and needs to have flow all the time, even if you don't have a heater there needs to be a hose looped from intake to water pump

When its idling after warm up, which Rad hose is warmer, upper or lower?
If its lower then water pump is indeed spinning the wrong way
Lower hose should be 15-20deg cooler than upper hose, if colder then rad is clogged, if warmer then flow is to fast, which causes over heating, because, in effect, there is no radiator cooling

Fan is ineffective above say 35MPH, air flow thru rad from vehicle speed is more than any fan can provide
Fan is there for lower speed, and when stopped, cooling so you fan setup is most likely OK

So my guess is that you have an issue in the engine side of cooling system

Leave rad cap off and start cold engine
There might be a initial surge and some coolant might come out, but just one time
Let it idle and watch the the coolant level, should stay were it is, if its slowly rising and over flowing then you have a blown head gasket or cracked head, period
No mistaking that

You can do The Glove Test, to see which cylinder or cylinders are leaking

 

[Jrail721]

Thanks is for all the input. Figured it out today. Stupid ass fan was supposed to pushing the air but it wasn’t no matter if I reversed the fan blades. I reversed the polarity of the fan and that did the trick. Installed a mechanical water temp gauge, let it warm up to 190, cut the fan on and the temp dropped to 160 in about 2 minutes. Gonna put the thermostat back in it tomorrow.