How hot is too hot for a 351W?
 

Hmmmm... Our '50 F1 has a mild cam 351W with Edelbrock Top End & Carb - 400 hp. We are running a Derale electric fan & a 195 degree stock thermostat. Our truck runs at 180 - 190 degrees on the highway no sweat but in town it's making me nervous - popping up over 210 degrees & beyond when stopped in traffic or at a light. It's hot here in Texas - but how hot is too hot for this old truck?

Possible "Fixes" we are contemplating: Please let us know your experience in cooling down engines & any helpful thoughts.

Easy Stuff:
o A product called "Water Wetter" - some sort of voodoo that makes the water molecules cool more? ($20)

o Drop the thermostat down to 180 degrees - Go with a Robert Shaw High flow Performance thermostat. ($30)

o Eliminate all gaps around the Radiator with high temp weatherstripping from McMaster.com. ($20) (I'm not sure we have the air dams others talk about - our truck was pretty much a basket case to start with).

o Re-set Timing & Carb. settings to ensure it's not too far advanced or too lean.

Harder Stuff:
o Current Derale Fan is rated at 2400 CFM. Move up to a Black Magic Extreme Fan 3300 CFM. ($300). Or a Lincoln Mark 8 Fan at 4,000 CFM.

o Eliminate the Trans Cooler.

o Wrap Headers with Header Wrap to drop engine compartment temps.

o Go back in and look at the Head Gaskets to see if they are installed backwards & are blocking water flow. (We had the Heads off when our engine crapped out due to non case hardened push rods grrr..).

Looking for any good ideas... We'd like to run the A/C it's HOT over here but it's overheating already....

Ben in Austin
1950 F1

Ben if its only getting to around 210 220, I personally believe that is not too hot, if it's only when you're stopped in traffic. Just for example straight water boils at 212 degrees at sea level, if you run a 10 pound cap you raised your boiling point by 30 degrees 3 degrees for each pound of pressure. Which means the engine will not start to boil over until it reaches 242 degrees. So unless you are going higher than say 220 I do not feel you have a problem and I've personally ran vehicles to 220 degrees and never had a problem.

As to some of your possible issues, if your head gaskets were backwards it would be constantly overheating and it would never be close to being normal. As far as timing and carburation, those are things that you should make sure are done correctly regardless of your heating issues. Water wetter is said to be a big improvement and I am planning on putting some in my motorcycle for its benefits.

I would use a 180 thermostat and the water wetter .

Thanks Dave & Scott,
I understand the water boiling # of 212 degrees & that the boiling point is higher with antifreeze & pressure - it still just makes me nervous. In normal cars you just see H & C but no numbers so you don't fixate on them.

I'd really like to stay under 200 degrees & be able to run A/C. It just seems like a spiky hot engine - I'd like to smooth it out a bit. I couldn't imagine trying a stop & go parade in it.

I'll try timing/carb. & the water wetter product & report back. We also hard wired the fan to come on with the ignition as we were blowing fusible links regularly. I'm wondering if that is keeping it at the low 1800 cfm speed & it's never getting to the higher 2400 cfm... Hmmmm..

Has anyone run this water wetter product? Any issues?

Thx Guys

Ben in Austin

Hi Ben , the fact that you say it's fine temp wise while driving to me means it's an air flow problem .
I doubt timing or carb would be the culprit as these would cause more problems at speed . .
I would try the lower temp t/stat and the water wetter .
Then if no joy , try a thermostat control for the fans set at 180 , but make sure the fans are wired through a relay .

Agreed it may be an air flow problem if it is only an issue when sitting in traffic, can also be water flow depending on the water pump design.
First thing I would be looking at is the cooling fan and shroud situation, I stick with OEM electric fans because I know they are designed right. Not sure what the derale fan flows or how big it is compared to your radiator core? Also is your fan a pusher or puller? Have you made sure it is spinning in the correct direction?

Hey Dave,
We've got a Derale 2 speed electric fan. We "rigged" it a bit after blowing (2) fusible links in 6 months. It's currently hard wired to come on with ignition. I'm thinking that this might be causing more problems than it's fixing - Not sure I'm ever getting to the higher 2400 cfm fan speed with this hard wire set up.

The truck drives fine. We took a load of college stuff up to Waco (100) miles last week & it stayed at 180 - 190 degrees. In town it's a little dodgy - it heats up quickly to 210 & higher if you are stopped for any length of time.

I just thought I'd try to tackle this once & for all. I'd like it to be rock solid in the Texas heat so we can run the A/C. It's brutal right now.

Ben in Austin

Do you have a picture of the fan and radiator setup?
If you put the truck in neutral and bring up the idle speed does it help any?

First place I would check is the radiator followed by the fan shroud setup. If you are running an aluminum radiator and do not have it grounded with bonding straps then there is a possibility for corrosion that will reduce how effective the radiator will be at cooling.

Hey Charlie,
The radiator is an aluminum American Racing brand I got from Summit - pretty new. We do have a transmission cooler running through it as well.
The electric fan covers the back of the radiator with a (1) piece plastic set up with the fan in the middle of it - there is no other shroud on there but it looks like the electric fan serves that purpose (?).

Dave - I'll ask my son Zack if he's tried elevating the revs & what happened. (He's still sleeping - must be nice).

Ben in Austin

No reason for a 195 stat on a non-emission engine. Changing to a 180 is simple and cheap. If you don't see a significant change, then it will point to the radiator as a problem. I'd forego the water-wetter.

Running the fan all the time uses a lot of power. Is it literally wired direct to the ignition switch? That's a lot of load on the switch. A proper thermo-switch, with a relay, is worth the trouble.

Hey Ross,
Thanks - I'll go with the 180 degree thermostat. What temp settings would you have with the (2) different fan cycles come on?

Ben in Austin

Not sure what you mean by "2 different fan cycles"? Is it two-speed?

Turning on A/C should turn on the fan, to hi-speed. I'd vote for a ON temp switch of 200 deg. If it's a 2-sp fan, add 10-15 deg for hi-speed. Lots of disagreement on where the best place to put the thermo switch is. Some say on the radiator inlet, some on the outlet. Your ON setpoint depends on where you put it.

Hey Ross,
Yep it's a 2 speed electric fan made by Derale. Currently the thermo wire goes over to the very bottom of the radiator on the passenger side.

Ben in Austin