Did I choose the wring radiator?

[Greasey Harley]

I recently built a 350 for my k10. Bumped the compression to 9.5:1 and added some mild mods.
I installed a 4 row radiator and corresponding shroud. Problem is, i just went outside to warm up the truck (28* F right now), and after about 8 minutes, the heater is still blowing luke warm. it has a 195* T-stat. Is this what I can expect from the bigger rad? I guess I never had a small block with a big radiator, at least not one I drove in the winter.
Thinking about covering part of the radiator or reinstalling the original radiator. This is a hunting rig and heat is important.

What's your $.02?

[truckster]

Cardboard is cheap. Give it a try. If you get the desired result, you can do something more permanent.

[b454rat]

8 minutes isn't very long. Let it run lil longer, be warmer.

[truckster]

Originally Posted by b454rat

8 minutes isn't very long. Let it run lil longer, be warmer.

I missed that part. I agree, run it a little longer before you try the cardboard.

[cadillac_al]

By the time you drive 3-4 miles it should be pretty hot. You may have a defective thermostat. I wouldn't think a big radiator would make that much difference. Caddys have big radiators.

[Greasey Harley]

I'll give it a chance before I do anything hasty ...I guess. Haven't even really driven the truck. Still got some tuning and engine break in to finish. I like to warm my truck up on cold mornings and I am not exactly a patient person. Maybe i should have gotten a fancy new truck with auto start.

[sweetk30]

i have a 3 core in mine and 195* t-stat and it takes a bit .

thats a lot of cast iron and 4+ gal of coolant to get warmed up .

[Captainfab]

It is going to take a lot longer that 8 minutes for the heater to blow hot air with a small block and a 4 row core radiator. Especially when the temps are below freezing. Do you have a clutch fan or a direct drive fan?

[Greasey Harley]

Originally Posted by Captainfab

It is going to take a lot longer that 8 minutes for the heater to blow hot air with a small block and a 4 row core radiator. Especially when the temps are below freezing. Do you have a clutch fan or a direct drive fan?

Dirrect drive fan.
I might just have to use my other truck for commuting in the snow.
My point was that I don't plan on towing anything, so the original rad would have probably been sufficient, and the heater would have heated up quicker. It's all good, I'll stop being a wuss.

[sweetk30]

1 of my old trucks had a built 400sbc that would scream . . . i had a 3 row copper/brass in it . i had a mix of fan shroud / no shroud / 3" body lift and streched shroud . i even had clutch fan and solid fan . . . she always was 200-205 range .

a good system with good parts dosnt need massive rads in them all the time . sometimes to much is a bad thing to have .

[SunSoaked]

Originally Posted by Greasey Harley

I'll stop being a wuss.

That's usually the best option.

When my wife rides along in my bouncy, noisey 85k20 she always has something to complain about. I give her the death stare and remind her that walking isn't crowded. That usually fixes it.

[WorkinLonghorn]

The radiator has NOTHING to do with your problem. No coolant reaches the radiator until the thermostat begins to open at ~ 191°-192°.

Check your thermostat. Check if the coolant is actually hot and your heater core is not being delivered adequate hot coolant.

Feel the top hose to the radiator and if it is gradually getting warmer but never hot, then your thermostat is stuck open or is missing.

[SunSoaked]

Originally Posted by workinlonghorn

the radiator has nothing to do with your problem. No coolant reaches the radiator until the thermostat begins to open at ~ 191°-192°.

Check your thermostat. Check if the coolant is actually hot and your heater core is not being delivered adequate hot coolant.

Feel the top hose to the radiator and if it is gradually getting warmer but never hot, then your thermostat is stuck open or is missing.

x2

[Captainfab]

A thermal clutch fan may help some. For a mild 350, a 3 row core would have been sufficient. What does your temp gauge say after 8 minutes of running?

Originally Posted by Greasey Harley

Dirrect drive fan.
I might just have to use my other truck for commuting in the snow.
My point was that I don't plan on towing anything, so the original rad would have probably been sufficient, and the heater would have heated up quicker. It's all good, I'll stop being a wuss.

[67 Burb]

Originally Posted by WorkinLonghorn

The radiator has NOTHING to do with your problem. No coolant reaches the radiator until the thermostat begins to open at ~ 191°-192°.
Check your thermostat. Check if the coolant is actually hot and your heater core is not being delivered adequate hot coolant.
Feel the top hose to the radiator and if it is gradually getting warmer but never hot, then your thermostat is stuck open or is missing.

I agree. (And up here in Manitoba we know about COLD!) I just started reading this discussion, and was wondering why nobody brought this up until I got all the way down to WorkinLonghorn's post which was post #12.

On my Burb, the heater hoses get too hot to hang onto before the upper rad hose even starts warming up. Greasey Harley said he has a 195° thermostat, so his heater hoses should be good and hot before the t-stat opens.

[Dead Parrot]

Double check that you are feeding the heater core from the intake manifold port and returning to either the water pump or radiator.

If your timing and idle mix are good, you really aren't burning much gas at idle and it will take a while for several hundred pounds of iron, steel and coolant to get to temp.

You have plenty of cooling power, get a standard duty fan clutch. A lot less fan roar at speed.

A better test is go for a 5 to 10 mile drive. Should be plenty hot after that. Assuming the rest of the heating system is good, once hot, it should run you out of the cab with the fan on anything but slow.

[garyd1961]

Originally Posted by workinlonghorn

the radiator has nothing to do with your problem. No coolant reaches the radiator until the thermostat begins to open at ~ 191°-192°.

Check your thermostat. Check if the coolant is actually hot and your heater core is not being delivered adequate hot coolant.

Feel the top hose to the radiator and if it is gradually getting warmer but never hot, then your thermostat is stuck open or is missing.

x3

[AcampoDave]

If you are using the Mr. Gasket high performance type of thermostat, beware because they are designed to allow a small percentage of coolant to pass thru even when closed. I used to use one in here in California and wondered why I couldn't reach operating temperature in winter. A quick Google search revealed the answer. I pitched that therm in the trash and put in a regular house brand from the parts store and problem solved.

[garyd1961]

Originally Posted by AcampoDave

If you are using the Mr. Gasket high performance type of thermostat, beware because they are designed to allow a small percentage of coolant to pass thru even when closed. I used to use one in here in California and wondered why I couldn't reach operating temperature in winter. A quick Google search revealed the answer. I pitched that therm in the trash and put in a regular house brand from the parts store and problem solved.

This^ especially if you are using a high volume water pump. A high volume water pump will push coolant right pass the Mr Gasket thermostat.

[68gmsee]

I agree with above posts. Takes more than 8 minutes in real cold weather to warm up the engine coolant to operating temp. Even here in Texas where it rarely gets down to freezing it takes that long just to warm it up in winter.

Recommendations to replace the t-stat if it never reaches operating temp is correct. May not be closing all the way. My brother in law recently installed a local auto parts t-stat on his newer truck and it has trouble reaching operating temp. Computer keeps posting a low temp error code.

Also the posts about driving a few miles and/or replacing the fan with a clutch fan is also correct. It will help warm up faster in both cases.

[Greasey Harley]

So I did some tweaking and tuning, and am feeling better.
I got the electric choke adjusted, and raised the high idle on my Q-jet.
With these adjustments, the truck seems to warm up way faster.
It was 24* F this morning.
After about 5 min, my windshield was about half defrosted and the heater was starting to blow warmish. It will be at least a couple more weeks before I drive the truck regularly, but I think I'm pointed in the right direction.
I always second guess myself when I go changing stuff around.