walk me through swapping out my radiator

[txchainsawgogi]

So my engine keeps overheating and my radiator had a few pinholes, it leaks less now but still gets way too hot.

Basically I need to swap it out ASAP. What should I replace it with? Ideally I would like a radiator with more cooling power than stock.

I have a 78 c10 350 V8. Thanks!

[Irish_Alley]

Unless Your hauling trailers and stuff stock is all you need. If you want to run cooler you can change ur thermostat or add more straight water to the antifreeze.

[Lt.Del]

You can go stock.  I'd up it to 4 cores for just a few bucks more.  At a radiator shop you're only talking about $200.00

Chaning it out is very simple.  Take note how you remove the shroud and top metal bracket, and it just sits in there on rubber feet. 

 

[txchainsawgogi]

What about blocking off the heater core? Should I leave it alone...I only ask because my heater doesn't work anyway.

[beastie_3]

A new heater core is about 30 bucks. I would keep it flowing with fluid. What is wrong with the heater? Is it the fan?

[frotosride]

Here are a few cheap radiators but only cheap because of the price...
http://www.speedwaymotors.com/Speedway-Chevy-Universal-Radiators,3557.html
They are definitely cheaper than a stock replacement especially if you have an auto tranny, which is also the down side. You will also have to but a seperate cooler for the tranny
http://www.summitracing.com/parts/TCI-820500/
 Both are really easy to install and true you may not need all the cooling but the biggest obstacle to making power is heat so get a new thermostat to just cheap insurance.
If you need help and a literal walk thru just ask and i'm sure many will help.

[txchainsawgogi]

A new heater core is about 30 bucks. I would keep it flowing with fluid. What is wrong with the heater? Is it the fan?

I think its the fan... not positive.

[txchainsawgogi]

Yeah its an auto, so i'd need two. Would it be better just to upgrade to something new with more cores.

[Irish_Alley]

They do make bigger rad with a transmision cooler inside of it go to autozone and ask for a new rad they should ask how many Cores but I think if you go bigger you need new hardware maybe one for a 454 will be bigger than yours also

[Swims350]

you'd need two what?

As for blocking off heater yes you can do it it's easy shouldn't hurt a thing other then not having heat which sucks when the windows fog up, but if yours aint working doesn't matter. You can do this with one hose connected to both ports on the motor, or motor/radiator dpending on where they run to, leave the heater core nipples alone or plug them to keep dirt out.

Or you can put in pipe plugs for a more permanent plug. You can ake them out later though. if yours is on the rad. gonna have to get creative but most of the time when you buy one they have a cap on it so it's easy, just leave it on. it aint gonna help it cool more though, I'd look into the fan is it clutch fan? if so clutch may be bad, water pump may not be working good. Thermostat might be stuck or acting up, MY opinions a water pump is like $25, hoses upper or lower are $12 or so, thermostat maybe $5 and gasket is a buck, change the upper and lower hoses unless they are new like a year or so old, but inspect them closely, change the water pump, have the fan checked or run a flex fan maybe I always run them, just to be sure. Do you have a fan shroud? if not might want to look into one. Then change your raidtor out might look into a 2-3 row/core one my opinion 3 core or 4 if you got the cash at least 2 core.

Trucks usually run cool and easy to keep cool, if you're not towing or something. I had a 1 core in a 76 that kept a mild 350 stick shift cool, but the same setup in my monte carlo overheated ALL the time, same motor, same water pump, thermostat, same fan, same radiator. Only difference was a car and auto but it had it's own cooler not built into the rad. I never had a shroud on the truck either, but put one on the car and stiff didn't help. I bought a 3 core for it and a 7 blade flex fan and it ran cool all the time.

[Grim 82]

I wouldn't bypass the heater core. If the blower fan is not working, it is either the blower motor or an electrical problem, neither of which have anything to do with the plumbing of the cooling system. If your heater doesn't work it's not because of the heater core. If it's not leaking and its not plugged leave it hooked up. If it is leaking or plugged, replace it and hook it back up. You don't want to lose the extra coolant capacity. Just like how you can add an extra tranny cooler to keep temps down, think of the heater core as an additional little radiator, cause that's all it is.

You should be fine with a direct replacement radiator from the local parts store. If they have one with additional cores, get the biggest one that will fit in the mounts. Any new one will be aluminum which cools better than the copper brass ones. Since you will have the coolant drained, it would be a good time to replace any hoses that need replacing and put in a new t-stat. And definitely make sure that you run a fan shroud. My dad killed the original 305 in my pickup from running it without the shroud. I got a sweet 350 out of the deal though

[Swims350]

well I just said he can if he wanted since he asked. IMO the heater core shouldn't be needed to help cool the engine, it's just hoot fluid sitting in it unless the fan it on blowing it out. I had no heater in the monte carlo and it was bypassed for a few years while I had it and still is today and it ran cool.

By all means if you got all the stuff hook it up and have it work or fix it, it ALWAYS comes in handy winter or summer.

I could idle in triple digit high humidity summer heat in traffic all day long and never get past 180-190 and had a 180 t stat in the monte carlo. But trust me it needed a heater to defog the windows on cool nights or rainy days, not to mention cold mornings lol. Only reason I never hooked it up, was one the monte carlo box is huge, and ugly, finding a non a/c box is like finding oil or gold, and it's still big and ugly, and I needed everything, controls core, hoses, box everything. I was gonna retrofit something but sold it before I got to it. Now my bro in laws got it and is gonna have me hook up a heater sometime soon.

[Grim 82]

well I just said he can if he wanted since he asked.

And you are right, he can. I just wouldn't do that on one of my vehicles.
This was already discussed here:
http://forum.73-87chevytrucks.com/smforum/index.php?topic=16834.msg132571#msg132571

As far as the AC box you are looking for, have you tried a cutlass, parisienne, caprice, impala, delta 88, etc to see if any other GM cars would match up? I used to have an 83 with t-tops & 305

[txchainsawgogi]

Well this truck is a bit of a project, and not my daily driver. I've only driven it three times since I've had it. On the way back from picking it up from a small town 30 miles over it overheated due to the kid I got it from not understanding that an old radiator needs more than a 12oz bottle of ozarka in it.

That night I filled it with prestone and water. It got warm but never in the "red". A few days after I noticed a pinhole leak in it and used bar's(it always worked in my old fairlanes)... yesterday I drove it to the gas station and it was acting like I just drove it through death valley, pissin and steaming at every light.

Thermostat issue? I plan on swapping out everything mentioned here.

[txchainsawgogi]

Ok so tonight, before the sun set I took it out and drove it hard to try and get the temp up. Didn't budge past a notch above cold. WTH?