73-87chevytrucks.com
73-87 Chevy _ GMC Trucks => Engine/Drivetrain => Topic started by: txchainsawgogi on July 28, 2010, 09:13:23 pm
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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!
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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.
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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.
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What about blocking off the heater core? Should I leave it alone...I only ask because my heater doesn't work anyway.
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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?
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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.
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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.
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Yeah its an auto, so i'd need two. Would it be better just to upgrade to something new with more cores.
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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
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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.
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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 ;)
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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.
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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
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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.
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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?
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I got a brand new all aluminum radiator off ebay for under 260 and it came with 2 12in electric fans. It is a direct replacement, not a universal type, so it fit perfectly. It came with a internal transmission cooler and it also has a spot to put in a temp gauge sender if I ever need one.
If you run a transmission cooler, spend the extra money on a stacked plate type, not the cheaper tube and fin. It cools better. I run one, after it goes through the radiator.
I would keep the heater core hooked up. We can help you fix your fan, or otherwise diagnose it. It can usually be something simple to fix the fan.
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yea done checked all of that as well as every other monte, regal, cutlass, grand prix, malibu owner out there to find a non ac box. I'm gonna use a 73-87 truck no ac box and retrofit it for him. Or let him buy a sumit mojave heater self contained unit.
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I found the same radiator+fan combo deal. How do I hook up the fans? I might just go with an aluminum rad, new water pump and thermostat for now...then get a fan down the road.
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http://cgi.ebay.com/ebaymotors/3-Row-Aluminum-Radiator-Chevy-GMC-Truck-1973-80-Fans-_W0QQcmdZViewItemQQhashZitem45f4476e3dQQitemZ300451065405QQptZMotorsQ5fCarQ5fTruckQ5fPartsQ5fAccessories#ht_5351wt_1140
Got my eye on this one, and a new thermostat, and maybe a new hi flow pump. I want cooling overkill haha.
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T-stat stuck open? Or no water going past the gauge sensor?
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I found the same radiator+fan combo deal. How do I hook up the fans? I might just go with an aluminum rad, new water pump and thermostat for now...then get a fan down the road.
I was having trouble finding the female ends for the fan plugs, so all I did was get two GM alternator wire extensions at the parts store. The wires are large enough to carry the load for the fans. I cut the fan plugs off, cut the extensions in half and wired it all up.
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I shouldn't have any power drain issues with them right?
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Not unless it is still running hot. I got a adjustable thermostat kit that turns the fans on when it reaches a certain point.
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Not unless it is still running hot. I got a adjustable thermostat kit that turns the fans on when it reaches a certain point.
Where do I find a kit like that? Sounds like it has the potential to be difficult to set up haha
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I got mine at summit. It is adjustable so you can have the fans turn on at 180, 190, 200, what ever you want. It just takes a screw driver to turn. Ill look for the one I bought and post the link. Its not hard to wire: 12+ wire, thermostat wire, ground, and fan wires. It also has wires to hook up to the AC if you have one.
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How do I flush things out before I hook up the new radiator? Literally just use a hose or is there a better method?
Also, any additives suggested when using a brand new rad?
Oh yeah and how do I know what temp thermostat to use?
I should be getting my new one on wed., I'm super excited!
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A hose is prob the easiest way to flush..just open the drain plug and get all the coolant out.You can take the coolant to most autoparts stores and they will dispose of it for you. then just take the cap off and put the hose in. let it flow and watch the color of the water coming out this will tell you when a good time to stop would be.
Just go with a 160* stat it will not only runn cooler but as you know that means more power...
Remember that most of the wiring kits for the fan/s that you buy will have a remote power wire so make sure you splice it into a wire or terminal that is only on with the key.
here's a good additive to help cooling and it's a trusted and proven brand. http://www.summitracing.com/parts/RPO-01600/
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Royal purple vs. Redline?
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who cares, for me if it ain't purple it doesn't flow..just pick one.
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Are you trying to flush the system to get rid of debris, or to get rid of old coolant? I really wouldnt use tap water. Supposed to use distilled water. 160* isnt going to give you any benefits. If you have a cooling system that works properly, 180* is fine. Come winter, it will take much longer to warm up. The factory never ran 160*.
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Well I'm installing a new radiator and most likely a water pump, so I wanted to flush all the crap out of the system...debri and old fluid. I hear its "recommended" to flush everything out of the engine when putting in a new rad. Tap is my only option unless I want to spend money to get the entire thing done for me at a shop.
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Get some prestone rad flush. Theres two kinds, the one where you drain the coolant and fill with water and the cleaner and drive for 600 miles or the one where you fill with water and the cleaner and idle for 20 minutes. I've done both and am satisfied with the results. if you want it clean and cleaned good, take it to a 10 min oil change place or something along those lines. Here in my town, its like 130 bucks to clean it out. I've never done it, but it's worth a shot as well
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What size is the core on our trucks? Are they the same from 73-87? I'm looking for a replacement for the single-core I have, which I think may have been the original from when it was a 6 cyl. but not entirely sure. I know I have an 73-80 frame on my truck but I don't know what year of rad. I'm looking for something to be capable of towing a 5500-6000 lb trailer.
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the Rad is truck specific. Depends on engine, transmission and drive train.
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I would take Irish's advice and go to autozone and get a new 4 core radiator. They are around 130 bucks. Then I would install a 180 degree thermostat. Check your hoses and make sure they are still firm also. Sometimes the bottom radiator hose gets sucked flat and causes overheating problems.
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Autozone was useless and didn't have a 3 or 4 core anywhere near 130. I bought one off ebay and I'm going to install it Friday. Hoses look fine...def need a new thermostat. I might get a large push fan in chrome and a cheaper plastic puller. Next is the ignition system.
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Autozone was useless and didn't have a 3 or 4 core anywhere near 130. I bought one off ebay and I'm going to install it Friday. Hoses look fine...def need a new thermostat. I might get a large push fan in chrome and a cheaper plastic puller. Next is the ignition system.
You want to get a chrome electric push fan? I think it might be distracting from the front of the truck. I would just get two black pullers, IMO.
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I kind of wanted something behind the new low pro grille I plan on getting... something flashy, but hidden...and functional. For now I'm just doing pullers. Once I get the grille I'll measure for clearance and that will help me decide.
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Hey guys... how much fluid should I expect to be putting in this empty system?? Also, how hard is it to replace the water pump?
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Autozone was useless and didn't have a 3 or 4 core anywhere near 130. I bought one off ebay and I'm going to install it Friday.
a city like Austin has no radiator shops? It should have at least 5. I'd never go to the 'zone for something like that. Go to the guys who know radiators. Got yellow pages?
Looks like you found one on the internet--hope it fits and shipping didn't hurt it.
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Well, oil (or trans fluid) in the drained rad fluid. So that's great. Head gasket...or?
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Is the engine oil a milky color?
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Milky, no. Just dirty.
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If you think its transmission fluid, it could be the cooler inside the radiator.
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Oh yeah...there was also a rat skull and jaw bone in my SEALED overflow tank.
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Nice. Count on at least 2 gallons
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Apparently it wasnt sealed! Acutally, I put the rat skull in there when you werent looking.
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The weirdest part is that I found rat bones, missing a head, stuck inside one of the a/c vent tubes. How did its head make it to the radiator?
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pop the top off the master cylinder, i think his leg bone is there.
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I'm sure there are more bones as well as mud dobber nests I haven't found yet. That's what you get for buying a 700$ farm truck!
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But
I'm sure there are more bones as well as mud dobber nests I haven't found yet. That's what you get for buying a 700$ farm truck!
My friend, you missing the best part of buying an old truck and getting it right. That's the kind of truck a lot of us in here started with. Mine still kind of looks like that on the outside. It was a $750.00 delivery truck. But I've put a lot of work and money into it. It's just not all paint and body. Mine is now 100% mechanically sound. If you do not loose interest in it and sell it, it will turn into a thing of pride. Pride of ownership, pride in knowing you did it yourself. If you keep going with it, it will then turn into something that quietly begins to consume your life, your free time and a large portion of your mind. Next, you will have 2 or 3 more in various states of disrepair parked in your yard. If you're married, this will surely be to the delight of your wife. Yes my friend, you are just embarking on a journey that will be 50% hobby, 50% compulsion and 50% mental illness. ::) I love it!
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When I went to replace my thermostat, the housing snapped in half. Awesome! Bought a replacement...much thicker and heavier than the oem one.
I can't seem to get the little three prong vacuum thing off the top. What's it do? What's it called? Do I need it?
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Do you Need it no. What's it called idk. If you have all your vacuum line setup I would try to get it off. If you don't have emissions just forget About it most after market ones don't even have one
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So just cap off the lines that went to it?
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it's a thermal vacuum sensor for certain vacuum lines. it completes vacuum routes for certain smog stuff when the engine warms up.
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it's a thermal vacuum sensor for certain vacuum lines. it completes vacuum routes for certain smog stuff when the engine warms up.
I always wondered what it was. However, I always knew that it was worthless junk some funny lookin' fella' with weird lookin' hair and large framed glasses thought up. I HATE the o-ring chrome housings that are $10 at local automotive stores. Fricking worthless. Ordered a housing for $11 (from local auto. store) for a 1969 Chevrolet Camaro with a 5.7L engine (because I knew that it would be the kind of housing that made sense). Flat on the bottom, no extra wires, no extra hoses, just plain, simple, nice looking, and leak-free.
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My aftermarket thermostat housing has the o-ring but I still put some sealant on it anyway.
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Hate to jump in and ask a dumb question but interested in one of these ebay radiator setups. Which of these would fit in my 1986 GMC 1500?
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This is where I got mine
http://stores.ebay.com/PERFORMANCE-COOLING?_rdc=1