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I NEED HELP with radiator problems

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Old Dec 20, 2008 | 11:44 PM
  #1  
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From: magnolia ms
Default I NEED HELP with radiator problems

I came home from an afternoon drive and noticed a leak coming from the bottom of the radiator...... Well ok i found the leak and it is small. but I plan on getting a new one. The problem is that I drove it one afternoon cause the leak isnt that bad(I didnt go very far maybe a couple miles) The temp gauge went up so I stopped and shut it off waited then drove home fluid levels stayed the same, cranked it again and it never over heated. well I went out tonight to survey how to remove radiator when I noticed fluid pouring out of the radiator and radiator fluid was all over the top of the intake manifold. Could this be a stuck thermostat and leakey radiator or should I be concerned about other issues. Please help any help would be appreciated
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Old Dec 21, 2008 | 01:04 AM
  #2  
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for sure replace your thermostat as thats cheap security. use a new gasket or o-ring to make sure the seal on your housing is 100% as well as any sensors on your housing are ok .is your radiator copper/brass or aluminium. if its copper just have it flushed,soldered and pressure tested, it should be good to go.
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Old Dec 21, 2008 | 05:02 AM
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Could just be a leaky rad hose causing the problem. However, your overheating might be the result of several things. My 79 overheated last summer because the fan clutch went out. I didn't know it until I first replaced the t-stat and didn't help. The order of parts I'd try would be T-stat first, rad hoses second, water pump third and then fan clutch last. If none of these help then I'd start thinking about a blown head gasket or cracked block.
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Old Dec 21, 2008 | 07:31 AM
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Originally Posted by marshrat99
Could just be a leaky rad hose causing the problem. However, your overheating might be the result of several things. My 79 overheated last summer because the fan clutch went out. I didn't know it until I first replaced the t-stat and didn't help. The order of parts I'd try would be T-stat first, rad hoses second, water pump third and then fan clutch last. If none of these help then I'd start thinking about a blown head gasket or cracked block.
why would you want to replace the waterpump first before checking and/or replacing the fanclutch?

Waterpumps rarely go bad and if they do it's usually a bad bearing that causes the seal to fail and before replacing it it's easy enough to check to see if there are leaks coming from the seal around the shaft and if there.is any wobble or lateral movement of the shaft of the waterpump.

The fanclutch is even easier to check - simply bring the car up to operating temp than shut the motor off. The fan should stop within 1-3 revolutions. it it takes much longer than that or simply freespins the clutch is bad.

Typically, the waterpump is usually the last thing to have to worry about on the cooling system.
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Old Dec 21, 2008 | 07:41 AM
  #5  
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Originally Posted by 79_L82
I came home from an afternoon drive and noticed a leak coming from the bottom of the radiator...... Well ok i found the leak and it is small. but I plan on getting a new one. The problem is that I drove it one afternoon cause the leak isnt that bad(I didnt go very far maybe a couple miles) The temp gauge went up so I stopped and shut it off waited then drove home fluid levels stayed the same, cranked it again and it never over heated. well I went out tonight to survey how to remove radiator when I noticed fluid pouring out of the radiator and radiator fluid was all over the top of the intake manifold. Could this be a stuck thermostat and leakey radiator or should I be concerned about other issues. Please help any help would be appreciated
first of all, WHERE was the radiator leaking from?

As mentioned, if you are going to replace the radiator (Get a DeWitts!!) replace the t-stat at the same time, it's a cheap and easy replacement to stay safe.

When you pull the radiator also pull and carefully inspect both the upper and lower hoses. If they look ok, no rips, holes, dryrot of the rubber, etc and can reuse them but if ANY doubt about them replace them as it's MUCH easier to replace them with the rad out than fighting replacing the lower one after the radiator has already been replaced. DeWitts has the correct upper and lower hoses so if needed you can order them with your radiator.

A stuck or failed t-stat should not cause coolant to pool on the top of your intake. IF the source of the coolant on the intake was from the t-stat housing that could simply be a bad seal or gasket from the housing but it it didn't appear until the leaking from the radiator started it it could simply be coolant that was blown back onto the engine by the fan from the leak out of the radiator.

bottom line is you need to find WHERE the leak(s) are coming from before determining the problem and solution.
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Old Dec 21, 2008 | 11:40 AM
  #6  
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By all means, find the leak. You have good advice here. This is the time to replace any questionable hoses. Aftermarket radiators (DeWitts) are certainly a great way to go, if originality is not an issue. I do fine with a quality recore of my stock 68 Harrison. Generally speaking, if vehicle overheats at freeway speeds (load), suspect radiator capacity (or clogged). In traffic, suspect coolant flow or fan assembly. If the temp just keeps going up or takes a long time to reach operating temp. suspect thermostat.
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Old Dec 21, 2008 | 12:14 PM
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Originally Posted by marshrat99
Could just be a leaky rad hose causing the problem. However, your overheating might be the result of several things. My 79 overheated last summer because the fan clutch went out. I didn't know it until I first replaced the t-stat and didn't help. The order of parts I'd try would be T-stat first, rad hoses second, water pump third and then fan clutch last. If none of these help then I'd start thinking about a blown head gasket or cracked block.


We took our radiator, after I shopped around and the shop fixed it , cleaned and presuure check it for $50. Replace the hoses and the thermostat definitely when you have all this apart. Hopefully It will that simple. A friend of mine says if you are going to throw money at a car engine, at least start with the cheaper items first.If you do have to do the more major things at least the other stuff we be new too.
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Old Dec 21, 2008 | 12:15 PM
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Default thegazman

If you found a leak in the radiator the water on your manifold could be from the fan blowing water onto your engine. I replaced the radiator on my 79, L-82 with a Dewitts. If you loosen the fan shroud, disconnect all the hoses, etc. from your radiator with some assistance you can slide the radiator up and out. Repair the leak you can see before you start changing ever thing.
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Old Dec 22, 2008 | 07:20 PM
  #9  
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All of you have great advice, and I checked the fan clutch its good and the leak is at the bottom of the radiator (the botom spoiler that controls bottom airflow to the engine, the bracket came loose and stuck into the radiator, I pulled it out. Im going to go with pulling the the radiator out and replacing with new because we only have one radiator shop here and they charge more than 50 so ill just go new and then change the hoses and thermostat. The idea with the fan blowing the antifreeze on the engine is a good idea but Im thinking that It just might be the gasket. I dont know much about engines. I was affraid that like stated a crack or blown head gasket so I went out and checked all around engine and it seems to be setting only on the top. I thought at first that there could be some back pressure problems from something being damaged but like I said Im not a mechanic.The water pump should be fine cause I was told if it went bad then it would just leak. Ive been working very long hours or I would have posted earlier, Im kinda excited about working on it but I hate having to buy a 200 dollar radiator unless you all know were I can get one cheaper. THANK YOU for all the advice and time out of your day.
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Old Dec 22, 2008 | 08:21 PM
  #10  
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Sounds like you've narrowed it down. AutoZone has replacement copper radiators for $200, and they do fit correctly, unless you prefer aluminum. While you have things apart, double check your water pump. My water pump went south a few months ago, and as it started leaking, the fan blew coolant to the underside of my hood and the top of the engine. I removed the belt from the water pump pulley and checked the play by rocking the fan side to side. Mine had a lot of slop. It was so bad that after I replaced the water pump, my engine vibration at 70 mph disappeared. Your water pump is probably OK, but if any of these parts are original ones, you could possibly have radiator and water pump problems at the same time. It happened to me. Good luck.
Kenny
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Old Dec 23, 2008 | 10:37 AM
  #11  
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Default First clean system, then new rad

79 L82:
First ... if possible & practical ... before you pull old rad or add other pieces ... do a complete chemical cleaning of system including block ... not simply a flush but a cleaning ... then install new rad, t'stat, cap, hoses etc.
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Old Dec 25, 2008 | 10:18 PM
  #12  
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From: magnolia ms
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Thanks guys Ive decided to go all new rad,belts, hoses, themostat and water pump this should fix the problem. Sorry for the late post... Thanks alot for all advice.
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Old Dec 25, 2008 | 11:10 PM
  #13  
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From: Canastota Ny
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then you should be on your way to long years of service!! but just make sure you know where the coolant came from on top of the intake. alot of money invested only to find out you have a crack or loose bolt. keep posted! turn the lights on the christmas tree have a beer and worry bout it tomorrow!!
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Old Dec 28, 2008 | 12:13 PM
  #14  
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Ha Ha yeah. Im fixing to start another post on the fan shroud and electric fan cause my fan shroud was damaged when I got the car, the electric fan was tied up with a zip tie and didnt work so Im thinking of going with a better fan (not electric) without the shroud
thanks guys
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