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Need help soldering a radiator. Pages: 12

FrankD. on Sun September 30, 2007 11:08 PM User is offline

Year: 1975
Make: Chevy
Model: C10 pick up
Engine Size: 350
Refrigerant Type: none

Need help soldering a radiator.


The other day I replaced the water pump on my 75 Chevy truck. When I was through the lower return radiator fitting was dripping and the upper fitting had a slow seep.
After pulling the radiator I discovered I only had lead free house plumbing solder and zinc chloride flux paste. I sanded and scraped and wire brushed the fitting and used a propane torch and the house solder.
The solder flowed better than I thought it would but after the test drive the upper water input fitting on the drivers side is seeping again. This is about the third time solder on the upper supply fitting has cracked and before I used 50/50 solder and acid flux.

Is there any way I can repair this upper radiator fitting so it will not crack the solder again?






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FrankD.

NickD on Mon October 01, 2007 7:29 AM User is offline

Lots of industry having problems with lead free solder, damn stuff doesn't stick, my house was picked by the EPA since it has copper with lead soldered joints, but always showed zero ppm lead content, was recently kicked off because I recently installed a water softener which doesn't remove lead anyway, think I was kicked off because I wasn't showing lead in my water.

Still can buy 60/40 rosin core solder, but have to pay through the nose for it now, more of this EPA BS, that is what I use. But you cannot expect solder to have strength if you have a tight hose vibrating back and forth stressing that radiator joint. It was in the 50's and early 60's that it took a strong man with the help of a small boy to pull a radiator, sometime in the late 60's, just took two weak fingers to pull a radiator out, GM quit using brass plate and switched to brass foil. Had to form brackets out of flat steel to provide additional support for the radiator hoses to relieve the stress that shaking engine would put on them and flush and change the anti-freeze no longer than two years as acid builds up rotting holes in the radiator to get them to last. Well at least extend their life until the body rusted away, you may have to do the same, look for your stresses.

iceman2555 on Mon October 01, 2007 11:21 AM User is offlineView users profile

The probable cause of the continued leak in this area...may not be the solder or the flux...it probably is dirt or debris captured between the fitting and the tank. Simply cleaning the outside does not remove this contaminant. All contaminants must be removed for the solder to hold.
Suggest to remove the rad....using your torch apply sufficient heat to melt the solder joint on the fitting....completely remove the fitting from the tank....use a pair of pliers...it will be hot....cool the fitting....using a wire brush or wire wheel...completely clean the brass surface...take it down to a shinny brass scheme.....apply flux and reheat...apply a small amount of solder to the fitting...while heating this solder...use an acid brush to completely cover the inlet fitting with a light solder base coat....this coating would be in the fitting to tank contact area.....use the same principle to clean the tank fitting area....be careful not to use excessive heat and break the tank to header bond....another problem all together.....cool both areas....insert the fitting back into the prepared area of the tank....and resolder.....should hold at this time....
It is impossible for solder to hold on a dirty or contaminated area..
Good luck with the repair......

-------------------------
The strongest reason for the people to retain the right to keep and bear arms is, as a last resort, to protect themselves against tyranny in government.
Thomas Jefferson

mk378 on Mon October 01, 2007 1:25 PM User is offline

I agree with Iceman, take all the solder off down to bare metal and see what you have. If the tank is cracking out away from the fitting it's likely to keep going further and the only real cure is a new radiator. The type of solder or flux used is not very important as long as it gets full wetting of the brass.

FrankD. on Mon October 01, 2007 2:22 PM User is offline

Thanks.
The solder joint has a hairline cracked ringed around the fitting just like a bad solder joint on a circuit board.




-------------------------
FrankD.

iceman2555 on Mon October 01, 2007 3:07 PM User is offlineView users profile

If the crack is in the solder joint...this can be repaired with soft solder...however, if the crack is actually within the brass tank itself....soft solder will not hold this...it must be repaired using silver solder..this is the only method to insure a true repair.
The down side of using this method is the amount of heat necessary to melt and flow silver solder...if not adapt at using high heat in a confined area...best bet would be a radiator shop or search the net for a replacement unit.
Considering the age and possible condition of the rad..this may be the more advantageous path.

-------------------------
The strongest reason for the people to retain the right to keep and bear arms is, as a last resort, to protect themselves against tyranny in government.
Thomas Jefferson

bohica2xo on Mon October 01, 2007 5:10 PM User is offline

A NEW radiator for a C10 w/5.7L 4v & A/T is only about 120 bucks. I would not waste the time on a 30 year old leaker.

B.

-------------------------
"Among the many misdeeds of the British rule in India, history will look upon the act of depriving a whole nation of arms, as the blackest."
~ Mahatma Gandhi, Gandhi, An Autobiography, M. K. Gandhi, page 446.

mhamilton on Mon October 01, 2007 7:46 PM User is offlineView users profile

Quote
Originally posted by: bohica2xo I would not waste the time on a 30 year old leaker.

Do old radiators really have diminishing returns as far as repairs go? I ask because I've had my 30 year old radiator repaired, only to have it leak again a month later, and it looks like it's now springing leaks within the core. I was going to have it repaired again, but if its just going to keep repeating this pattern, I will also go with a new rad.

NickD on Mon October 01, 2007 7:47 PM User is offline

The radiator in my 70 Buick Rivera went out when it was only six years old with 60K miles on it. Took it to a radiator guy I knew back then that was good, really good. Said nothing left of it to fix, have to buy a new one, and in this case, aftermarket was much better than OE.

I know Frank better than that to suggest he was trying to solder over a pile of corrosion, if he has something left to solder, can attempt to remove the stress off the hoses and just resolder it and get a few more miles out of it. Not only had problems with the 70, but with the 73 and 78 Caddy radiators, with a 76 Pontiac thrown in, all junk, just assumed Frank's radiator also from the era is junk from the factory.

HerkyJim on Tue October 02, 2007 2:34 AM User is offline

Quote
Originally posted by: mhamilton
Quote
Originally posted by: bohica2xo I would not waste the time on a 30 year old leaker.



Do old radiators really have diminishing returns as far as repairs go? I ask because I've had my 30 year old radiator repaired, only to have it leak again a month later, and it looks like it's now springing leaks within the core. I was going to have it repaired again, but if its just going to keep repeating this pattern, I will also go with a new rad.

Definitely, but...I had the original radiator from my '72 Plymouth recored 3 1/2 years ago. It had 185,000 miles. Radiator guy said core was shot. I had found a crack in the lip of the filler neck my self. He found leaking trans cooler tube in the lower tank when he was checking it out.

New three-rows core; new trans cooler tube; and new filler neck; plus labor $188.75. I could have gotten an "hecho in Mexico" new one for less money, but I think I have a better radiator this way. Has been 40,000 miles plus since the recore and cools like a new one and doesn't leak a drop.

Copper prices up since then. He quoted me $250 for a three-rows recore on my '65 Chevy radiator last summer.

My $0.02

NickD on Tue October 02, 2007 6:20 AM User is offline

Interesting about your 72 Plymouth, I picked up an 80 Plymouth Horizon for my kids to drive to college, the radiator was so badly scaled up, had to remove the tanks to rod it out, but it didn't leak, lasted a long time. Relatives were driving Chrysler products back then, had problems with everything else, but not the radiators, LOL, maybe should have put a Chrysler radiator in a GM product.

Did a very unAmerican unpatriotic thing by buying Hondas, finally had cars around here that we could drive without fixing them every five minutes. But apparently not the only one, because Chrysler was wondering why they were going under and GM and Ford were wondering why they were going broke. Ha, remember talking to the Honda salesman, said there is plenty of room in the Honda, turned around and looked at him, the guy was only four foot tall. But bought Honda's anyway, two of them, one for each foot.

1948 was the last year anything came decent out of Detroit, in 1949, the big three invented rust and continued that trend well into the late 80's, forty years of putting up with that crap. Energy and materials shortages, high gas prices, and junk to drive, but you had to get your kids to school and yourself to work. What a way to spend your life, and it's not even tax deductible. Who is running this country? Not the consumer.

bohica2xo on Tue October 02, 2007 10:37 AM User is offline

In 1986, I bought a new Ford ranger. It came with a single row aluminum radiator, with plastic end tanks. I was very skeptical, and figured I would cross the radiator bridge when it failed.

I could not have been more wrong. When the odometer turned for the third time - 300,000 miles in 2000, the original radiator was still doing it's job flawlessly. I gave the truck up @ 325k miles, and it was still leak free & cooling well.

I spent many years dealing with brass & solder radiators, and can tell you that the number one radiator killer is the "universal" hose with the big spring moulded into the hose. It places way too much stress on the hose nipples.

As for a finite life for a brass radiator - absolutely.
Brass is an alloy of Copper and Zinc, with various other traces sometimes added for specific mechanical properties. All of the stressed components in a radiator are cold worked to improve strength. The tanks are formed from sheet, the neck & nipples are cold worked from tube, etc. The cold working imparts added strength.

The down side to cold working brass is the eventual stress cracking. Industries that work copper alloys do a lot of annealing. Usually the final bit of cold working or "hit" is left as-is for strength. Eventually any place there is a stress riser, unpolished (sheared) edge or the like - it will develop a crack. Companies that manufacture things like cartridge brass take great care in annealing the neck area before shipping. It is not uncommon to see 40 year old cartridge cases crack all on their own. People who reload those cases anneal the cold worked area in the neck regularly for long life.

The filler neck crack is a classic example of a cold worked part that cracked from a stress point - with the help of the constant pressure of the radiator cap spring

The radiator in your car is subject to vibration input from the hoses, and a repeated cycle of hose movement evert time you accelerate as the engine twists in the mounts. Chassis vibration is input through the mounts as well. Eventually, cracks start to form in places like the tank where the nipple is soldered in or the nipple itself.

Sounds like you should just anneal all of the parts right? I have seen what happens when a radiator "repair" anneals the hose nipple completely - the nipple continues to collapse under the force of the hose clamp, and every time it leaks the clamp gets another turn on the screw...

Brass & solder radiators have a finite life. At some point, you will be chasing age cracks. A filler neck here, a nipple there. Next time it may be a tank.

I really don't care if it is "hecho en mexico" or not anymore. Your replacement core was probably "hecho" anyway. Bought a battery lately? Look close, probably "hecho" as well. All of our "dirty" industry went south of the border years ago. Perhaps if we buy enough of those "hecho" parts, the workers will stay down there working in their own country...

B.

-------------------------
"Among the many misdeeds of the British rule in India, history will look upon the act of depriving a whole nation of arms, as the blackest."
~ Mahatma Gandhi, Gandhi, An Autobiography, M. K. Gandhi, page 446.

iceman2555 on Tue October 02, 2007 11:03 AM User is offlineView users profile

The change to alum/plastic radiators was a big change for us in the 'rad' industry.....very skeptical to begin with....but they have shown their worth. Can not count the days spent working on a 'bench' repairing and recoring brass and copper rads. Always preferred the 'recore'd' unit to a replacement....more tubes and fins...but then the cost of new replacements knocked that market to the ground. Spoke with an 'old rad man' the other day....said he hardly ever does a repair anymore...just replace the darn thing.
Of course, in the first days of alum/plastic rads...repairs were a hoot...what worked...what did not...and did you know that at certain temperatures aluminum becomes invisible.....seen it happen...hold that torch a bit too close and the stuff simply disappears....lol.
Welding plastic....that was a real challenge...but over the years this too was mastered....or at least became a 'do able' repair.
Glad to be away from the business today....with all the EPA rules and regs....changes in materials....and not to mention all the lead floating around in the shop...wonder we are still vertical and breathing. Nothing started the day like running the header plate on a Cat D7 rad.....heat the header plate....spray with some muriatic acid...mmmmmmm....can still smell the aroma......great way to beat a cold.....heck...everything would run from those fumes....
The art of soldering a tank to a rad is becoming lost with all these crimped headers.....but what the heck...there is nothing so certain as change....and we have seen some vast changes is the A/C repair industry as well.
Ya'll have fun other there today....I sure am!!!!

-------------------------
The strongest reason for the people to retain the right to keep and bear arms is, as a last resort, to protect themselves against tyranny in government.
Thomas Jefferson

NickD on Tue October 02, 2007 11:13 AM User is offline

I thought the major problem with brass as each year, they were making them thinner and thinner, the brass radiator on my Ford tractor was sure built, was still in great shape when it was 50 years old when I sold it. The Honda's used a multi tabbed crimped on tank to the core with a neoprene seal, each tab was about a half inch long that could be easily be bent back to remove the tanks, thought that was going to be a problem with that neoprene seal, it wasn't.

Was a bit hard headed when spring clamps came out as opposed to the old screw type and changed them to the screw type with problems, now I am strictly spring type clamps, especially on plastic where the plastic can expand considerably. Maybe I didn't look hard enough, but seems like it is difficult to find replacement spring clamps, only see the stainless steel screw types. Ha, since I invested in a spring clamp pliers years ago, very easy to remove and replace, never leak or come loose.

JJM on Tue October 02, 2007 2:15 PM User is offline

Great minds think alike... I'm with Bohica on screwing around with a 30 year-old radiator. If you do successfully fix the leak in the area in question, within a short time others will spring up. It'll never end. And there's the issue of efficiency loss due to 30 years of crud buildup within the core. Sounds like it's time to sh_tcan the radiator. Maybe you can get a few dollars for scrap.

Like Ice, I too was skeptical of the plastic / aluminum rads, but it seems they're a big improvement. You can even replace the end tank seals if your inclined to deal with the crimps. But they've held up well, with none of the broken fill necks, drains, and nipples that I had originally feared.

Joe

NickD on Tue October 02, 2007 6:05 PM User is offline

One thing for sure, anti-freeze fumes are a severe risk to your health causing unrepairable damage. Even leaks under the hood whose fumes can work their way into the fresh air intake. Whatever the fix, please make sure it's done right, you are important to us.

iceman2555 on Tue October 02, 2007 6:07 PM User is offlineView users profile

A major problem with the alum/plastic units is operation with low coolant....steam pockets in the system will really play havoc with the plastic tanks. Need to get in the back my tool box..think I still have my 'plastic welder'....that was a learning experience....learned very quickly that plastic is not always the same as plastic....different types are as difficult to work with as different metals.....most common failure in the early units was the inlet hose connection on cross flow units....low coolant...steam from the inlet hose hitting this area...and lost of erosion...but then....that is what keeps us in business.....the cash flowing in.....

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The strongest reason for the people to retain the right to keep and bear arms is, as a last resort, to protect themselves against tyranny in government.
Thomas Jefferson

bohica2xo on Wed October 03, 2007 4:40 AM User is offline

Nick:

Thinner each year simply means that they need to work harden the material more each year to get the same yield strength from less material. As copper prices went up, more zinc went in as well... Your tractor's radiator was "red brass", and was most likely fully annealed when it left the factory.

Iceman:

Fix a plastic tank? If you never run the damn thing dry, it seems to last forever. My ranger spent several years on road salt in northern colorado, as well as a few years in las vegas. The first plastic/aluminum radiator I ever saw was in a VW Rabbit. They seemed to hold up well too.

B.

-------------------------
"Among the many misdeeds of the British rule in India, history will look upon the act of depriving a whole nation of arms, as the blackest."
~ Mahatma Gandhi, Gandhi, An Autobiography, M. K. Gandhi, page 446.

NickD on Wed October 03, 2007 9:25 AM User is offline

I repaired a cracked upper plastic nipple by taking a soldering iron and blending over the plastic and roughened it up, then used a super strong long drying epoxy with a thick coat around the base. Held very good. Reservoir was full on this GM thing, but a unclamped hose was letting air leak in instead of fluid so the radiator was half empty. Have to check the fluid level by removing the radiator cap and not just looking at the reservoir. But I wish someone will explain to me how to do that, if you no longer have a radiator cap.

iceman2555 on Wed October 03, 2007 10:28 AM User is offlineView users profile

When the alum/plastic hit the market....and yes, bohica VW was one of the first....Jap imports and some small domestics followed suit...it was necessary to repair many tank leaks..could not get new tanks at that time.....used a plastic welding tool to melt and form repairs...only problem..had to keep all the "polys' straight....dissimilar plastics are almost, if not, impossible to blend together. Started salvaging old tanks from sources....used material as a welding source.
Can remember when the VW alum/plastic came on the market...the drag race guys were going crazy for these things....light weight...a good heat transfer ratio.....ahhhhh...those were the days.....#.10 cokes.....moon pie for a dime.....R12 less than $.25/lb...yep...a quarter of a dollar......not sure what a Bud was....and not even sure they had Bud lite in that time.....but....hey...don't we have it soooo good today.....

Read today...with HD TV becoming the norm....stations are having to increase make up budgets for cast members...seems HD shows every flaw......damn...does that mean I can be pret....opps...handsome again....dark hair....abs......yeah...right......think that comes under the heading.....cloning....but the dilemma.....if cloned...do I get a new younger me...or simply a copy of what I see in the mirror each morning......if the latter...think I save the cash......spend in something worth while......had my eye on a 67 Vette 427 roadster, w/air.....hey..live in south fl...gotta have air......
Ya'll have fun out there today......

-------------------------
The strongest reason for the people to retain the right to keep and bear arms is, as a last resort, to protect themselves against tyranny in government.
Thomas Jefferson

NickD on Wed October 03, 2007 12:18 PM User is offline

How old are you anyway, Ice? Talking about the good old days, make sure you get an HDTV antenna to pick up those HDTV stations, but with all these new computerized low resolutions movies coming out, don't expect miracles. Actors will have to go on a diet also with these new 16:9 screen sizes, they all look fat stretching out the sides of the screen from many 4:3 ratio cameras.

The excitement we had in the 40's and 50's is all gone about the future, we had that excitement back then, today, everything looks negative with global warming, pollution, high energy prices, and major traffic jams. Also, no such things as collectors back then, how else could a kid working setting pins afford to buy a nice Cadillac limo or a beautiful practically brand new 1941 Buick? Well did go $150 bucks on that Buick because it was mint, removed the seat covers and enjoyed brand new upholstery in that thing. Model A's were plentiful, nobody wanted them and a really good car that ran and looked like new was ten bucks. I did pay an outrageous 50 bucks for a 33 Buick from a neighbor, but he had it since new with only 18,000 miles on it with new tires. I really liked these old large cars, but peer pressure was great and didn't know how to say, screw you back then, LOL. But those days along with gas wars are gone forever. Mom got on my butt for having six cars in the driveway. 400 bucks would buy a Piper Cub, 600 bucks would buy a really nice one and with aviation gas selling for 22 cents a gallon, no taxes, was cheaper to fly than to drive. So much for the good old days.

Only really good thing about today is having the internet so we can meet people from all over the world.

JJM on Wed October 03, 2007 6:01 PM User is offline

Quote
The excitement we had in the 40's and 50's is all gone about the future, we had that excitement back then, today, everything looks negative with global warming, pollution, high energy prices, and major traffic jams.

Nick that is perhaps one of the most profound thoughts I have ever heard. Thank you for so eloquently stating it. I believe that is what is wrong with our Nation today - that giddy optimism that was so uniquely American - where everything was possible - is now replaced by doom, gloom and dire pessimism. No wonder so many kids are so screwed up today, we've taken away their faith in the future and wonderful possibilities it can hold. And what has it all been replaced with? Fear, doubt, and self-loathing - hardly a recipe for the continued success of any nation.

Joe

chris142 on Fri October 05, 2007 9:17 PM User is offline

We rarely mess with the plastic/ Alum rads. If it's broke or leaking throw it away. Spend $120 to put a new tank on only to have the other side or the core start leaking next week. Customer is into it $240 for 2 new tanks plus labor when I could have sold them a new rad with a warranty for $206.75 out the door.

If it's a low milage rad and something nicked a tube my boss can weld it and they are happy. We had zero luck with that plastic stuff (stick-tite) you can melt with a torch to patch a hole in an Alum core. 3 days later it's back.

Most of our Copper and Brass recores are for 69-72 Chevy pickups and 48-57 Chevy cars. Copper has gone balistic here!

My out the door price for a HD 4R recore for the 69-72 truck with 16 fins per inch, Tubes 3/8's inch apart and 5/8 long tubes is $625!

mhamilton on Wed October 10, 2007 2:23 PM User is offlineView users profile

I really jinxed myself talking about my radiator... stopped at a store this afternoon, came out to find a river of green under my car. The core looks like it has a bunch of small leaks. I ordered a new radiator from CarQuest. I'll save the old one in case I want to have it recored. I was surprised when looking around online, now all the parts stores are offering an aluminum/plastic radiator for my application. Same shape, just the new materials.

NickD on Wed October 10, 2007 4:48 PM User is offline

Is that in thee Malibu? If it is, time to trade that thing off for a for-ty-for-for-d, if you can find one, they had pretty good radiators. Or maybe a fifty-for-fug, or is that bug? Dey ain't got no of dem radiators.

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