Fixing a Cars Radiator





Introduction: Fixing a Cars Radiator

 Recently I got a crack in my radiator and found out its going to be $300 just to buy a new one, and thats If I installed it myself, it was going to be around $500-$600 to have someone do it for me, I looked into other ways and here's what I came up with. Total cost $16, time 15min. lasts forever.

Step 1: Materials

 I went to a local napa automotive store, and found a kit that is designed to fix cracks and holes in plastic parts on cars and containers. It's a fiberglass repair kit and only cost about $16. 

Step 2: Directions

 I followed the directions that came with the kit but there were a few things the directions said to do that didn't work as well as they claimed, I'll talk about what I found that happened or worked better in other parts as they come up.

The kit came with  a strip of fiberglass cloth,. sand paper, a metal tube 1 time use brush, and a 2 part epoxy.

Step 3: Other Tools

Some other tools you'll need is a few simple things.

1.Scissors for cutting the fiberglass cloth to correct shape.
2.some sort of tool to scrape off excess material during the cleaning process, I used a small pick, a screw driver would work just as well.
3.A drill and a drill bit, the drill and bit are used to ensure the crack doesn't spread, Ill explain all that in detail
4.  air filter mask, I used a simple painting mask, but any filter mask would be fine.

Step 4: Cut the Fiberglass

 Cutting the fiberglass is really easy. it is just like cutting normal fabric so normal scissors work fine.

Step 5: Preping the Area

Make sure you scrape all excess dirt, grease, or any other dirt off, and wipe clean with a cloth or a rag, don't use paper towels because the may leave traces of fibers behind. Then use the sand paper to sand anything off that is left behind, and in order to give the fiberglass a surface to stick to.

Step 6: Drilling the Holes

 Drill small holes at the end of each crack to ensure the crack doesn't spread any further, I followed the direction that came with the kit for these steps. It was fairly simple, I used a 1/8th in drill bit but depending on the size of the crack you can use whatever size you need, don't go too big, the hole just needs to stop the crack.  

After the holes are drilled make sure you sand the area around the holes again so the fiberglass sticks to the surface.

Step 7: Mixing the Epoxy

 The bag of the epoxy tells you to squeeze the black section at the bottom and break the center seal. I found that once the center seal is broken squeeze both ends and it opens the entire seal. Once the seal is broken the directions say to mix for 30 seconds then once you cut the corner you have 5 min to apply. The directions are wrong, once the 2 mixtures interact you have less than 5 min before it starts to harden.

once you cut the corner of the packet open, apply some using the supplied brush to the surface of the area on and around the crack. Then spread the fiberglass cloth over the cracked area and cover the cloth with the rest of the epoxy. 

After about a min the epoxy starts to heat up, it got to the point where I could barley hold it, it started feeling like it was going to burn my fingers.. Once it gets hot it started coming out of the packet even faster more like a liquid and then within 30 seconds started to harden coming out of the pack. so move quick. 

I'm sorry I don'y have pictures of me applying the epoxy, once it was mixed I have about 3 min to do it before it hardened.

Step 8: Done

once its done it said it hardens within about 20 min, I left it over night in case it wasn't ready. If you use it too soon and it leaks, it will be almost impossible to scrape off the previous fiberglass and do it over. you can lightly sand the surface if your worried about the looks. mine is on my radiator under the hood so I wasn't really worried about making it look good.



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its a simple epoxy and fiberglass patch, as it may be working now, the time it lasts will depend on how clean it was when you applied said patch. I hat to be the bearer of bad news, but this is FAR from permanent. But dont trust me, Im just a pipe fitter who has temporarily repaired pipe (glycol lines) with far superior products in the oil field industry... the glycol, with heat and pressure will eventually cause a leak again..

...That was really insightful contribution; thank you, Captain Obvious!

If there is just a crack on the plastic part of the radiator and no damage on the aluminum part,you can take tge radiator out and either replace the plastic tank or have a shop replace the plastic tank,its not hard to do and most shops,if you bring them the radiator, will fix it for probably less than 40-50 bucks.

I have been in the radiator repair business for 33+ years I own my own shop in southern California and I can tell you that won't work for a permanent repair. It may buy you some time a week or a month but it will not be permanent. I have seen hundreds of these attempted repairs with every glue you can imagine and nothing works.

Just to be fair, you might not know if a lot of the repairs have worked and held. Working in a radiator shop, I doubt that people bring their radiator to you after it has already been fixed and isn't having any additional problems. Not that I think that the glue is a good idea, just think you might only see one side of it.

go to pick a part.. On the holidays in everything is half price.. You can get a good one of your choice. About $20.00 dollars

Radiators aren't made the way they used to be -- plastic and aluminum instead of brass and copper. They simply aren't easy to fix -- "patch" is a more correct term, as the repairs are pretty much temporary. The hot coolant mix and lots of thermal expansion/contraction, plus the coolant is under pressure (15-20 psi, most common in US is 16 psi) just don't lead to permanent repairs. The good thing is radiators are relatively cheap now, usually under $300 US. That's a good chunk of change if you are on a budget, but much less than replacing an otherwise good car. If on a budget you'd be better off to go to a salvage yard and find a radiator that will fit. Get one from the newest model that will fit (if you're handy you may be able to adapt from a much newer model). Even then it's a crap shoot -- the "new" radiator may not last more than a few weeks ( most salvage yards have a 30 day exchange warranty, some you have to pay a few bucks more to get that) or a year anyway. There's a lot of work involved in replacing the radiator, more than I'd want to do for a patch that may not last. I'd risk a salvage yard radiator first.

I've found a fairly simple solution to successfully repair a cracked plastic radiator.

Sand the crack and clean the area put some epoxy putty over it make sure it's placed on and pushed in correctly leave no spots for the coolant or air to leak out of and the trick is after its dried enough so it's hard rub water over it.

I've found a fairly simple solution to successfully repair a cracked plastic radiator.

Sand the crack and clean the area put some epoxy putty over it make sure it's placed on and pushed in correctly leave no spots for the coolant or air to leak out of and the trick is after its dried enough so it's hard rub water over it.