Radiator Leak Fix

2002 Camry LE, 4 Cylinder. My radiator leaks 1-2 drops per second. I’m not exactly sure about the leak position, but it seems to be somewhere between the plastic tank and the metal radiator core, and it’s not likely the pipe, cap, or pipe connections. Please refer to the photos. I’m trying to find a fix which can last at least 3-5 years.


  1. Is it helpful to remove the metal cover above the radiator and check for the exact leak point before moving forward? It’s like the leak is somewhere underneath.
  2. Will radiator sealant work in my case, e.g. (https://www.amazon.com/Bars-Leaks-1194-Grey-Radiator/dp/B006GUMITE/ref=asc_df_B006GUMITE/?tag=hyprod-20&linkCode=df0&hvadid=241975700326&hvpos=&hvnetw=g&hvrand=212615481032980707&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9004323&hvtargid=pla-583831908858&psc=1)?
  3. If not, shall I replace the whole radiator or just the plastic tank and gasket?

The best thing to do is to properly pressure test the cooling system to verify the leak source…

If the rad is leaking then it needs to be replaced…


If you want it to last, replace the radiator and the hoses from the engine. Drop in a new thermostat as well.

Retighten the hoses after a couple of months.

Anything else won’t fix the leak either at all or only for 6 months or so.


A teaspoon of black pepper in the coolant will temporarily stop the leak, but the radiator requires replacement.


Stop leak used to work pretty well on copper core/copper tank radiators but not so much on aluminum/plastic. Radiators have become so cheap that nobody around me has been re-coring them.

Yes it is.

You’ll never rest unless you replace the radiator. It’s an entirely expectable repair in a car this old. I know, my 1999 Honda is on its 3rd radiator. Luckily I found a bottom leak last summer before it failed catastrophically.

1 Like

There is a rubber seal between the core and the tanks, and rubber eventually rots away and starts leaking. The rubber gasket can be replaced, but it is likely to be more expensive than just getting a replacement radiator. Lots of labor involved in replacing just one gasket, and the other is still 20 years old.


If original you’re lucky it lasted 20+ years.
Based on personal experience with my own and friend/family Japanese cars, ~15 years is when this happens.
It’s a rite of passage.
Japanese cars of yore are remarkably trouble free, until they aren’t.
Aftermarket replacement should easily last 5 years, but OEM is worth the extra cost and would last another 15+.

1 Like

My 30 years old Corolla radiator developed a leak around year 25. I considered a repair, but when I priced out replacement radiators the decision was very easy, replace, they’re very frugally priced. I paid around $90 for mine. Replacement very easy diy’er job on my car. Can’t speak to how difficult it would be on yours, but I’d be surprised if it took more than a couple of hours.

Did you have any overheating incidents in the past few years? If so, that could be the cause of the leak. If there’s been an overheating incident, good idea as part of job to ask shop to test the head gasket or at least look for bubble formation in coolant when briefly bumping idle speed.

Coolant draining will be required. If more than a year old, good opportunity to replace coolant with fresh. Replacing thermostat and radiator cap makes a lot of sense as well. Your cooling system at that point should be good to go.

Note: Make sure the radiator vendor knows your car’s configuration and how you use your car. For example automatic vs manual transmission might require different part. AC system characteristics as well. Likewise if you drive in very hot areas or tow anything.

Good Grief George . Don’t you think the parts seller would know enough to sell the correct radiator ? How a person uses the vehicle matters , really ?


Yeah I replaced a plastic tank once. It was $35 and the supplier gave it about a 50/50 chance of success. Gotta remove the radiator, bend the tabs to remove the tank, then bend them back again and hope no leaks. That was before new radiators were selling for $100. Now, just replace it unless you like to fix old stuff and can get the part. Yeah

1 Like

Radiator replacement remains one of the easiest/low risk DIY replacement options so it makes no sense to use pepper, eggs, oatmeal or Stop Leak which only postpone the inevitable. .

The radiators, hoses. clamps, theromostats, caps and fluid are all relatively inexpensive and UTube videos are easily available. Just take your time, be careful removing any ATF cooling systems, save the original hose clamps and you should be able to achieve a future 100,000 mile repair with just basic tools and your time and save your spending money on “Miracle In A Bottle”…

BTW, my first automotive repair many years ago was on a radiator repair on my 1962 Nova, which gave me the confidence to to research and posssibly make my own repairs for the next 50 years.but in addition, it also gave me a great respect for the Professional Mechanics “who really know how to do it”.

1 Like

Never have any overheating problem.

One more thing I forgot to mention is that these plastic reservoirs (tank) get brittle with age so repairing a 20 year old radiator is really not a desirable option.

Then its a pretty good chance that simply replacing your car’s radiator, thermostat, and radiator cap, fresh coolant, you’ll be good to go. Most any competent independent shop should be able to do this job for you. Manufactures switched at some point from copper to aluminum radiators, in part b/c the cooling/weight ratio is better for aluminum. Less expensive material cost as well. Aluminum’s downside seems to be the radiator’s lifespan is diminished compared to old days of copper.

Suggest to not defer this work b/c leak may become worse without your knowledge, and then you may well have an expensive-to-repair overheating incident.

In my opinion, George, reservoir, along with upper and lower radiators hoses at the same time as the radiator and T-stat.

No complaints, your idea is even better. However both of those radiator hoses on my 30 year old Corolla remain in good condition. Whatever materials Toyota used for the coolant hoses in those days appears to be quite bullet-proof. San Jose has a milder climate than most areas though. Corolla’s overflow tank is showing some signs of age.

If you want to go as cheap as possible then at the very least you will need to replace the rad, if you want to do a more professional job then replace the rad, rad cap, rad hoses and clamps, t-stat and gasket and coolant of course…
Places like Roppel Industries or 1-800 Radiator & A/C in Nashville sell rad kits that come with everything but the coolant in Kit form… I’m sure they have the same thing in your neck of the woods…

TECH TIP: if you have some old spark plugs laying around then when you remove the trans cooler line (if rubble hose) from the rad shove the tip of the spark plug in the hose to stop it from leaking… If it is metal lines then you can use a short rubber hose with something blocking one end and shove over the lines to stop from leaking… you can do that on the rad also… (IF the rad has an internal cooler lol)

Then there is Crusty’s aspirin trick, from the Puzzler Files.