A month ago I hit a deer in my 92 Accord.
Luckly the deer creased the hood and went over the top of the car.
I had the car looked at and there was no mechanical damage. However, yesterday morning right after my 52 mile commute I noticed a small leak before going into my office. I popped the hood and did not find the leak. Later that day driving a few miles I checked it again and when I open the hood I found the leak. It’s a hairline crack about 3 inches long across the top of the radiator. Any advice on repairing it so I can drive it the 52 miles home? Hank 92 Accord 4cyl

 

Itried to repair a similar crack w/ J&B Weld Epoxy. It seemed to hold for a short time and might provide a temporary repair. For a temporary patch following procedure is suggested.

1) Allow to cool completely and lower coolant level.
2) Buff an area around the crack extending 1/2" beyond crack in all directions w/ sandpaper to get a rough finish.
3) Mix J&B epoxy and "butter" over the crack and buffed border area.
4) Quickly butter a piece of rip-stop nylon (old umbrella material works fine) w/ epoxy to fit the buttered area and apply over the prepped site.
5) Apply a final layer of epoxy over the outside of the rip-stop nylon.
6) Allow to cure for at least 8 hrs (use heat lamp to accelerate cure).

No garuntees, but this may get you home. Bring along some extra coolant in case the patch fails. The high temperature of the coolant (180-190F) weakens the epoxy and also causes extensive thermal expansion/contraction during warmup and cooldown. Very tough to get a permanent patch to work under these conditions.

A new radiator is ultimate fix.

good luck

 

You could probably pick up some of that high temp epoxy from an auto parts store. My dad did that once as a temporary repair on one of our radiators when I was a kid.
The guys at auto parts stores are actually pretty knowledgeable when it comes to common things such as radiators. Go into one like Advance or AutoZone and explain the crack. they will be able to recommend things for at least a temporary repair. I am not sure how well radiator repair products work though. You may wind up needing to buy either a new one or a used one in good condition in the long run.

I see texashonda responded in a little more detail than I did as I was typing this post.

 

get a new radiator asap, but in the meantime you can get some quick-drying high temp epoxy as texas said and smear it over the crack. maybe try putting some sort of loose clamp on the rad to hold the crack shut totally? then epoxy?

make sure you carry around some extra coolant with you!

 

Don't waste your money on a new radiator. Repair it with JB WELD. I have done it before and it works very well. Just make sure you sand the area you will be applying it to and clean it off very well before applying. I would use some brake cleaner right after you sand it. That will get off all the little bits of debris off and remove all oil.

I have used this stuff on a motorcycle engine case that had to hold hot oil. No leaks, nothing. Great stuff. Try a $5.00 tube before you get a $300 radiator.

 

The top tank of the radiator is plastic, right?

Be aware that's a brittle-fracture material, so when the repair eventually fails, it may just fail suddenly & completely. The radiator is under pressure, so it's a little different than a crankcase.

JB Weld is good stuff, & everyone has suggested how to make the most of it. But I wouldn't wait TOO long before getting a new radiator.

 

Right. Give it a try and monitor it. You may be surprized.

 

First ..thanks
Second I could not find the JB Weld Epoxy (went to two stores) I was able to get Permatex Fuel tank and radiator repair kit. It is an epoxy stick that you mold to fit.
I cleaned and sanded the area and have just applied the epoxy.
I think it will take some time to cure, its 20 degrees outside.
Just in case I will continue to look for the JB Weld Epoxy.

Since you have been so helpful I have another question.
It looks like the top of the radiator is plastic and sits on the radiator core.
The top piece looks like it can be removed, is this true?
I'm trying not to replace my radiator completely.

Thanks again

 

If the crack is in fact in the top plastic of the radiator then chances are that weld stuff isn't going to work for very long... If the plastic is damaged you need a new radiator, if it's in the metal a repair shop can usually do a quick surface weld for like $5-$10 to fix it.

As far as I know the top piece can not be removed without damaging the radiator, it's fit and sealed on there so that it can withstand the pressures of the heated coolant...

 

You need a radiator, the one I just put on my '95 was $107 at Advance. You are not saving yourself any grief by trying to repair with ANY brand of epoxy. I've tried it before on another car and it failed, and if you google it you will find that there are few people who have done it successfully.

Most importantly, when it does fail, you will be 52 miles away from home; and it will probably happen this summer when you don't have the benefit of cold air blowing across the motor.

If your commute was 10 - 15 miles I would say it may be worth trying, but not 52 miles.