I noticed a small amount of radiator fluid on the fan shroud today. In addition, there's some caked-on radiator fluid along the top edges of the radiator.

The overflow container is filled to the line, and I didn't notice any fluid on the garage floor.

What's the next step? Should I put stop-leak in the radiator?

If a new radiator is needed, how much does the whole job cost? I presume it's best to go with a new unit vs. a re-manufactured unit, and if possible a Denso unit, which is the original in the car now.

Thanks,

Robert

 

I don't like stop-leak because it can gum up everything especially the small passages in the FITV & IACV.

Your leak might be as simple as the radiator cap. Under the cap there's 3 different rubber seals & the outermost one seals against the top lip of the radiator neck. Look for solidified crud around there, and especially look for nicks & scratches in the lip of the radiator neck. Hardened rubber seals and/or weak springs in the cap can cause leaks at the cap. If there's any sign of cracks in the plastic tank of the radiator, I wouldn't trust any kind of repair.

Worst case, it's leaking where the upper tank is crimped onto the radiator core, needing a new radiator. I don't know of "remanufactured" radiators; do they exist?

What kind of DIY work have you done before? If you're thinking of replacing the radiator yourself, let us know - it's reasonable for a backyard mechanic to do that.

 

You can get a radiator pressure tester as a loaner tool from a parts store. The radiator should hold about 16 psi without dropping pressure. The cap should hold pressure till 16 psi, the allow the pressure to release.

If you have to replace the radiator, the Honda radiator is expensive. You can purchase a Denso radiator for around $100. Replacement is simple. The only trouble you may have is removing the transmission cooling lines, if you have an automatic transmission. If you plan to replace yourself, we can give you the information needed and direct you to video on how to do this.

 

This type of DIY work is out of my comfort zone. I'm going to start with the easy thing - replacing the radiator cap. The green liquid is accumulating on the fan shroud, so the leak could indeed be coming from the cap.

Do I need to get the cap from Honda, or is a replacement part OK?

Is there any easy way to determine if the leak is coming from where the upper tank is crimped onto the radiator core? I did find some "baked-on" anti-freeze there.

BTW, I figured re-manufactured radiators were available, since so many parts come that way.

Thanks,

Rob

 

If I need to replace the radiator, I'll have a shop do the work.

The original radiator was made for Honda by Denso, so I'm figuring the $100 Denso replacement would be OK. Am I correct here?

Thanks,

Robert

 

When you get a new cap, you'll have new rubber seals. But remember to check real good around the neck where the cap installs. Particularly 2 places...

1- The top/outer rim. Look for that rim to be clean & free from scratches or gouges. That rim seals against the outermost rubber gasket inside the cap.

2- Just inside the rim, there's another "step" with a smaller rim. That's down a few mm inside the neck. That rim has to seal against the rubber gasket that's on a spring-loaded plunger in the cap. Again, look for scratches & gouges.

While you're looking, pay attention all around the neck, looking for cracks beginning to form anywhere in the plastic material. If you find any cracks, the radiator needs to be replaced.

Then, get it all cleaned up & dry. Look at it a lot when you first start it & warm it up. Once it gets hot & pressurized, you want to find the leak before it has a chance to drip all over. You need to pinpoint the location of the leak, not just where the liquid eventually collects.