I see that this is a common problem. My coolant started to disappear slowly
with no obvious puddles. I topped of the expansion tank in the AM and in the afternoon, I lost enough to start putting on the coolant idiot light.
Finally a found some antifreeze around the bottom of the radiator/ passenger side.
Any hints? I'm not used to slow SLOW leaks like this with the coolant system.

Should I consider stop leak if it is a slow leak with the radiator.
My sense is that Stop Leak products are snake oil.
what else to check out? Maybe tighten the clamps on the radiator hoses?
The leak is very slow.

I did a water pump last fall with the timing belt, but don't think that's the culprit.

Bill

Right side of the radiator is most common for the plastic to die. A stop leak product only works on metals, not plastic, so it won't work.

Check it after the engine has achieved operating temp and the thermostat open, that is when the pressure is the highest. I suspect you will be able to find the leak at that point.

Replacement is the only option.

Klaus
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Always willing to listen, just not able to take direction.

Tasca is in there cheaper than many of the aftermarket choices,
but who knows how much shipping. (How do they successfully ship a radiator.)

I see the radiator pricing and guarantees all over the place.
FCP says lifetime guarantee but the fine print covers only certified mechanics,
They leave the warranty up to your imagination if you're a DIY guy.
I looked at Autohaus (az) who has a lot of choices some more than OEM, and innerauto.com who has one for $120.99. What's your choice when you do a radiator.

Plus I see everyone wants $20 a set for the clips and o-rings
They must make up their profit there after pricing the radiator competitively.

How many of the brands need modification to fit right and how many drop in without a fight. Which are reliable/unreliable?

I know there's a lot of questions , but maybe you can help me avoid a landmine.

Bill

Nissens or OEM only, please. I always consider 'shipping' as an alternative to paying sales tax if I would get it locally. Yes, the O rings are expensive and you might get away with reusing the old stuff, but I would only get OEM spec. The others might be slightly 'off' because there is no quality control in the Far East.

Don't go cheap with the antifreeze either, Prestone G5 looks good as an alternative to dealer pricing, but always read the fine print.

Klaus
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Always willing to listen, just not able to take direction.

Thanks for the input. I love to get all I can before starting a job.
OEM or Nissens you say. Is Behr's OEM? That's what FCP is selling.
I see that Nissens is less money. Then comes the warranty?

The local Pep Boys and Advance are cheaper and have lifetime warranty.
FCP wants to add 10% for the lifetime warranty.

I'm glad to have such a small leak that I can shop around for the best performance and value.

And I do know about the "Almost" direct fit radiators. :-)


Bill

I just went through a similar problem with my car. It had a very, very slow leak for a couple of months. At least that gave me plenty of warning!

Behr or Nissens cost about twice what American radiators cost but I don't trust the cheap ones. Inevitably, they won't fit right or they leak. I've also read that some Nissens had issues (mainly from the RWD forum). I discovered that Valero is OEM on most 850's, but some had Behr. I got a better price on a Behr so I bought it. That about 3 months ago. Zero issues...

I went with a CSF when I replaced a while back and it lasted about 6 months before it became apparent that it wasn't going to work well. The channels weren't big enough to let enough flow through, so I was having problems getting enough coolant cooled and the engine was running hotter (~215-200) as well as spurting into the overflow when revving the engine.

When I replaced that (in March) I did the cheap thing and pulled one from a junkyard. Cost was $40 IIRC and I got an OEM that looked in good condition. So far, 8k into using it no leaks. Cleaned it out well before I put it on including flushing the coolant and ATF channels (I don't have a turbo, so no oil lines..).

If your junkyard guarantees it (even for 15-30 days) it comes out much nicer if you pick one with the same problem as you, you can swap it out. Bad thing is it takes about an hour or so to remove a radiator.

If/When you do the work, I found it much easier to get the radiator out by taking off the battery tray. You can grab extra clips for the tranny lines at the junkyard, I just reuse them unless they break apart. Use a hose clamp to hold them tight, the notches they have help hold the lines on. That said, I drove about 1k miles with the top line just shoved into it without any clamp and it didn't force itself loose.
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If you're not driving it "like its stolen," are you really driving?

When running, are the fins on that side a bit wet? It could be that the coolant has formed a hole in the plastic.
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If you're not driving it "like its stolen," are you really driving?