Small radiator leak?

steveu812 · 01-05-2009, 10:37 AM

I slightly drip coolant - only when warm. From below, it looks to be coming from the fan switch. I've snugged it a couple of times, but no go. Since the upper hose is just above the switch and could be dripping ON the switch and fooling me, I've snugged that up too. I've tried a pressure tester, but I also seem to have a leak it the upper most part of the reservoir tank, so air escapes there...

My next plan is to replace the fan switch gasket, but I figured while I have the radiator drained down, I'd add some stop leak when I refill it.

Comment?
Flames?
Brand/type recommendations?

Thanks

mallard ducks · 01-05-2009, 11:06 AM

Unless you've cracked the rad, the leak has to be coming from one of the hoses or the switch gasket/washer.

After replacing my rad, I had a similar leak. After much frustration using up gaskets/washers and wondering what was going on, I found the clamp for the hose above the switch needed more tightening down than I'd given it.

Needless to say I felt pretty stupid - things like this often turn out to be a lot simpler than you'd think.

Stop leak isn't a real fix for your problem and will do bad things to your cooling system. Tighten your hose clamps, even if you think they're tight enough, before you do anything else.

legoland951 · 01-05-2009, 11:31 AM

I agree with using stop leak as a last resort if you are not going to keep the car very long.

John_AZ · 01-05-2009, 11:47 AM

+^X3
If you look at the following picture, you should get the fan gasket and the small nipple gasket at the top. Do not overtighten either item or you will strip the threads. (If this happens, J-B Weld is your friend on the threads).

GL
John_AZ

krystar · 01-05-2009, 12:44 PM

try putting some gasket maker as u make the seal. or use teflon tape

KLR · 01-05-2009, 05:18 PM

I would agree with the above that you'll probably find an issue with the upper rad hose splitting, the hose clamp not being tight enough, or the gasket on the fan switch. If it does turn out to be the radiator, I wouldn't bother using any kind of stop leak product. It is not terribly likely to work for long (if at all) if the plastic end tank is cracking or pulling from the core. It is very likely to cause you other headaches. Just bite the bullet and replace the radiator (with used if need be) if it needs it.

steveu812 · 01-05-2009, 06:11 PM

Quote:

Originally Posted by John_AZ

+^X3
If you look at the following picture, you should get the fan gasket and the small nipple gasket at the top.

Hmmm...I'll recheck the nipple first as I'm not sure I ever have.

I suspect that +^X3 means that you concur with avoiding the stop leak, but what's it mean? Agree with the post above with 3x the emphasis?

Thanks

legoland951 · 01-05-2009, 06:22 PM

Just don't use stop leak. I would replace a radiator before using that stuff. I have seen cases where it clogged the cores of the radiator causing overheating and head failure/warped block.

John_AZ · 01-06-2009, 05:08 AM

Quote:

Originally Posted by steveu812

Hmmm...I'll recheck the nipple first as I'm not sure I ever have.

I suspect that +^X3 means that you concur with avoiding the stop leak, but what's it mean? Agree with the post above with 3x the emphasis?

Thanks

Yes

BTW the nipple gets brittle and cracks at the base of the threads.

(quote) "I've tried a pressure tester, but I also seem to have a leak it the upper most part of the reservoir tank, so air escapes there..." -Steve812

A new tank and cap will be an easy fix.

GL
John_AZ

HondaDustR · 01-06-2009, 06:15 PM

I've noticed the main coolant hose clamps (especially the large one on the water pump) need to be tightened pretty much as tight as you can get them before the clamp strips. I have no idea why the hoses on these cars need to be so tight to not leak, but mine have leaked every single time I don't tighten the clamps to within an inch of their life. Use good OEM style clamps, not the cheap ones you get at Autozone. The OEM style clamps can hold alot more tension before they strip. The clamps Pelican sells are good.

Check if the seal between the plastic end tank and the aluminum core is leaking at all. They tend to seep with age. I had successfully stopped mine from leaking there by gently clamping down the tabs that hold those parts together with some vise grips.

steveu812 · 01-23-2009, 04:37 AM

'Twas the top nipple it seems. I was able to snug it at least a half turn. No more wet spots!

EMBPilot · EMBPilot's Garage

take a look here, may also be helpful

coolant leak along side of radiator