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I am checking my trans fluid and happen to look over and notice a thick brown goo forming in the intake bolt well on #1 cylinder. It is really thick. I think,,, oil??? Then I look at the hose connection to the thermo housing and it looks like it's dripping from there and running down into the well of the intake bolt.
I was in such a hurry to find the source that I wiped it up before thinking to take a picture. It took the pic and you can see where it was and the color.
I hope it's just a loose connection and the coolant turns brown and thick from boiling on the hot intake.
Has anyone seen this before?
Looks like just a bad connection between the radiator hose and the thermostat housing.
This is probably happening after you shut down the engine and the pressure in the cooling system increases.
In your photograph, it looks like you have a chrome plated thermostat housing.
Those are notorious for leaks.
Replace the housing and it should take care of the leak.
It is common for the coolant to turn brown when it pools on the intake.
There are a lot of contaminants floating around in the engine bay.
Pop your radiator cap and inspect the color of the coolant in the radiator.
If it is clean you are ok.
If it is rusty brown it's time to flush and replace it.
You can continue using a chrome waterneck. You just have to know how to tweak it. Place the waterneck on a belt sander to remove high spots and rough-up the chrome. This will give you a good seal. Then, instead of using a $2 paper / fiber gasket, splurge on a Mr. Gasket silicone unit, around $26.
<<<<<<< see? Chrome waterneck on mine, never leaks.
Last edited by HeadsU.P.; Aug 27, 2020 at 04:12 PM.
The base of the housing is dry. It looks like the leak has been from the hose connection to the snout. I'll try pushing the hose farther onto the snout and re-tightening.
The base of the housing is dry. It looks like the leak has been from the hose connection to the snout. I'll try pushing the hose farther onto the snout and re-tightening.
This is not the fix.
The chrome finish is too smooth and when the chrome is applied it can leave an uneven surface.
The best fix is to do as suggested by HeadsU.P. or to replace the housing with a non-chrome unit.
The housing to intake area is also a common place for these to leak and so far you've been lucky.
Last edited by OldCarBum; Aug 27, 2020 at 04:25 PM.
No offense but, you have a nice Intake there. Then you cheaped -out on hardware. Looks like corner store, maybe grade 5 hardware bolts and washers. The washer on the right is almost gouging the aluminum. Note how the top of the bolt head begins to round-over. Those are the fasteners that a socket or wrench will slip off of.
For around $27 you can get ARP Intake Bolt Kit in black oxide or chrome. Has built in washer, and has a 12 point smaller head which makes torqueing a breeze.
Back to your issue. That color looks like a petroleum stain. You have a dripping fuel line nearby?
Hmmm, I'm not too worried about the bolts. We originally had the Edelbrock bolts for that intake, but there was some issue, so the builder used those.
As far as the dripping fuel? There is no fuel anywhere near that point on the intake. The fuel line is on the other side of the intake and it is braided line through AN fittings. There is no leak trail from the carb. If you look, you can see the drip point directly under the top hose clamp onto the intake and then trail down into the well. I tightened the clamps and drove it for a while and it appears to have stopped. The clamps were somewhat loose. I'm pretty sure that the stuff was cooked coolant. That intake is very hot and the stuff was sticky, as I would expect from glycol???
Thank you for your response.
I had a stubborn waterneck that refused to seal at the Rad hose. I ended up smearing some Permatex clear RTV here & there while twisting the hose on. Clamped. Let sit overnite. Fixed.
Last edited by HeadsU.P.; Aug 27, 2020 at 07:17 PM.
From: SUFFIELD CT USA 2023 C8 CORVETTE UN-MODIFIED FINALIST
2023 C8 of the Year Finalist - Unmodified
I would make sure the screw on your clamp is tight first. If it then replace the Chrome or rough it up or prematex as suggested above. how many miles on that housing!
Last edited by BPHORSEGUY; Aug 27, 2020 at 07:30 PM.
Coolant Boil on Intake???
