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Chevyguy
10-11-2016, 07:44 AM
I was driving My 04 Black on Saturday, went to pick up some friends to go apple picking. She said "your car smells hot" mind you it was 60 degrees outside and the car ran fine all summer with the AC etc... Yeah no problem...

3 min later waiting at Starbucks idling, my eye catches the temp gauge at 3/4 position!!! Yikes. So we headed home to swap out to the 04 Vic LX, the temp went down once moving.

When I got home later that afternoon, noticed no obvious coolant leaks, some crud along the COT plug I opened the COT plug and coolant came right out and a burp. Ran it for a while with the funnel in place, no real bubbles came out, and really did not add any net coolant. Drove around and of course could not budge the temp gauge past half.

Next AM, pulled the COT plug and put in the tiny amount which went down, tried to burp again and just filled the funnel up with expansion. This time I noticed the O ring on the COT plug was falling apart!! HMM

Turns out I must have had more of a air leak instead of a coolant leak, so it formed a bubble in the COT.

I tried to search for info and came up empty, then used google Site:www.mercurymarauder.net Crossover and found this


've been messing with these plugs since they were used on Continentals in the late 90's. There are two reasons why the plugs get stuck.

First, change the O-ring whenever you remove/install the plug. The coolant leeches up into the threads and corrodes them, making it impossible to loosen in the future. Now if that happens, #2 is to mix up a 50/50 mix of Acetone and Mercon V trans fluid. Use that as a penatrating oil around the edge of the plug. If you can see corrosion along the plug seam, you may have to do this a few times with a few hours wait in between.

Next, take 2 ball peen hammers (or a regular hammer I guess). Press the striking end of one of the hammers against the side of the sealing gap. The take the other hammer and tap the OPPOSITE side from the stationary hammer. Move each hammer around the circumference of the plug. Do this a few times. Then Tap on the top face of the plug a few times. You don't have to hit anything hard enough to cause dents in the metal, just some harmonic vibrations through the metal.

Then take the 1/4 drive breaker bar and loosen the plug. I have literally done 50 plus of these stuck plugs in MM's, Mark 8's and Continentals over the years.

Last, Clean the plug and the bore it goes in and change the o-ring! The size is 9/16" ID, 11/16" OD and 1/16" thickness. Use anti-seize on the threads only.

http://www.mercurymarauder.net/forums/showpost.php?p=1348163&postcount=9

So I am driving the LX till I get a new O ring from Mc Master Carr

The size has the -015 designation

Chemical-Resistant Viton® Fluoroelastomer—Offering the same excellent chemical resistance as multipurpose Viton® fluoroelastomer O-rings, except with a durometer of A90 (hard) for better wear resistance. These resist boric acid, citric acid, isopropyl alcohol, fuels, and transmission fluids. They meet ASTM D2000/SAE J200. Temp. range is -20° to 400° F. Color is black.
Chemical-Resistant Viton® Fluoroelastomer
Fractional
Size Actua Inch Size Pkg Qty. Pkg.
Width: 1/16 Fractional (0.070" Actual)
DashNo. ID OD ID OD
015 9/16 11/16 0.551" 0.691" 50

8297T125 $11.25
Product Detail
Abrasion-Resistant O-Ring, Chemical-Resistant Viton®, Dash Number 015

Packs of 50
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fastblackmerc
10-11-2016, 09:21 AM
How about a stainless steel plug with a new o-ring?

PM me if your interested.

lji372
10-11-2016, 12:02 PM
Or a stainless cot plug with a gods head engraved in it??

http://www.mercurymarauder.net/forums/showthread.php?t=92253

justbob
10-11-2016, 03:00 PM
Make sure your fan is working.


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Turbov6Bryan
10-11-2016, 08:52 PM
Take the cot plug to a hydraulic hose making shop

Tell em what it's for and they will get you the correct durometer o-ring

For like 24 pennies