Strange cooling issue...

[Orange75]

So, I had my 2003 Mach out for a rare nice weather day today. I made a stop, and when I came outside I noticed the ground was wet near the front of the car. I didn't see anything dripping from the car though, so I didn't think too much of it. Then as I was getting ready to pull into the gas station I noticed some steam out the front. I stopped and shut the car off and popped the hood. There was coolant coming out from around the radiator cap. I waited till it stopped, then drove home(Just 2 blocks away). It was doing the same thing when I got home. The strange thing about it is the temperature never went up at all over normal...not when driving or idling. The engine ran fine too...no change at all. Any ideas?

[bigtrain]

the overflow tank cap is probably bad same thing happened to me picked one up at advanced auto for $4 hasn't happened since or is it the crossover plug

[DSG2003Mach1]

what bigtrain said, try replacing the cap

[not a gt]

Originally Posted by DSG2003Mach1

what bigtrain said, try replacing the cap

I never noticed, does the big cap on the tank have a pressure rating like the old "spring"type??

[DSG2003Mach1]

Yes it does

[bigtrain]

16psi

[Orange75]

Thanks everyone! I was hoping it was something simple.

[bigtrain]

no prob happy to help

[Orange75]

Well, it looks like I may have a bigger issue. I went ahead and got a new cap. I also bought some coolant to replace what was lost, which was about a gallon and a quarter or so. Ran it for a while at idle and it got hot, though no fluid was pushing out around the cap this time. I read that these engines get air pockets easily, and that was definitely the case. Spent a long time working out the air pockets and got it full. Fired it up again and the temp came up to normal at idle. I took it for a spin and the temperature immediately began to climb. I went around the block and it was hot again, and once again the fluid was coming out around the cap. I'm not sure why it never got hot the first day I had this problem, but it seems something is still wrong. Next I'm going to change the thermostat to see if that fixes it, but I'm starting to worry I may have a head gasket issue. I've checked the oil and there isn't any fluid in it, but we'll see.

[bigtrain]

if you have air i the system you have to burp it from the crossover plug not the overflow tank the crossover plug is under the front of the shaker right side if you are looking from the front of the engine its it requires a 1/4" ratchet to open do you have any white smoke coming out the tail pipe it will smell like coolant

[Orange75]

I did not open g.crossover plug. I was already planning to do a full system flush before this happened, so I was trying to just get it filled back up and fixed for now. I do not have any white smoke. Nothing seems out of whack with the engine at all.

[not a gt]

I used this when I did mine

http://www.reischeperformance.com/refill.html

[Orange75]

Thanks. I'm going to go ahead and change the thermostat anyways since it's never been changed, so I'll just drain the whole system and refill it the correct way. Hopefully that takes care of the problem. I'd hate to have to open up such a fine running engine with only 63,000 miles on it.

[Lonestar77777]

You should be ok lets us know how it all turns out for you.

LS

[Orange75]

I sure will!

[Orange75]

It seems that all is well now. It turned out to be the thermostat. It's now changed, along with a new radiator cap and new coolant, filled through the crossover cap. I took a nice ride around town today and it looks like I'm back in business. Thanks again for all of your help!

[not a gt]

Glad you got it straight 75!

[bigtrain]

nice glad to hear you got it fixed

[sshakrr]

Hi All, Im in the process of draining my coolant and my crossover plug is very much stuck! I think the next step will be the vise grips on the plug cap. My local ford dealer cant find that cap on their parts list or diagram. Anybody have the part #??? Thanks. Ron

[sshakrr]

Well after 5 hours of letting Kroil penetrate the threads i was able to get it freed up with a vise grips. I found the part # F3LY-8A500-A.
Its fits 96 cobras thru 04 Mustangs and even some Lincoln 4.6L's too.
But the part has been discontinued for a few years now.?? Latemodel Restoration has them listed as # LRS-8500AA for $34.99. Was hoping to find one cheaper and do what the Lincoln boards suggested and have a nut welded on to it to make it easier to remove. For now its getting some anti-seize on the threads and back in it goes.

[sshakrr]

For those of you out there who are having a hard time getting the plug out, try this. I took a piece of 1/4" key stock about 12" long and put it in the vise with about an inch or so hanging out. I heated the stock up and bent a 90 degree angle on it. Let it cool and it works like a big allen wrench. Its always good to have a plan "B".