2004 Mustang Leaking Coolant

[dlundblad]

Good evening BITOG. Happy Wednesday.

My friend has a 2004 Mustang with the 4.6 that is leaking coolant. He says he has to top it off every other day.

I offered to potentially fix it this weekend, but wanted to see what I was up against first. I looked at it this afternoon and it looks to be leaking under the thermostat housing "tower" which is between traditional t stat housing and the intake manifold. The "tower" that I am talking about is the large threaded hole on the bottom right of the first photo that looks to be a cartridge oil filter housing. http://www.jegs.com/i/Dorman/326/615-175...CFQIxaQodT-ELkA

Assuming coolant is kept topped off, is this thing safe to drive without causing catastrophic damage? I checked the oil and saw no visual signs of coolant. (I realize that doesn't mean there isn't any though.) I am also not sure if that would cause oil and coolant to mix. My first experience with these was today by the way.

At first, I thought it would be just a gasket for the the tower, but nope.. looks to be the entire intake manifold gasket and a very lengthy process. Plus, if the whole thing has to come off, might as well do both. I am all about helping friends out, but this is something I feel I should not tackle on a car I do not own/ personally maintain.

Thoughts welcome folks.

 

[bdcardinal]

Yup intake manifold. Incredibly common on all 4.6 2V engines. Pretty easy repair also. Don't use the Dorman manifold, they do not retain the factory hardware and use proprietary gaskets between the intake and cylinder head.

The couple times I have done this job I replaced the spark plugs, coils, all hoses, belt, pretty much anything accessible while the intake is off.

 

[ShotGun429]

Use the Ford racing performance parts intake, its the same item as revised stock intake but about half the Ford dealer price, we sell alot of them here at the speed shop. good item, last one you will install on that car.

 

[Lyman]

Very common on these. I think every 4.6 that I have seen or worked on has had the intake replaced.

 

[aquariuscsm]

I hate how so many cars now have plastic plenums.

 

[kschachn]

Originally Posted By: aquariuscsm
I hate how so many cars now have plastic plenums.


Two of my cars do, I like them a lot better than metal (wet) ones. What's the issue? One less place for leaks.

 

[dlundblad]

So no issue with oil mixing with coolant then?

 

[artificialist]

Originally Posted By: aquariuscsm
I hate how so many cars now have plastic plenums.

It wouldn't be nearly as bad if the plastic plenums didn't have coolant passages in them. This is one reason why the GM LS-series engines are so successful. They don't have coolant passages in the plastic intake manifold.

 

[kschachn]

Originally Posted By: artificialist
Originally Posted By: aquariuscsm
I hate how so many cars now have plastic plenums.

It wouldn't be nearly as bad if the plastic plenums didn't have coolant passages in them. This is one reason why the GM LS-series engines are so successful. They don't have coolant passages in the plastic intake manifold.


I didn't know some plastic manifolds had coolant running through them, both of mine (ECHO and BMW) are dry. Why would they have coolant in them?

 

[bdcardinal]

Originally Posted By: kschachn
I didn't know some plastic manifolds had coolant running through them, both of mine (ECHO and BMW) are dry. Why would they have coolant in them?


It seemed like a good idea at the time? The early early 4.6 2V engines had an aluminum intake manifold so it wasn't an issue. There was actually a lawsuit and recall over the 4.6 2V intake manifolds. Warranty was extended to 7 years from in service date. The one on my 98 Mustang let go at the 7 year 4 month mark, no love whatsoever.

 

[artificialist]

Originally Posted By: kschachn
Originally Posted By: artificialist
Originally Posted By: aquariuscsm
I hate how so many cars now have plastic plenums.

It wouldn't be nearly as bad if the plastic plenums didn't have coolant passages in them. This is one reason why the GM LS-series engines are so successful. They don't have coolant passages in the plastic intake manifold.


I didn't know some plastic manifolds had coolant running through them, both of mine (ECHO and BMW) are dry. Why would they have coolant in them?


In V engines, coolant needs a way of being distributed into both banks of cylinders. The front 2 cylinders are an easy place to locate that coolant passage.

Since the BMW and Toyota Echo always had inline engines, there would be no need to distribute coolant across 2 cylinder banks.

 

[JustinH]

Funny, because they didn't go to the plastic manifold until 1996.

The earlier 4.6L vehicles had metal intakes.

 

[bdcardinal]

Originally Posted By: artificialist
Originally Posted By: kschachn
Originally Posted By: artificialist
Originally Posted By: aquariuscsm
I hate how so many cars now have plastic plenums.

It wouldn't be nearly as bad if the plastic plenums didn't have coolant passages in them. This is one reason why the GM LS-series engines are so successful. They don't have coolant passages in the plastic intake manifold.


I didn't know some plastic manifolds had coolant running through them, both of mine (ECHO and BMW) are dry. Why would they have coolant in them?


In V engines, coolant needs a way of being distributed into both banks of cylinders. The front 2 cylinders are an easy place to locate that coolant passage.

Since the BMW and Toyota Echo always had inline engines, there would be no need to distribute coolant across 2 cylinder banks.


A better design would have a dry intake with separate water passages.

 

[kschachn]

Originally Posted By: artificialist
In V engines, coolant needs a way of being distributed into both banks of cylinders. The front 2 cylinders are an easy place to locate that coolant passage.

Since the BMW and Toyota Echo always had inline engines, there would be no need to distribute coolant across 2 cylinder banks.


No, my BMW has a V8 and the intake is dry.

 

[artificialist]

Originally Posted By: kschachn
Originally Posted By: artificialist
In V engines, coolant needs a way of being distributed into both banks of cylinders. The front 2 cylinders are an easy place to locate that coolant passage.

Since the BMW and Toyota Echo always had inline engines, there would be no need to distribute coolant across 2 cylinder banks.


No, my BMW has a V8 and the intake is dry.


I didn't say that all V intakes are wet. What I said is that some intakes are wet, and I stated the reason.