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Blown Head Gasket

This is about a Ford Expedition 2000, 5.4 engine. I noticed burned coolant smell, which was traced to the right engine, right above the engine mount. I suspect a blown head gasket. This vehicle has had perfect maintenance at factory recommended intervals. It is now close to 260K miles of superb service. Since the coolant lose is still very small (about an inch down in coolant every two weeks), I intend to do nothing and let it run its course. What symptoms should I be aware of before i decide to either repair or change to a used low-mileage “new” engine. Am i doing the right thing here?

First you may not have a blown head gasket, maybe just a leak from a fitting or hose or something worse like a cracked block. The best way is to run a compression check of all cylinders and if it is blown you will find out where. If you are leaking coolant into the oil pay and lube system you will destroy the motor, so check out where the coolant is going…

Thanks for your suggestions. I checked all adjacent coolant hoses to determine that the leak didn’t originate there. Upon visual inspection, the leak runs out from somewhere behind the exhaust manifold, down to the engine support. Positively, there is no trace of emulsified coolant in the oil. Is that what I should be looking for as a sign that the engine is near the end of its useful life? I am more inclined to change the engine, even for a low-mileage used one, as i think it will only a matter of time for other engine components to fail. Is thsi a correct assumption?

Are you sure that it is not coming from the intake manifold coolant crossover? Head gasket failure is unusual in Ford Modular motors, but you do have a lot of miles. You may be on the right track thinking about replacement with a salvaged engine rather than fix a head as that would be cheaper with a 4.6 l. I don’ t know if the 5.4 is as plentiful. You could go to a Ford parts counter and see if you can get some of the stop-leak that they use from the factory. If you are very lucky, it might work.

http://www.fcsdchemicalsandlubricants.com/dealer/product.asp?product=Cooling%20System%20Stop%20Leak%20Pellets&category=A/C%20and%20Engine%20Cooling%20Products

May I suggest that you get a mechanics mirror and attempt to look behind the exhaust manifold. The problem could be a freeze plug that is leaking.

Thank you all for your suggestions. I’ll have a mechanic shop run a pressure test to rule out a blown head gasket. If pressure checks OK, I’d assume is a core plug leak, which I am sure wouldn’t be that expensive to repair. As far as i have researched, fix-in-a-bottle solutions are reported inadequate, most of the time. And when they work, the leak problem surfaces again soon after. I have to publicly recognize in this forum that this has been a very good vehicle to me. In part, I think, due to keeping up with the maintenance schedule, but on the other, with a few exceptions, we, that is Ford, still know a few things about making cars, and also with a few exceptions, there are great mechanics out there who know their field. That’s good old American ingenuity.

although GM is the mfgr. that had lots of coolant leak problems with intake manifolds they made of plastic, Ford is not immune. worth looking at this.

The expansion/freeze/core plug is a good suggestion. Sometimes they can be hard to get to making a simple fix expensive.

Well, upon inspecting closely, I found that the leak is coming from a point above the core plugs, most likely the joint between the iron engine block and the aluminum head, or in other words, I think it is a blown head gasket. The coolant lose is about an inch in the degas bottle per every 600 miles. I could try a leak sealant. Does anybody know what brand would be my best shot? I have little hope on this solution, but I can take a shot at it.

Ford put their VC-6 stop leak pellets in it at the factory. They are probably not cheap at since I think that they have to come from a dealer, but they probably can’t hurt anything:

http://www.fcsdchemicalsandlubricants.com/dealer/product.asp?product=Cooling%20System%20Stop%20Leak%20Pellets&category=A/C%20and%20Engine%20Cooling%20Products

Thanks. I’ll try it and let you know.