Blown head gasket

[Willdallas2005]

Hey guys, my wife is on vacation at her mother's house. While driving she heard a loud pop and white smoke started pouring out. She stopped on the side of the road and called AAA. They took her truck (2007 ford explorer) to one of their recommended shops and they told her that the thermostat housing had busted and they had to replace that before they knew if any thing was wrong with it. She paid them, $530, to replace that and when it was done they called her and said it would be another 4800$ to put in a used engine. I asked her to ask why change the engine and they said it had a blown head gasket. I've never had a blown head gasket, but I've never heard of that being a replacement engine problem. So my question is, since I'm sure there are tons of people here who know far more about this than I do, is there anyway that sounds like what should be done?

 

[Joey Threesticks]

A blown head gasket can -usually- be repaired by a decent mechanic. The head gasket is simply a seal between your cylinder heads (the top of the engine) and the engine block.

Getting to it and replacing it can take several hours, so this is usually an expensive job. A typical head gasket replacement will also include replacing a timing belt (if you use a timing chain, you may only replace the tensioner assembly) and water pump replacement (may as well while you're in there) The added heat from this issue can also warp your cylinder heads. Again, this isn't the end of the world- I've had machine shops replane heads for me before and they've worked just as good as new. However, I know some shops that will not guarantee that type of repair.

The gasket does sometimes fail depending on a variety of circumstances, but I've never seen an engine that needed to be replaced entirely afterwards. I would get a second opinion from a mechanic
that you trust. If the engine has not been previously abused, and did not suffer too much damage from the initial overheating when the problem began, it should be salvageable.

Hope I've been Helpful, good luck to ya!

 

[Tech By Trade]

No one wants to pull a head on that engine. The 4.0l is a real pile of crap to work on. Depending on which side went, the engine has to come out anyway. Book time is 8 hrs to pull it. Not to mention the specialty tools required to time it come to another 300 dollars. And unless a shop has done it in the past there is no way I would trust them to do the job. A new used engine is probably the best choice. On a side note, how long was it pissing fluid out of the thermostat before she blew it up. Must have been quite a while without checking.

 

[Explorer_PL]

Joey -
You gave a nice overview of head gasket replacement on most of the engines - except 4.0 SOHC that is in Will wife's car. He did not mention what engine there is, but the thermostat housing is one of the "signatures" of the 4.0
That thing has 3 chains, one of them in the back of the motor.

Like Tech said, it's half the job to pull the whole motor out compared to do the head gasket and timing job on those motors.

Will -
that price has a little too much mark up. When I needed to replace a motor on mine (v8), 2 shops quoted me 20 man hours plus $ 2000 for a used motor.
Not sure what the hourly rate is by you, and search the salvage yards for a used motor with low miles.
Good luck

 

[Stick4503]

Problrm is shee is out of town. Rebuilding the top end of the engine will take days to weeks depending on machine shop time. Timing of this engine does take special tools that I have found most shops don't have. Plus it is easy for them to pull the engine and replace with another, quick turn around = quick cash. If you buy the OTC 6488 timing tool set (takes a week for delivery if its not on back order), head gaskets and head bolts, other miscellaneous gaskets plus machine shop fees you would be about $650.00 without any labor charges. If your timing chain guides are not shot ($300 plus for these) It's just quicker and easier for them.

 

[Explorer_PL]

Also, $ 530 for the thermostat housing ?
I do not like that shop
The housing is about $30 aftermarket or $ 50 Motorcraft.
How much time do you need to replace it, never done that before yet.

Can you tow the truck to your hometown and use your own mechanic ?

 

[michael loibl]

When I did the 4.0 thermostat housing on my 2006, it took me under an hour including new thermostat, new bypass hose, and checking every accessory pulley for slop and tightness while I had the belt off

 

[plasticseng]

Any shop that hit you for $530 to replace the thermostat housing on a 4.0 would be suspect in my mind. That is an easy one hour job.

I would recommend getting a second opinion.