Ford experts need some advice here
 

Our family car (Lincoln Aviator 2003) just developed low compression in one of its cylinders. All the "experts" say it's done and it's going to be very costly to rebuild the motor.

My question is, if a motor swap is the some what cheaper option which motor/transmission should i go with?

Also if any vendor is equipped to do such a job please PM me!

i say trade it in and get a new explorer....save your self head ache.

It depends on what's wrong.. it could be just a gasket failure or something else.

The part it self is cheap, it is the labour that will cost you. Since the engine is mounted rather easily for access.. I would do a leak down test to figure out what's exactly wrong first.

IF you have the inkling or want to try to learn fixing a car.. this could be the chance. If it is just the gasket, you will remove one of the heads, send it off to be cleaned and planed etc.. replace gasket.. refill fluids.. etc

Else it is a 10 years old car.. time to ditch it.

what is the actual compression across all 8 ?

5.4L ? If so, did you blow a spark plug out of the threads ? VERY common ....

Retail value is probably somewhere between $8000-$12,000.

Trade-in value on a running, working average Aviator probably going to be $4000-$7000

If there is $4000 worth of work to fix the engine, then trade-in value might be $0-$3000.

Here is a link that details what is involved in doing an engine swap on an aviator.
Cooper Lake Automotive-Smyrna-Marietta-Kennesaw-GA-30082-770-431-1936 Lincoln Aviator Engine Replacement 770-431-1936

I can't comment on how many hours the job is, but lets say it's 10 hours (pbbly more like 13-14hrs) at $125 an hour, that's at least $1250 in labour just to pull and replace a motor, not including time to FIX the motor or the cost of replacement parts or replacement engine. Total cost will probably easily be $4000 to fix at a reputable shop.

The big question is WHICH cylinder was low on compression, and WHERE is the leak coming from? Plug, intake valve, exhaust valve, or piston ring?

If the leak is from a frontal cylinder and from a spark plug thread, you may be able to fix with the engine in place relatively easily / cheaply. If the leaky cylinder is near the back, or, if the leak is coming from a valve seat or cylinder ring - the engine most likely has to come out.

You will need to keep the same motor if you swap since the 4.6 and the 5.4 are not compatible...

Anybody know a place I can buy a used 4.6L Aviator motor?

Make sure you need a motor first! There are plenty of wreckers from Mitchell Island to Chillawack.

the 4.6L ford modular engine is pretty reliable.

are you sure its low compression?

its very common for spark plugs to blow out, and ignition coils to die.

because the aviator has the 4 valve version, it is more expensive, and harder to source.