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So it seems my '99 150 4wd threw a shoe last weekend. Bottom end let go in the 4.2. Anyone know what changed between the 99-04 and 05-08 engines? If I pick up a newer series engine (2005 or newer) what issues can I expect to run into when it comes to plugging in wiring harnesses and fuel rail stuff? Also, if there a difference between auto tranny cranks and manual tranny cranks? I know I will have to swap the flywheel. However, is the bolt pattern the same and are all cranks drilled for the pilot bearing? Lastly, what are the main differences between the Freestar 4.2's and the truck 4.2's? Could a Freestar be a donor?
I don't know the answer but I know I'd pull the blown engine (it's gotta come out anyway) and take digital pics of everything. I'd remove the all the harnesses, fuel rail, injectors, etc and give them the Ziplock bag treatment.
You then have both parts and photos to compare to potential donor engines. Let us know what you find out, as there are plenty of otherwise good trucks with dead 4.2s out there for the picking.
There are several differences over the years.
I think there have been 3 or 4 different intake configurations, including one that used a split intake runner setup with an Intake Manifold Runner Control.
Also, I believe early models used 2 different temp sensors which soon changed to a single temp sensor.
Early models used a manual throttle setup, later models used an electronic (servo) controled. I know my 2000 had the manual throttle (cable operated) and my 2005 has the electronic throttle.
Not sure about the crank. I'd guess - and it is just a guess - that all are the same.
I have no idea about the Freestar motor.
I'd try to find a 99 or close motor and avoid getting into a new (04/05 or newer) just because I'd not want to have to deal with all the differences and trying to make everythign work and work happy.
I'm sure it can be done, I'd just not want to hassle with it.
Thanks for the info guys. I thought about rebuilding this motor (and I still may someday) but it appears that a decent used transplant will be a fair amount cheaper than a rebuild (and certainly quicker to make happen). I quickly priced out parts and quit when I got to $1,000. That doesn't include machining. A reman motor is around $1,700-$2,000. Used engines of relatively low miles seem to be going for around $800 to $1,300 depending.. I agree it's a lot less headache to use a similar year engine, but low miles engines that are 10 years old are a bit rare. I found a '05 that has zero road miles. The scrapper bought it directly from Ford. It is a complete engine/tranny with all accessories on the engine. It was pulled out of a vehicle built on the line, but never driven. So, basically it's brand new, but priced the same as used engines and it came with a tranny I don't need that I can resell. As as the crank isn't an issue I am hoping I can swap parts between the engines to get everything to plug in. Worst case I may have to raid a bone yard for harnesses and such. Should prove interesting.
It shouldn't be too hard. The blocks should be the same so all you have to do is swap the old external stuff on the new engine. I'm doing a swap in my '97 right now and putting in an '01 4.2. I had to swap the engine harness, fuel injectors and water pump sensors. Everything is the same.
Hey Bob, My 97 4.2 finally hydrolocked last winter after setting for a couple of weeks awaiting fixing a starter problem. Did not know I had the leakage problem. Had 308K on it, so not complaining so much.
Anyway, I am finally getting around to pulling the engine out and intend to do a replacement motor.
I see that you used the 01 version. How difficult was it to find the right parts (junk yard?) and how much additional did the changeover cost because of the newer engine?
I have found 97s and 98s. The 98 I found is supposedly after the build date that had the updates to the gaskets so leaking, etc. not supposed to be a problem, but when I went to look at it, first thing I noticed was gobs of form-a-gasket around the timing chain cover...did not inspire confidence...
The yard guys said I could use the 99 and up that come with the electric acutators and swap out my lower intake manifold -- ugh. I like your solution better and was wondering how you made out and if it was relatively easy to do.