I'm needing to replace my '98 4.6L 2V SOHC romeo (cast F7AE) in my F-250. The block is cracked and one of the heads is pretty well shot. Everything else is still fine. The possible replacement 4.6L romeo I'm looking at is from an '06 F-150.

I've noticed that starting around '05 they start referring to these 4.6L engines as being the "new style". I'm familiar with the mods to the heads around '01 (PI instead of NPI), but what the heck does "new style" mean? There was also something they called "heritage" in '04?

I use this as a reference, but it doesn't mention that: http://www.therangerstation.com/Maga...0/Ford_4-6.htm

Is there anything I should be concerned about with dropping this engine in?

Thanks,
Steve
Kissimmee, FL

 

posted before I found this https://www.f150online.com/forums/v8...new-style.html

its apparently just a body styling issue, but it seems I may have some issues with the PCM ... anybody got some leads on how to deal with that?

 

Can't I just use my old PCM and wiring harness from my '98 on the '06? Are the connectors all the same?

 

There may be some differences in location and function of some sensors. You will need to use the 06 intake and exhaust manifolds as it's a PI engine, the 98 isn't. You will have to use the 98 throttle body as the 06 is electronic, no cable, not sure how it fits on the 06 intake. Not sure about the EGR system, I think the 06 has an integrated assembly with no separate DPFE. The 06 fuel rail doesn't have a test port or a FPR. Overall, it shouldn't be too difficult a swap.

 

Use the PI 06 intake manifold and exhaust as glc said. Then use the 98 throttle body along with the 98 throttle body adapter on the 06 intake. You can then reattach all vac lines and DPFE and EGR in their 98 location. Also use the 98 engine wire harness along with the 98 coil packs/sparkplug wires and 98 fuel rail. You can also use the 98 PCM/ECM as the engine should run fine with it. However a tune can be performed if desired but some run very well stock using a PI engine. Oil pan might have to be changed depending where the drain plug is, should be ok coming from another truck. Pretty straight forward swap.

 

Thanks for the replies. I've been offline and out of commission for the last few days with a bad cold.

The guy who had the engine was presenting himself as a private seller on CL. When I finally talked to him he turned out to be with a salvage yard ... AND wanted a $250 core charge, and wouldn't take my bad block and heads as return for the charge. The total, after tax, would have been almost $1400. So ... heck with him.

I ended up renting a truck from Enterprise for $70 and going a couple hours away to pick up a '99 Grand Marquis engine for $475 from a scrap yard. They gave me a 30 day warranty on it running and claimed it ran great before pulling it. I already have it on my 1 ton Harbor Freight engine stand and am diving into it.

Observations thus far:
1) I will certainly need to use my old intake manifold, throttle body, plenum, and fuel rail (expected)
2) I will use my old PCM and wiring harness
3) the EGR tube is on the opposite side, so I will use my old exhaust manifold, if I can restore it, otherwise pick up new ones
4) it seems that the PCV valve connection into the plastic valve cover broke off, so I will use my old valve covers too
5) I can turn the crankshaft comfortably (good sign)
6) all but one spark plug look like they are getting clean burns

I picked up a leak down compression tester from Harbor Freight. So, before I tear it apart any more, I'm gonna get some compression baselines on each cylinder before the rebuild.

Other than cleaning everything up and doing a nice paint job, the current plan is to:

* replace the piston rings and hone the cylinders
* replace the crankshaft seals
* clean out the head ports
* clean and relap the valves
* clean out the fuel injectors
* put in new valve seals
* new gaskets (head, manifold, exhaust)

I'm torn on whether or not to replace the springs. A broken spring is what caused my engine to fail in the first place.

Any recommendations for things that really ought to be done for a guy doing a rebuild on a budget?

Thanks,
Steve

 

Since both engines are non PI then the truck intakes manifold can be used. The Mustang went to PI in 99 and the Crown Vic went to PI in 2001 so make sure it is in fact a Crown Vic and not a 99 Mustang PI engine as the intake manifolds between non PI and PI are not interchangable. Also your engine is a Romeo code (W) and you will need to confirm that the Crown Vic is a Romeo as well if you are going to swap the cam covers Windsor and Romeo cam covers are not interchangable. The Crown Vic engine should be Romeo as almost all car 4.6s were built in Romeo. Buying a pulled engine you never really know if it was an original engine or what style of car it really came from...lol. If you get good leakdown and compression I see no reason to change rings and work on the bores but its up to you. Same with valve work. Changing valve seals and crank seals is a good idea I would also buy a new set of timing chain tensioners and install them as well. Check the valve train out of course and especially on the one cyl that shows a dirty sparkplug.
Check Rockauto.com for parts they are good to work with and the prices and selection is better than most in my opinion. Also be careful during the disassembly and reassembly as this engine is not freewheeling and with the chains off the valves will hit the pistons and they bend easily.

 

Thanks Dynotech. Yeah, they are both Romeo. So, the cam covers should be compatible. They look the same. I guess I'll decide on the piston rings when I see the leak-down results. The timing chain tensioners is a great idea ... thanks for that.

 

... and OMG! I just checked http://www.rockauto.com/ I love this place! Amazing prices. Thanks for the tip.