07 Mustang 4.0 SOHC into 99 Explorer 4.0 SOHC

[KelloggJ]

Hello folks, as the title says, I'm swapping a 4.0 out of an 07 Mustang into my 99 Explorer. I picked up the engine with 120xxx miles $350, nearest I can tell is the differences are fuel system, air intake, thermostat housing and a few other odds and ends. Nothing unexpected really.

My big question is this, the Explorer has an Oil Separator in the valley between the heads while the Mustang engine does not. There is a freeze plug where this would go, do I actually need to install the oil separator? It seems like Ford must have figured something out if they didn't include it on the Mustangs, right?

Also, the flywheels look the same and they both use the same starters with the same gear teeth, do I need to change them out?

I appreciate any and all feedback and advice, this ain't my first engine swap but, I'd rather ask folks with more experience with these engines.

Josh

 

[KelloggJ]

Well, I just tried removing the oil separator/crankcase vent and broke the damn thing... Looks like I'll be ordering a new one if it needs replaced, part number is F77Z-6A785-AB if anyone is interested in the future. Looks to be about $35 on Amazon and Ebay, I can't seem to locate it online on Rockauto or Autozone...

Josh

 

[Tech By Trade]

You should strip it to a long block and swap everything over from the other engine to be on the side of doubt. Save unknown problems in the long run.

 

[KelloggJ]

That's the plan, I've got the oil separator swapped out now. Just had to knock out the freeze plug and pop the new separator in.

Quick question though, I noticed that the Explorer and 07 Mustang use the same starter which means the same ring gear on the flywheel. They look the same to me and the spacing between the ring gear and the block is .02" different. Any reason my I shouldn't just use the Mustangs flywheel instead of messing with removing it?

If I do remove it, what's the socket size for this thing?

Thanks for the help,
Josh

 

[Tech By Trade]

Go to tasca and check the part numbers. If they are the same it should be the same part.