I have a recently purchased 2003 F-150 with a 4.6 (Romeo based on the W in the VIN) that has a worsening oil leak from the rear of the RH head gasket. The truck is overall in very nice shape, 130K and mostly rust free, so it’s worth fixing. The engine itself works fine, no bad noises and doesn’t burn any oil; internally I mean, what’s leaking on to the exhaust is pretty awful. I’m going to pull the engine soon and I’m currently in the research phase of figuring out which way to go. I’m seeing three ways to proceed here, and I have a few questions.

1) Pull the engine, disassemble, send the heads out for resurfacing (maybe), then reassemble with new parts. Figuring in the head gasket set, head bolts, timing chains, tensioners, water pump, and probably the oil pump while I’m at it, parts come to about $600. I haven’t called any machine shops yet, so I’m not sure what that will run, but that leads to my question…
Is machining the heads necessary? It seems like it would add a lot of expense and time for an engine that wasn’t overheated.

2) Find a used 4.6 (I know I need to avoid the pre-PI) and either install as is, or do the above to it. The advantage there is I could keep using the truck while/if I redo the used engine.
I found someone local who’s parting an ’03 Explorer with a 4.6 and a bad trans that has only slightly more miles. From what I’ve read, these are aluminum block which would be cool, but they’re also Windsor engines. I know I’ll need the flexplate from the Explorer, but other than that are there any issues with going from Romeo to Windsor?

3) Finally, change over to a 5.4 2V. Again, either swap in as bought, or refresh. My question here is, other than getting the PCM re-tuned, are there any other potential problems here if I can find one of the same or close model year? I’ve read I need to use a torque converter from the 5.4 but other than that and the new tune, it sounds like a fairly 1:1 swap.

Thanks in advance for any help/tips/suggestions you can offer.

 

Leave it stock
Put a reman engine in it

 

A reman'd engine for a head gasket? Yeah, I guess ideally, but just picking one at random,...



That's more than I can swing at the moment. I have a contractor coming in a few weeks to put on a new roof. All my savings and then some is going towards that.
I had time to do some research on the whole Windsor vs. Romeo thing and it sounds like the differences are mostly internal. The only one that that will make a difference is the flexplate either having 6 or 8 bolts to attach it to the crank. At least that's what I was able to find.
I heard back from the guy with the 4.6 in the Explorer. He says it starts and runs, but obviously doesn't drive with the bad transmission. I'll probably go check that out. If it doesn't look worth it, it's easy enough to say no. I should have the weekend after this one free to start removing my engine. If I haven't come across a good used one by then, I'll go ahead with the rework on mine.

 

just leave the engine in the truck. Pull the head have it decked put a new top end gasket set on it

 

If you pull one head, jerk the other. Do a valve job, even a DIY one to relap then stem seals. My spare 5.4 PI heads (need for Expedition) leak like crazy from five of eight intake valves, unsure mileage but trans died in the truck so it was scrapped.

 

I would first make absolutely sure that the leak is from the head gasket and not somewhere else. Oil can travel down the seam between head and block and leak far from where it started.

Then if you're positive it's the head gasket, replace just the head gasket. The "while I'm here" stuff will add up and each operation has the potential for breakage and more money spent.

Could be a front cover leak, trailing back to the back of the head. A head gasket oil leak alone seems surprising. Why no coolant or compression leakage?

https://www.rockauto.com/en/moreinfo...choice=0-0-1-1

 

Thanks for the replies everyone.

From what I'm seeing, it's not an easy job to remove the cylinder heads on these trucks due to the engine being set so far back. That makes it especially difficult to set the head back on without damaging new new gasket. I've seen posts where some people lift the cab off the frame and slide it back a little to create clearance. I don't have a lift, so that's not an option for me. And I'm sure it's possible to do in the truck, but it really does seem like removing the engine is actually the easier way to go. But once I get into it, I can make a better determination.

Good tip on the valve guide seals, I think the Fel-Pro head gasket set does come with new ones.

I've always thought of leaking head gaskets as coolant and not oil too, but apparently it is a thing for these engines. I asked the search engine:

A couple of the actual results:

Servicing 4.6L And 5.4L Engines Found With Cylinder Head Oil Leak Or Weepage – UnderhoodService

Head leaking oil - 4.6 2v Windsor - Ford F150 Forum - Community of Ford Truck Fans


Finally, I got back there with the bore scope. The first picture is from the side of the head looking down (doesn't seem very wet up towards the valve cover). And the second picture is from the side of the block, just below the exhaust manifold, looking slightly upwards.

 

Nice research work. If it's a fairly common problem, common enough that there is a special Ford "service-only" gasket (does anyone know what service-only means?), it seems like the fix is close to guaranteed if you do it right. So you're down to the question of how to get it done and what else to do "while you're in there".

But, just to be thorough, you didn't do the black light test. Still a chance you could find out you removed the head for the wrong reason. Good luck either way.

"Once an oil leak is verified with a black light test at the head gasket joint"

 

What about the timing chain, would it not need re tightening?

 

Timing cover has to come off for head job, it is really easy actually.

 

Depending on the mileage there's potentially broken teeth on the chain to replace.

 

I wanted to give an update on this, as it's taken me until now to get the engine out. I'm just doing it an hour after work here, or maybe a few hours on a weekend, just as time is available. It's not crazy difficult, but it's defintley not easy either. I had to replace a 302 in an '85 F-150 I had many years ago. That was actually multi-port fuel injection (the F-150s got it 1 year before the Mustangs), but that was much more straight forward as I recall.
The big issue is the back third of the engine being under the cowl. My harbor freight "shop crane" that I've had since the late 90's wasn't usable for this job because it just didn't have enough reach. I briefly considered removing the bumper and grill to get it closer, but decided to go with a hoist in the ceiling.


Even removing the water pump and harmonic balancer off the front of the engine, and the radiator too, you only get about an inch of clearance on either end.


Lifting from directly overhead is downright sketchy but it was the only option I had


And finally getting mated to the stand. Btw, the tape on the front bumper is to protect the paint because for numerous items at the rear I had to step up and sit on the upper rad support with my feet in the engine bay. This one was definitely a first for me. I'll post some more when I get it torn down.

 

Good stuff, I plan to swap a fresh long block into my Expedition and steal its 5.4 for my Screw.

 

Hey everyone, I have an update. This has been a very slow process, just getting an hour here or an hour and a half there, but I'm just about done. The new head gaskets are installed.


I did the timing chains and tensioners while I had it apart.


I also cleaned up everything and changed out the oil pump too.


I found out you can use a garden sprayer to prime the pump. This one was like $10 from the big box store.


Here's the total cost for everything, which includes any shipping and sales tax, so actual total cost. And I went with Felpro and Melling for most the major items. And since you have to pull the transmission dipstick tube and loose fluid, I did the trans. service while I was at it.


A couple take aways/lessons learned... First, I found out later the studs on the torque converter can snag the flexplate when you're pulling the engine, and shift the converter slightly forward. If you don't reseat it fully back before re-installing the engine, you'll wind up removing the engine again so you can fully seat the converter on the splines because it will be sitting too far forward. I found that out the hard way.

Second, in the process of cleaning the parts, I removed the engine mounts and didn't put them back on before putting the engine back in. I didn't forget, but I figured it would be easier to line everything up without them in the way. I guess it helped with that, but it was a major PIA to get the mounts back in after the fact. I had to remove the oil filter adapter to slide the driver's side mount back in, which led to another problem. I apparently missed torquing the top bolt on the adapter when putting it back on, because now it's dripping coolant. So close to being able to start it, but I want to get that resolved.

 

One question for anyone who can help me here. On the reconnection of all the wiring and hoses, everything was pretty self-explanatory, but I have no idea where this ground braid goes.


I remember I removed it just before I pulled the engine, but I can't remember what it was connected to. I searched the service manual and didn't see and sort of ground circuit diagram. From a picture I took at the start of this project, I can see it tucks under the cowl and run over towards the driver's side, but I can't see it after that. Any help there would be appreciated. Hopefully I can't get this 100% complete soon.