I'm contemplating removing the heads on my 4.6L 2 valve engine. Would that be a large undertaking for an old fart? I have overhauled many of engines in my younger days and thought it would be easier to replace the exhaust manifolds having them out. I understand there is much more replacement parts involved than the older engines. Bolts and the like that are one time use I'm told. I'd like to find a parts list of what is needed to do such a job.

 

If the intent is to remove the exhaust manifolds I would leave the heads alone unless it becomes necessary as a last resort. Removing the heads with the engine in the truck introduces thousands of opportunities for getting debris into the engine and cylinder bore.

As I am sure you are aware, exhaust manifold bolts/studs can sometimes be very, very difficult. Lots of info on the internet on how to remove stubborn exhaust manifold bolts/studs.

 

A 4.6 2v in a pick up truck should have tones of room to do the manifolds. I would remove the inner wheel well and then you'll have much needed access to the studs both top and bottom and the flange bolts to the cats..

Good luck and keep us posted..

 

My truck is a 4x4 with a big coil spring and shock in front of the manifold. The top of the brackets that these mounts to doesn't appear to have any space to get to the manifold. Am I missing something?

 

I too have the 4x4 with the shock tower right there.
it is a pain, but not impossible. I prefer to do as much as I can to elevate the cash outflow as we are paying almost $10 per gallon of regular unleaded gas.

Check out Brian's method.

 

Thank you Port11Gen. I'm with you on spending as little as I have to. I do not want to do the Head thing as I am not experienced with these new style engines. I have 2 new manifolds coming as the old one look like toast. So glad to see that it is doable with that big shock tower. UFFDA,$10 gas. That is nuts. Where are you located? It's $4 here in southern Minnesota.

 

No worries Ron. Yes, southern Ontario near Toronto. $2.10 per litre x 4.56 liters per imperial gallon.. yeah, they are killin us on fuel. Diesel is another 25 to 30 cents per liter.
it's very rude..

 

Though I've never had the heads off of a 4.6 in an F150 I have had the heads off a 4.6 in a Tbird. I think they have different intakes, but other than that they are basically the same. As has been said there is the possibility of debris getting in as soon as you pull the heads off, however if you're careful (and if you've overhauled numerous other engines, you've obviously got that figured out) you should be ok. The biggest issue with pulling heads on a 4.6 is the timing, as you're also going to be messing with 2 timing chains, gears, and cams. Careful marking of the chains and timing gears can help there. There is also the issue of the tensioner. It can be a little PIA to work with as well. I'm just trying to highlight a few of the things I remember dealing with when pulling my Tbirds heads, it's been too long for me to try and remember enough to do a tutorial. But there is a lot of info in various forums on the internet.

 

My concern is you still have the timing cover on, wont be pretty....
you mentioned the valve dropped, you would be able to see that by just looking at the valve spring from up above,

Unless you meant, the valve seat...

I agree with above, seems like way to much work without boroscoping it first.


ANOTHER huge issue I think you may have, im not certain but needs to be looked at.
The top retaining bolt for the timing chain guide may be attached to the front of the cylinder head..

Never seen on of these drop a valve seat before....

 

I don't think it would be a good idea to remove the heads to do exhaust manifolds.
That would be WAY, WAY more work.