Well every manufacturer has a couple of things they could have done better here and there with all of their engines.

 

But anyway so i ordered a remaned head and i have everything back together and tonight i fired it up and its still blowing white smoke non stop. Which leads me to think it may be the block? I was half way through conducting another leak down test when a plastic thing-a-ma-jig on the passenger side that is hooked up to the heater hoses decided to break and so i figured that was a sign that i should call it a night. But i just don't get it. When i originally pulled the plugs there was only coolant on one plug and that was number six. Tonight after pulling the plugs again they were all dry, and a leak down test on number 6 appeared to pass. I think it may be time just to replace the engine with one that has about 150,000 miles less than mine.

 

I have to disagree with you. Plastic manifold shed a lot of weight, and conduct and hold less heat, allowing colder air to get to the engine, result, more power and less weight. The metal manifolds may not fail, but leaks int he gasket form just as often either way. I would rather have a plastic intake manifold.

Aluminum heads don't need steel inserts. Now I do agree that only having a couple threads engage the head is dumb (2V Triton). My Duratec has aluminum heads, and does not have problems with the threads stripping out, so did my Mazda B2600i. I have never run into a person that had the threads strip out on a 4.0L

The timing chain should never need to be replaced, so why does it need to be accessible? Compare to Honda and Toyota that still make cars with timing belts, which do have to be changed, and that are hard to get to.

The two part spark plugs were not designed by Ford, either Autolite or Champion came up with that one.

 

The two part plugs were specified by Ford engineers. Autolite and Champion are suppliers and build what the specs tell them to build so the plugs are designed by Ford.

IF you read on this forum or others the number of intake manifold leaks with plastic manifolds is much higher than metal. The vacuum leaks with metal manifolds are usually due to incorrect installation while the plastic design leaks when everything has been done correctly and that is a poor design. I would rather get power and weight improvements elsewhere instead of sacrificing reliability.

For a timing chain that should not need replaced there sure are a lot of these chains that are failing and need to be replaced. IMO

 

Is that really the whole story?

The metal ones with vacuum leaks are to to time and age and intake bolts that loosen over time. With the plastic ones, the same problem applies. The reason you currently see more problems with plastic ones is because the metal ones are the minority, most of them are very old and have already been either retired or the intake has already been redone.

Even if the two part plug design was a Ford idea, much of the problem is with implementation, not design.

As for timing chains failing, that is most often due to underlying lubrication problems with the chain and the chain tensioner. When the specified oil is used and changed at the recommended intervals, the problem is much less frequent. Many oils will meet the API standards in bearing lubrication, but valve parts, the rings, and the chain require friction modifiers, the quantities of which can vary greatly from brand to brand.

Even so, the Ford engineers never intended for the chain to fail, so why design it to be accessible?

Many of your comments here don't even really apply to the 4.0L. The spark plug problems are associated with the Triton motors. Furthermore, the tensioner problem really only applies to the SOHC engine, the OP has an OHV engine.

 

I agree that all engines have there own problems regardless of the manufacturer and no I do not hate Fords. My comments were directed at Ford because this is a Ford site. When on a Dodge site we talk about Dodge engines and there inherent problems.

Engineers have not cared a whit about accessibility for many many years no matter if the parts are known to fail or not. Even the parts that they say will need replacement (spark plugs for example) are not readily accessible for replacement. An engineers prime motivation is cost and ease of construction (cost again). Engineers live in a fantasy world where only factory parts are used and not in the real world where the end user uses what is available at a reasonable cost.

The fact that the problems I stated do not apply to all engines is obvious from my first statement when I did not state which engine I was talking about but gave a general "Ford engines". This does not negate the fact that these problems exist and in fact were design flaws. The fact that they were design flaws is obvious when they change the design to fix the problem. No one is perfect and everyone makes mistakes. This does not mean the problems can not be discussed or admitted to.

 

so i drove it around the block thinking, ok well hoping, that maybe that white smoke was just something residual and it would go away. We all know something like that just doesn't go away by itself. So after smoking out the neighbor hood with burning coolant, i got back to the house and i pulled the plugs, and i guess i didn't really run it long enough to get any of the plugs to look "wet" and a when i went to do a leak down test i didn't really see anything. Does anyone have any ideas? I've got duty tonight, but tomorrow after church i'm gonna work on it some more. Any ideas would be great.

 

I do agree, I wish that they would require the engineers to perform common repair procedures on the cars they design. And yes, everyone has the dumb things they do. I find in general, the Ford issues still don't seem as frequent or as severe as many of the issues I have seen with some other brands.

 

OK, so you replaced one head, and find nothing to indicated the OTHER head is a problem?

Usually, a minor head gasket leak is going to cause overheating as the combustion gases will be forced into the coolant. The coolant coming into the cylinder happens after shutdown, when combustion pressure is gone but coolant pressure remains. You'd see evidence of that on the plug methinks, and the steam wouldn't last that long while driving.

Any evidence of it sucking water elsewhere? Intake manifold--not sure of your design. Vacuum lines hooked up right? PCV not sucking oil?

FWIW, I would always pull both heads, but that's easy for me to say.

A cracked block might do this also.

Any contamination in the coolant or oil?

 

Look under the hood of any other manufacturer and you will find the same thing going on. None of em are built to last forever. None are built to be worked on. I own an '01 Explorer and love it. Right around 160,000 miles so far. We bought it used so I have no idea how it was maintaned. But Fords quality is better than most. Thats why thats all I drive............

 

I'm starting to lean towards the possibility of a cracked block because when i have the pistons at the top of the cylinder for the leak down test there are no bubbles in my coolant but with all the plugs removed its not to hard to push the piston down with the compressed air and then the valves open and the air escapes. Tomorrow i will put a back up wrench on the crank to keep it from turning and do the test again. And as for the intake leak, i don't think it could be that because each port is it's own machined surface seperated from the other ports. And the steam in my exhaust gets worst with more throttle applied.

 

Try piston down, valves closed and hold the pressure for a while. See if you get bubbles.

More throttle, more steam....

More throttle means more cylinder pressure, and less vacuum initially. As the engine "catches up", vacuum builds in the intake, including the intake port. A crack in that area might cause coolant to be sucked in.

Are there coolant passages in your manifold?

 

I thought the same thing about the possibility of an intake leak when i pulled the engine apart but the 4.0 OHV intake isn't the same as the old small block ford hea design and so the intake ports each have their own seperate surface so if there was an intake gasket leak you'd get water in your oil before you would get it in your intake port.

 

Alright, well let me tell you know i feel like an idiot. I can't believe but i'm glad it happened. So as i've told yall, i replaced the head and put everything back together. However when i started the engine it was still smoking an incredible amount, enough to make me skeptical. And it kept doing it for a couple days, however i would only drive it for like five minutes at a time. Well yesterday i started it up again and it was just running too smooth to have any mechanical problems anywhere, and it pulled 21 inches of vacuum with no fluctuation. And the smoking had gone away. So it must have been residual coolant in the exhaust, i just did not realize that so much coolant could build up in the exhaust causing it to still smoke. But the good news is that i fixed it several days ago, however i just didn't realize it yet.....Oops

 

Congrats on the fix. Good luck with it.