@Extinct ill pull the plug tomorrow and start the diagnosis and let you know the results.

Truck has never used any coolant, that and having brand new head-gaskets and studs are the main reasons I did not suspect HG failure.

Hopefully it’s just a matter of replacing the bank one HG and evaluating the condition of the cylinder. We will see...

 

Reading into how the lower intake manifold was so loose, sounds like someone half assed the job to get rid of it. Never done a head gasket myself but seems pretty straight forward and you sound like you could handle it no problem. Only sympathy to give here man, I know how painful it is too fight something on one of these trucks for so long. Hopefully you have a conclusion here soon, albeit wish it was a little simpler.

 

Those are my suspicions as well @Old Bertha. HG job done right before I bought it. Could be as simple as improper torque on the cylinder heads. Hopefully the damage is not fatal and I can get her going with just a single HG.

From what I have read #3 cylinder is not a common failure point for a HG.

 

Now here's a question that has been asked 1,000 times before I am sure, but struggling to find a good answer:

If I need to replace the motor (after proper diagnosis obviously) and I go with a Turner, can I do a 4.6 Longblock with NO SAI and just swap the ECU with a non SAI truck? I'd love to not have SAI but not willing to tape over the CEL...

 

Fuel on the spark plug, and fuel coming out of the cylinder head after removing spark plug.

 

I pulled the #3 plug as seen above. It is coated in fuel. No coolant, just fuel.

The link below is to a video where I cranked the truck without the #3 plug. You can hear a grinding/ scratchy noise when it turns over and then blows a bunch of fuel out of the cylinder head.

Correct me if I am wrong, but what could cause that other than a stuck fuel injector.

 

Wow, that is a ton of fuel. Now we know why it hydrolocked. I would be surprised if the injector is still intact, especially since it failed while running. Pop the upper intake off and pull that injector, let's see it. I would recommend checking the compression on all cylinders. Turn it over by hand with all of the sparkplugs out, make sure it feels smooth with no hitches. The oil is obviously going to have to be changed.

As far as SAI, the heads and ECU are the only thing different. I guess you live in a non-inspection state. You can just cap the plugs on the heads if you don't want to pop for non-sai heads. Honestly I would buy a low mile 4.0 block from a breaker before I would pop for a Turner. Are you really going to put another 300k on the truck?

 

@Extinct ill report back with findings soon. A friend of mine reached out and said he had an almost identical issue with one of his cars. It didn’t destroy the motor in his case, so here’s to hoping it’s salvageable.

No doubt it hydrolocked. Very interested to find the culprit.

With that amount of fuel it might be that the injector is broken. I’ve reached out to the injector company to see if there is any recourse as they promote a warranty.

When you say “breaker” I assume that means a 4.0 motor from a junkyard or something?

 

By breaker I mean the guys here and on facebook that specialize in Rover part outs. There are a few near me in VA and NC, probably some down in GA and AL near you too. The 4.0 engine is much more reliable, not a significant power difference.

 

I will certainly look into it. It seems clear that 4.0 motors are less likely to crack blocks, but from what I have read they all can have the same issues.

I actually found a truck with an AB top hat 4.6 for sale for cheap. The frame has some bad rust, but the motor has 20k miles on it and all documentation from the build.

I don’t have space for a non running parts truck currently, but for the price of the truck it would be a good option. The only downside is the extra effort to pull the motor from the parts truck.

What are your thoughts on P38 4.6 motors vs 4.0 motors?

I watched an interested video from RPI Engineering in the UK last night that suggested LR hand picked the better machines blocks for P38 4.6’s. Here’s the video: