[B]2001 F250 Super Duty, 5.4L V8. I have replaced the line that runs from behind the water pump to the heater core. I thought I had gotten the leak, but it seems to be back now and as bad as ever. The coolant still leaks down where the older pictures show,
but the coolant actually seems to start under the alternator and behind the water pump. I think the fan and wind form driving is blowing it back that direction. I am adding a photo and wonder if on the bottom side of the cross piece that the thermostat housing on the drivers side and the heater core line on the passenger side connect to. I am really at my wits end with finding this leak. Has anybody found an odd leak like this that can help me out?




Passenger Side



Passenger side.

This is the passenger side under the truck and it appears to be running down over the top of the front of the transmission, burning on the exhaust pipe and running down part of a suspension rod as seen in the photo.

To be honest I cannot see up far enough to see a source and I cannot see anything from the top. I can see it drip a little when parked and running, but assume driving it is causing to to run harder. What you see is only from driving it about 10 blocks and back to the house after letting it warm up for about 20 minutes after the fuel filter replacement.

It almost smells like antifreeze but it has a little more oily consistency. I doubt Antifreeze because it seems a bit far back and the consistency almost seems like tranny fluid even though it doesn't really appear red enough to me. IDK. It smokes white when it is burning on the exhaust so I feel like it is spraying from a leaking line someplace perhaps?

I sure hope someone has some experience and ideas. It may have to wait for a proper diagnosis as I cannot spend too much time out in the ice and snow trying to figure this one out.

Thanks again for any help.

 

That would be a safe bet your coolant crossover is leaking which is where the rear of your alternator mounts. It usually leaks where the aluminum meets the plastic intake. Only good fix is replacing the intake manifold. I had this happen to my last truck.

 

Okay. Thank you. I was afraid of that. I really do not want to tackle the intake manifold. I think I may just buy the parts and have someone do it for me. It is about the only place I can figure the coolant is coming form now.

 

It isnt fun or cheap. I recommend using the Ford intake manifold. Learned the hard way on that one.

 

All fixed and final update so anyone else having this issue with an unknown coolant leak can check this as a final resort. I say final because it requires the removal of the intake manifold. The leak was resolved and was the coolant crossover attached to the front of the intake manifold.

I bought a replacement manifold with the coolant crossover attached, ($152.00). Once it arrived I pulled it out of the box and inspected it. I decided that there was NO WAY I was going to pay a mechanic to do what appeared to be a very easy task. It arrived on Friday and I did the replacement in time to meet the kids to buy them lunch, (Naturally).

I did have to buy Fuel injectors for two reasons. The ones I had would not seat properly and I was having fuel issues. I had replaced the fuel pump that was buried in years of dirt and the fuel filter. I still had stumbling issues so I figured the injectors were affected by the amount of dirt. I was correct. The injectors had a layer of grit on the inside of the manifold. $69.00 for 8 on Fleabay instead of $69 for 1 at the parts store.

I recommend when the old intake is removed to use a shop vac to remove as much of the spilled coolant as possible and clean up the ports for a good seal when you install the new manifold. Torque on the bolts is 18 lbs. My wrench goes down to 19 so I torqued at 20 and called it good. Make sure all vacuum lines are connected. My new manifold had a different location for the rear vacuum line. It was a 90 degree plastic piece that attached without a gasket and I found that it was a major vacuum leak. I little JB Weld around it and let it sit over night and problem solved. You may have to clear the check engine light as I had to. It may illuminate due to lean issues. That is the Fuel rail being removed and brand new Injectors. First time it ever happened to me, but it happened.

I hope this information helps someone and you have a good day knowing that this may be your final resolution to a mystery coolant leak on a 2001 5.4L Ford engine.

 

Thanks for the follow up!