Thanks for the reply.

All service has been at the dealer. All radiators are ford oem. I know they pressure tested the system and checked for head gasket leak. I have checked the electrolysis myself. No other hoses have leaked.
I did have the dealer install a transcooler when I bought it in 2001. But other than that. She's
Entirely stock.

I did spray the mounts with silicone to soften them up. Right now the leak is pressure only. Just one drop on the ground. Will hold pressure around 10 lbs but not 16lbs.
Just seems strange to leak in same place all 3 times.
Appreciate any ideas.

 

Yes it is. Maybe there is a chance that the clamp isnt holding? Ive also seen the radiators come with an adaptor sleeve to make one of the hoses fit the smaller radiator neck. Before you replace it again I would have a radiator shop pressure test it for leaks.

Earlier Expedition and F150 did suffer from Electrolysis and I have seen MANY heater cores leak as a result. If you arent having heater core failures then I would pretty much rule out the electrolysis.

Never add a ground directly to the radiator to improve electrolysis issues. That could actually increase electrolysis. Redundant battery ground cables and thorough flushing of the system help the most from my experiences.

 

Thanks again for the reply.

I have had 2 front heater cores replaced in my truck since I had her. The first one they did not put the flow reducer on and the next time the dealer did. No problems for 3 to 4 years. The back heater core shortly after. But none since. during this time though I have gone through 3 to 4 radiators. I will try adding some extra grounds today. From battery to body, battery to frame, and battery to block. However I did check all of them and they appeared fine.

Thanks...

 

Ok I just checked voltage in my coolant. It is .13 Volts. I also checked the grounds. The negative battery terminal to body .5 ohms, negative battery terminal to block .3 ohms and negative battery terminal to frame 0.4 ohms.

So correct me if I am wrong but it does not seem to be an electrolysis problem.

I did notice the the upper radiator support was actually lifting the top hose. I bent it down just a little bit so the hose was self supporting.

Could the bracket have been putting strain on that side of the radiator lifting the hose?

 

Try the hose clamp. It could be letting it leak into that area. If it's the actual seam leaking on two different new ones there is some other issue. Maybe the hose is too short and pulling on the tank. Radiators don't just leak that easy in any one area.

 

I thought the same thing. I replaced the upper radiator clamp with a screw type and moved the hose back a little on the neck. That did slow down the leak. But it continued. The leak was at the seam on the lower right of the radiator. I replaced the radiator and checked the mounts. All looked fine. I did spray them all with silicone to soften them up. I also bent the top mounts just a little so they still supported the radiator but the was a little movement. I replaced the thermostat and cleaned out the degass bottle. There was a lot of debris in the bottle.

I bought a test kit to check for hydrocarbons in the degass bottle. There was none after driving for a week.

Do you think I should replace the upper radiator hose? It is soft and looks fine. But at this I open to ideas.

 

No need to replace it if it's not leaking there.

 

Ok leaking again. Same side of the radiator passenger side. Checked for exhaust gases. None. I am going to pull it down this weekend. I m going to replace the grommets and the upper hose. I think I am going to go with a 13 lbs cap as well.

Any other ideas??

 

Ok had another leak from passenger side of radiator. My front heater core was clogged as well. I have replaced the radiator, front heater core, upper/lower radiator hoses, hoses to the front heater core, and thermostat. The other thing I did was to measure exactly how much antifreeze I drained out of radiator and block. I blew out the block coolant passages with air as well. When I replaced coolant I went with Zyrex G05 straight so I would achieve a 70/30 mix. I verified the concentration by testing it afterwards.

Everything is working well. I place a pressure gauge on the overflow bottle after the truck was hot. The system pressure is 2 pounds. With the old set up it would be around 7 psi. Looking back checking the concentration of the coolant is one thing I never did. I do not know if the dealer ever check that either. This is the first time I have run the Zyrex G05 since I bought her. She came from factory with it.