Coolant Leak

[Juggernaut_7]

I have a coolant leak that's very hard to find. I've had it at a mchanics shop ( not a diesel guy ) he had said it was behind motor at back of egr when pressurized but I done the whole egr delete myself. I did refill it all with prestone 50/50, I have since been reading you can't use that? But this leak was before I refilled?? I ordered a coolant system kit to pressurize it myself. I like doing my own wrenching and anyone has some advice I'd appreciate it? Coolant seems to end up dripping around oil pan.

 

[Juggernaut_7]

Well I got my universal coolant system pressure tester in and I tested secondary system and everything looked good, so I move on to primary and the kit doesn't have the right lid to screw on. Go to parts store and neither do they on their kit. So I improvised and got it to pump to 10psi and coolant was coming out of and around cap. 16psi cap should not do that at 10psi correct? That's the only leak I could spot.

 

[01wj]

I think that coolant may cause some issues I believe with no protection against cavitation. Although I have a 6.4 I imagine the principle is the same. Maybe someone who knows a little more than I could explain

 

[Juggernaut_7]

I've done some research on that. Supposedly ford wants their coolant for egr and oil cooler reasons. Something about keeping it from corrosion, I have no egr as I have deleted it and I would change it if need ve but this leak was prior to the coolant change.