My lbz has a leak that has been running down the bellhousing only when cold. Resealed oil cooler, checked turbo lines, upper radiator hose is not hard in the morning. I have searched everywhere and this leak is driving me insane. What else could possibly be leaking coolant?
LBZ Coolant leak dripping on front driveshaft
- Thread starter LBZ_tom
- Start date
Could be a Rear Freeze plug or it could be something leaking in the engine valley thats running out the back side of the engine.
Get a coolant leak test kit. With the engine cold, pump the cooling system up to 20 PSI. Now crawl around and look for the leak. It will be easy to spot. I've done this several times, adding pressure when the engine is cold is really convenient, since seals and everything are still loose, and you don't burn yourself reaching around/under things to check for wetness.
Valley can be head gasket, but it can also be turbo coolant feed or return, cracked turbo center section (never heard of this but theoretically possible), EGR cooler feed or return, the cooler itself, thermostat gaskets, coolant crossover pipe gasket, or the heater core feed or return. You might have to borrow a borescope and look around for the leak, as you can't really get your hands down in the valley.
You only want one stiff hose in the morning and if what you said is true about your Dmax hose being soft , then it is less likely a head gasket and more likely one of the other things DAVe said !
I see he found the leak, but for information the head gasket can not leak towards the valley as that is where the push rods and oil pass there is no coolant passage on the upper portion of the block or head to seep out.
There is also coolant dye that works like ac dye pour it in pressurize the system and look with the black light :thumb:
Cracked rear cover coolant leak
Glad I found this thread... thought I had a leaky oil cooler elbow..? Ok, I kinda did. Hung new gaskets and it was dry - for about 5 minutes.
Leak reappeared so I Sprayed everything down with brake parts cleaner to dry it up & re inspect. Oil cooler elbow was eliminated / no leaks on new elbow gaskets??? Started the truck and started snapping pics in places the eye couldn’t see. Cracked in the same place as quoted above!
Replied so others could have a look - As Always!!, A big thanks to everyone on this forum - Can’t tell you all how much help it is to have this info and the collective of everybody knowledge and experience(s) at my fingertips!!!!
Glad I found this thread... thought I had a leaky oil cooler elbow..? Ok, I kinda did. Hung new gaskets and it was dry - for about 5 minutes.
Leak reappeared so I Sprayed everything down with brake parts cleaner to dry it up & re inspect. Oil cooler elbow was eliminated / no leaks on new elbow gaskets??? Started the truck and started snapping pics in places the eye couldn’t see. Cracked in the same place as quoted above!
Replied so others could have a look - As Always!!, A big thanks to everyone on this forum - Can’t tell you all how much help it is to have this info and the collective of everybody knowledge and experience(s) at my fingertips!!!!
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Flywheel housing, engine rear cover, adapter plate, a few names used for it
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