2006 Jeep 4.0L just got a new head gasket and hoses - now finding I'm losing anti-freeze at the rate of approx. 1 qrt. per week "somewhere" ... I say somewhere because I find no visible leaks on the ground underneath . I checked the oil and it is fine - no "chocolate milk" appearance to the oil on dipstick or anything out of the ordinary that I can see inspecting the dipstick . Passenger side floor board is dry , so no visible signs of a heater core leaking on the inside ... Where to look next ?? I'm left scratching my head over this one !
Losing Anti-Freeze ... Help !
- Thread starter ChrisD46
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take the spark plugs out and look for 1 with no or different deposits.
alternatively, open the radiator cap, start the engine and watch for bubbling...
alternatively, open the radiator cap, start the engine and watch for bubbling...
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There are a few ways to find coolant leaks. First get yourself a UV dye kit with a flashlight style UV light, these kits are an invaluable diagnostic tool for all types of leaks. Put dye in the system and run it so it is circulated throughout the system, keep the heater on full and on defrost.
Pressure test the system with the engine off and cold, spark plugs out. Pressurize to 20-23lb and watch for the the pressure to drop, keep pressure on the system for about an hour while you look for the leak with the UV light especially down the plug holes.
If there is nothing showing in the cylinders check the rest of the system externally, pay attention to the hose connections and radiator, it not uncommon for a tool to hit the radiator during a big job like a head gasket (that's why its a good idea to always put a piece of cardboard in front of it if its not being removed).
Try looking at night or in a dark garage if you have a hard time seeing it. Check the floor inside and windshield for UV.
If no joy repeat with the engine hot, be careful removing the cap.
An emissions test exhaust sniffer can be used to detect CO in the coolant by just letting it sniff the coolant with the ca removed.
At that rate you would see it in the oil if it were leaking from the HG into an oil passage but a UOA for coolant is a good idea whenever this sort of repair is made and unseen coolant loss is present.
Edit: if minor traces are seen in a cylinder try re torquing the head and manifold bolts (if its a wet manifold) bolts first and retest before ripping into it.
Pressure test the system with the engine off and cold, spark plugs out. Pressurize to 20-23lb and watch for the the pressure to drop, keep pressure on the system for about an hour while you look for the leak with the UV light especially down the plug holes.
If there is nothing showing in the cylinders check the rest of the system externally, pay attention to the hose connections and radiator, it not uncommon for a tool to hit the radiator during a big job like a head gasket (that's why its a good idea to always put a piece of cardboard in front of it if its not being removed).
Try looking at night or in a dark garage if you have a hard time seeing it. Check the floor inside and windshield for UV.
If no joy repeat with the engine hot, be careful removing the cap.
An emissions test exhaust sniffer can be used to detect CO in the coolant by just letting it sniff the coolant with the ca removed.
At that rate you would see it in the oil if it were leaking from the HG into an oil passage but a UOA for coolant is a good idea whenever this sort of repair is made and unseen coolant loss is present.
Edit: if minor traces are seen in a cylinder try re torquing the head and manifold bolts (if its a wet manifold) bolts first and retest before ripping into it.
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Transmission oil coolers often use one side of the radiator for cooling. But, a leak of that size would muck up your radiator fluid quick with a rusty brown/red tint. My last car had this issue and it was first seen as floating droplets of oil on the surface of the expansion tank. If you have a manual trans, then this isn't a source.
Can you shed some light on to why it just had head-gaskets? You really need to check the Radiator/water pump very good. Just not seeing anything on the ground isn't good enough. I cant tell you how many issues I had with Jeep water pump/radiators. They got so bad at one point we always recommended both at the same time. Make sure you look very hard at the bottom of the T-stat housing. I don't know what it was but the housing were another source of leaks after a repair.
Originally Posted By: Warstud
Could be an Intake Manifold leak. Sometimes hard to detect because the coolant burns off as it leaks out.
Here's how to check >>>
Not on a Jeep 4.0. But I've changed over a 100 + of those blazer intake gaskets.
Could be an Intake Manifold leak. Sometimes hard to detect because the coolant burns off as it leaks out.
Here's how to check >>>
Not on a Jeep 4.0. But I've changed over a 100 + of those blazer intake gaskets.
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Nick1994
$100 site donor 2024
Check the freeze plugs
Yes , I would rather find the source of the leak ...
Originally Posted By: Run
I would avoid any stop leak like the plague. I seen what that stuff will do to the insides of your coolant passages. It ruined my friend's engine because the previous owner thought stop leak would fix every leak.
Originally Posted By: Run
I would avoid any stop leak like the plague. I seen what that stuff will do to the insides of your coolant passages. It ruined my friend's engine because the previous owner thought stop leak would fix every leak.
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