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Losing lots of water coolant!

2K views 9 replies 7 participants last post by  Astrofarian 
#1 ·
My 2003 Safari 4.3 v6 is losing about a gallon of water every 200 km. Funny thing is, until the unit is very hot, you really do not see any "puddles". I do know for sure the Heater Control Unit is leaking and/or the hose/connector to what (I think) is the front heater core. I get no rear heat either (have not for at least a year). I am resigned to replacing the Heater Control Valve and I will replace all the hoses (this Van has 420,000 km).

The first pic below is a close up of the Heater Control Valve (6 outlet) type, showing the obvious leakage. The leaking hose is the "lower" which "seems" to run to Heater Core. It looks like I will for sure need a special tool to remove those clamps? You can see (to the right) the "bolt" that holds the unit to an arm. Should I resign myself and replace the heater core (I do sometimes smell cooking water) at the same time? This looks like a pretty tough job due to space constraints, I certainly do not want to even touch the A/C Collector as I just had the A/C fixed! That A/C unit seems to be blocking access to the HCV?

Finally, the second picture is a small pool of water after 15 minutes of idling, I see no vapour or steam and I have good power from the engine (I love the 4.3 engine!) . Does anyone think that little puddle is beyond normal? Please keep in mind I had the Safari on ramps, so gravity works, eh?

Thank you in advance to all!


 
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#3 ·
NO PUDDLE is the only "normal" puddle. Get busy.....coolant leaks only get worse....never better. Just out of curiosity, at 420000 miles, you MUST have changed the intake gaskets at some point? If not, plan on doing them sooner, not later!
-M!ke-
 
#5 ·
Thank you for the prompt replies and Happy and Safe 4th to my American friends.

RE: mileage . It is 420,000 km not miles, so this vehicle has 260,000 miles.

Rear puddle: The head gaskets were replaced at about: 220,000 miles. I am pretty sure the INTAKE GASKETS have been replaced and will check. I am leaking oil as well. I am going to do a good engine wash etc... and review all of this.

Wheel well: There has been reference to"removing" the front wheel/tire and then removing the "wheel well cover" - i Had my vehicle on ramps, my wheel wells are metal and seem to be welded on as part of the unibody? I did see some flimsy plastic "flap guards" but they certainly did not appear to do much.

Heater core and Thermostat: For the cost of labour -- I think I will replace both, and maybe even the water pump.
 
#6 ·
The water pump is a HIGH failure item and really for a young person ain't bad to replace. I drove an Astro as company vehicle and at 98,000 miles the DEXCOOL started leaking. I took to dealer for investigating and repair.$$$ they told me it was the intake gasket (Bastards) so the dumb management parked the van not fixing it. I acquired the van years later to find the water pump was the culprit. I have heard about the intake gasket many times but please examine the water pump first. Fill it full of water run until operating temp. shut of van look at water pump area from underneath while it is hot chances are you will feel water dripping from the water pump shaft which is behind the pulley. Also look for stains on engine if it has been leaking for awhile. DON'T replace the dexcool junk use the old standard antifreeze that has been around and proven since the 1940's. Just don't let your dog or family member drink the koolaid. use common sense. grab a hold of the fan blade with serpentine belt off and ANY wiggle you can feel up,down, or sideways the pump is fried 4 bolts and a wack with mallet it is loose. BE sure to clean, clean and clean again the gasket area on the block until it is spotless. install new one and bleed the system while filling. I would replace the thermostat too whilst that far into it. AND if your that far remove the EGR assy and CLEAN clean it spotless too. Take a couple days and just do it slowly you'll be glad you did.
 
#7 ·
I just replaced my heater control valve a few weeks ago. Its not that bad of a job, I removed the intake and upper fan shroud and had plenty of room to work. Also check your vacuum lines too, mine were dry rotted all to hell.
Heater core is pretty easy too, you get to it front the passenger inside area. Pull a few panels and its right there.
 
#8 ·
zipwood said:
I am going to do a good engine wash etc... and review all of this.
Great idea! Get/borrow/build a pressure tester for the cooling system, it's a whole lot easier and safer to find leaks without the engine hot/running.
 
#10 ·
Re: my intake gasket inquiry-you indicated that the head gaskets had been done. The intake gaskets would have been done at that time so nothing to "look into". Get a water pump, t/stat and housing and GREEN antifreeze/coolant. Do your engine scrub and shampoo then get after the heater valve, and other cooling system parts.
-M!ke-
 
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