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cooling system

2K views 8 replies 3 participants last post by  RECox286 
#1 ·
2000 Astro son is driving ran hot the other night, Check engine light, high temp gauge. Placed some 50/50 in reservoir and drove home a couple of miles. Engine roughed, heard tapping sounds in engine. Let set for a couple of days. Checked radiator this morning, had fluid in reservoir but radiator was bone dry. Filled radiator with green coolant. Took 2 gallons, could heard it gurgling as it went down. Ran engine, turned blower motor on with temp on high. Coolant slowing went down, temp gauge slowly went up. Not sucking from reservoir, realized it its clogged with brown sediment. Plan on flushing system today, interior of vehicle has burnt smell. Hope I'm not too late, checked oil dipstick, no chocolate milk signs, no white some out of tail pipe. Keeping my fingers crossed it's not a blown head gasket. Any suggestions, opinions or advice would be much appreciated. Novice at mechanics.
 
#2 ·
I suggest you do, or have a cold pressure test done before you do anything else. Find out where

the liquid is leaking. Could be a simple problem up to a catostrophic one. You have a 2000

model so it should be placarded to use Dexcool, no ? If you added green antifreeze, then you

definitly would need a complete drain and flush. Never mix Dexcool and the green stuff.

Good hunting

Uncle Bob
 
#3 ·
Thanks for the reply, Bob.

Yes, fill radiator with green, 2 gals worth. Realized my mistake from this forum. Flushed system best that I could here in the yard. Now have Dexcool, (and its orange) in it. Drained radiator, filled with water, ran engine with heater blower motor going a total of 4 times. As stated, reservoir was clogged with turned out to be
rust sediment so I may be in more trouble than I thought. Thing is, owners manual say system takes 16 qts. Was lucky to get 8 qts. 50/50 solution. And no heater blowing cold air. Next step will be to have the thermostat changed. For some reason I have the feeling that the water pump might be going. May not be circulating the antifreeze. I know van is leaking power steering fluid but the engine block underneath was damp. Maybe the seal on the pump. Took van for a short ride, temp is still higher than normal (as far as I know) @ 210, but not reaching in the red as before. Know this is all due to lack of maintenance. Come to think of it, time to flush my own radiator out of my 01 f150 with 230,000 miles.
 
#4 ·
It is tough to get 16 qts into the system, when you haven't drained it completely. There are 2 pipe plugs in the block,

one centered on each side of the L and R lower portion of the block. I replace the plugs with 1/4" drain cocks, so it is

easier to drain each side of the block. When you remove the plug, if nothing comes out, probe the hole with a small

pick or screwdriver to bust up the sediment. There is something of a controversy about the good and bad points for

using red or green. Most of the old hands here have reverted back to green, as I have also done. It requires a thorough

flush so there will be no cross contamination, but I believe it to be well worth the effort. Hang in there...

Uncle Bob
 
#5 ·
I wouldn't ignore the pressure test suggested above.

If you don't see signs of your water pump leaking, I'd be willing to bet your lower intake manifold gaskets are. If they are, get the upgraded Fel-pro plastic-coated metal gaskets - it's totally worth it.
 
#6 ·
Uncle Bob,

Have conducted cold pressure test as suggested. Leak is so bad can't get more than a couple of pds of pressure build up. Hear hissing sound from the drivers side but cant see any leakage. Have found major leakage of all places, under the interior dash passenger side. Took off black cover to discover what looks like a mini radiator and that is leaking steadily under pressure. This would explain the burnt smell in the cab. Didn't notice moisture because it was seeping down behind the carpet and floor mat. Any suggestions from this point on? Never realized that piece of equipment was there, not even sure of what it is. Could it be for the rear heat?
 
#8 ·
Don't!

Just replace the heater core. Heater core sealant will clog your entire system, including your engine, and it will end up costing you far more than the goo did.

Just replace the heater core - its neither expensive nor difficult on these vans.
 
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