Head gasket leak is not very noticeable. But shop said it would cost around $6,500 to fix on my van as the engine would need to come out or get a newer engine. So I am going to reseal with Blue Devil Head Gasket repair 'pour and go'. I didn't want to remove thermostat. But I did notice that the antifreeze is brown like tea. So I did a radiator flush with Blue Devil radiator flush. My question is, on three attempts to drain the antifreeze, I have only seen about 1-1/4 gallons of fluid. My engine has a 2.33 gallon capacity. Between flushings I ran the van for 10 minutes with the heat on full and I did not feel hot air coming out of the console. The reason i brought it in to the shop is that both heat and air did not work. Just had the mixer fixed in the dash. There were also misfires with the leaking head gasket. Where is the extra gallon of antifreeze in my engine? Is it a thermostat problem. Engine does not overheat.
So I am going to reseal with Blue Devil Head Gasket repair 'pour and go'.
Good luck with that snake oil. Maybe if you're lucky it will work for a while. It may not work at all, and if you're unlucky the stuff may plug up your cooling system and make matters worse. For what it's worth Scotty favors the Bars Leaks head gasket product in the silver bottle. Hopefully you don't plan to keep that Sienna much longer (you did not state year or mileage). Those "sealer" products are temporary band-aids at best, to try getting a little more life out of vehicles that already have 3 wheels in the junkyard and the fourth on an oil slick.
How did the shop come to the conclusion that you have a head gasket leak? Was a head gasket test done?
Where is the extra gallon of antifreeze in my engine?
Did you drain the block?
@chucktobias The van has 158,000 miles and runs well besides leak. Have not heard of draining the block. I drained the radiator and opened the bleed valve to get as much antifreeze out. can you recommend a video on draining the block? If I drain the block, will I get the 2.33 gallon engine capacity?
@cmoerschel I am not familiar with your engine. There may be a drain bolt or petcock on the block. Your best bet is to do a web search on draining the block.
But I did notice that the antifreeze is brown like tea.
That coolant should've been drained and refilled years ago. Coolant contains corrosion inhibitors and they break down over time, producing acidic components. Aluminum head gaskets and acidic components in the antifreeze don't mix. As the engine heats up, the coolant's acidity becomes more aggressive.
Have not heard of draining the block. I drained the radiator and opened the bleed valve to get as much antifreeze out.
Pop the lower radiator hose completely off and let it fully drain out. Undo the top radiator hose and use a garden hose to flush the radiator out. Pop the thermostat off and run the hose through the block to flush the engine out. Flush both until the water is clear. You can't cut corners and expect a sealer of any kind to work as advertised. You could very likely end up making your problem worse.
@justin-shepherd Good catch, I missed that "brown like tea" description of the coolant. That's probably why the head gasket failed. If really bad it might have even eaten holes in the aluminum cylinder head.
You're probably right, I didn't think of the heads themselves. Those are more robust than that flimsy head gasket, though.
@justin-shepherd The head(s) would have to be exposed to worn-out, acidic coolant for an extended period of time but I've seen it happen. (Fortunately not on any of my own vehicles.) The old-school cast iron lumps were much more forgiving, not that cooling system maintenance should be ever be neglected.
Makes sense, aluminum is more reactive than cast iron in terms of bonding. This is my basic chemistry knowledge working. Haha.