How low is the coolant level in the radiator?

 

You need to test for combustion gas in the cooling system, especially in an aluminum engine that overheated, pushing coolant out

 

Pressure test for leak after cool down. Water pump is rare for 3.5, look to see if green stuff at chain cover / water pump face. Thermostat, rare, unless cooling system totally neglected.

Low coolant likely cause of overheat, and then to find out where coolant going. After cool down and safe to open system, note coolant level, if way low, fill with water, then have assistant start engine, did it volcano out with engine start, or stay reasonable level.

Had a few V6 that have pulled head bolt threads from block, and cause cooling concerns, they ended up with new shortblock.

 

Pressure test for leak after cool down. Water pump is rare for 3.5, look to see if green stuff at chain cover / water pump face. Thermostat, rare, unless cooling system totally neglected.

Low coolant likely cause of overheat, and then to find out where coolant going. After cool down and safe to open system, note coolant level, if way low, fill with water, then have assistant start engine, did it volcano out with engine start, or stay reasonable level.

Had a few V6 that have pulled head bolt threads from block, and cause cooling concerns, they ended up with new shortblock.

well there is a leak. Radiator took 2 quarts of water to fill. Ran OK after filling and heated up without overheating and interior heat worked. I see some water at the interface between the black housing that the thermostat and hoses go into and I guess the block. I can't quite tell if that housing attaches to the side of the engine? Is there a gasket there that could be leaking? I'll see if I can post a pic

 

BTW I don't see anything in the neighborhood of the water pump so I think that its good.

 

found something else on here about a coolant crossover housing? I'm thinking this is the likely culprit.

Coolant leak 2010 3.5 AWD

We just purchased a 2010 Santa Fe with 110,000 miles on the clock. There is a very slow coolant leak for which I can't find the source. I routinely can see a drip from where the transmission attaches to the engine but can't find the source above. Can anyone offer any suggestions?

www.hyundai-forums.com

 

I would wash it all off with water then go for a drive to heat everything up. After that what is wet is where it is leaking.

 

Not sure how well the pics show it but the leak is in the coolant crossover housing or whatever its called. It's a plastic housing that has a bunch of hoses going into it and encases the thermostat as well. The portion that connects to the block has channels for an oring and the plastic has deteriorated and broken loose so that the oring grooves are no longer contiguous.

 

New part due in today. Going to flush the cooling system a few times to clean everything up and check for leaks after I get it put back together. How much coolant do these take if I drain the system? Is it just normal yellow or one of the specialized ones?

 

Got it all back together and - knock on wood - no leaks.

 

Michael:
Congrats on finding the issue. I see that your coolant looks like it's a color other than green. I realize that color does not matter as long as it meets spec, but our '11 3.5L came with green, so that is what went back in when it was drain/refilled.

On a side note, I was dismayed to learn that the local Hyundai dealer does not use Hyundai brand stuff if they can help it during servicing. I know that mixing incompatible types of coolant can lead to long term damage and headaches.

Please keep us posted on how things progress since the repair. I'm glad that Dog Patch Steve says that the 3.5L water pump is not a common repair, because it does not look to be repair access friendly at all.

Don

 

They have to use OE for warranty repairs, or Hyundai will figure it out they selling more stuff than what they order. We was keeping OE, and using lime green on cheap from O'Reilley, Shell, NAPA for a number of yrs, then Mgr decided we only sell OE, as it keeps stock coming in and going out, make more on OE then part store, and warranty requires OE stuff, or they deny / debit claim

 

Coolant was very brown. It's never been changed so 156k miles and 13+ years of abuse on the coolant. I hope there isn't a head leak somewhere that is getting exhaust into the coolant. I'll test it after a week or 2 of driving, but it drives and runs great still ...

 

Oh my:
The manual calls for new coolant at the 5 year OR 60k mile mark. I had the dealer do it at the 5 year mark, then I did the 2nd one at 10 years. Still looks green.

If what was in yours was green to start with. it was terribly overdue.

Don