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TD42 pushing out coolant... Head gasket gone?

13K views 21 replies 9 participants last post by  Sydo 
#1 ·
Hey guys, so in the last few weeks I have noticed the old girl has been pushing out coolant into the overflow and not recovering it into the rad when it cools down.. So I replaced the radiator cap and checked the overflow hose for leaks, still no different. When I take the rad cap off when it is cold (hasn't been started for a day or more) there is pressure in there, even if the coolant level is slightly low.
I also noticed a small amount of bubbles coming out of the radiator with the cap off while its running:mad: so this suggests either my head gasket is leaking or head is cracked?
It doesn't get hot or miss at all when I start it, still runs A1 :confused:
Thoughts?
TIA
 
#5 ·
Yes once I have been driving for an hour or 2 a slight amount of coolant is blowing out the overflow :oops:
Looks like I will be pulling the head off for a look
 
#3 ·
I'm no expert, but if there's pressure in the radiator after sitting cold for a day or so then it seems the cooling system is sealed. That is, no leaks, gasket and head ok?
Maybe it's the overflow tank filling up but not allowing coolant to siphon back?
Is the hose from your radiator going to the correct side of the overflow tank cap, that is, the side with the tube that runs down to the bottom of the tank? Or is the internal tube loose or leaking? Or the overflow tank's plastic cap cracked? Any of the above will prevent coolant from siphoning back into your rad.
 
#4 ·
Well my thoughts are that if it is only a slight leak in the gasket or hairline crack in the head, the pressure in the radiator (0.9bar) wont be enough to force coolant into the cylinder overnight, but the compression is enough to pass though into the radiator when running :rolleyes:
I have checked the overflow hose and it all seems to be ok
 
#7 ·
Mate i had the exact same issue 3 month ago. Pressure when cold and coolant not returning in system. Ended up being the head gasket. My left suspension was full of coolant from the overflow bottle overflowing! Since then and after some $ it's running nice and cold! Good luck


Envoyé de mon iPhone en utilisant Tapatalk
 
#8 ·
So who knows anything about upgrading to head studs while its apart?
Running 32 pound boost and 189rwkw, so might be worth while investment
 
#10 ·
So started to pull her apart, and it appears that the head gasket has been leaking as you can see in the photo there is soot on the intake side between the block and head
 

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#14 ·
So pulled it apart yesterday, the firing ring in the gasket is cracked right where the pre combs are on all the cylinders, and the head has a few cracks too so time for a newy :(
Looks like i will have to go aftermarket head as genuine arent available anymore?
A lot of the bolts on the intake side were nearly jammed in the head with soot that has built up from the leaking over time top lol
 

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