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Anonymous01/06/26, 15:05No.2969367help needed with engine head
Need help/advice.
Symptoms were:
-loss of compression on pistons 2 and 3
-gurgling sound heard inside cabin (sounded like air bubbles in the water running through the heater matrix)
-some white smoke exiting the tail pipe. Not a lot of it
I've removed the engine head, convinced that the gasket was burnt. It seems fine (see second pic). Now, I have to buy a new gasket (I was counting on this) but, because the old one doesn't seem burnt, I don't know the origin of the problem. So I could end up reassembling the entire thing, just to find out the problem is still there. Help
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Anon01/06/26, 15:08No.2969368
Gasket in his pic.
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Anon01/06/26, 15:09No.2969369
The other layer of the gasket (it's a MLS gasket)
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Anon01/06/26, 16:06No.2969387
Were you actually losing coolant or did you just hear gurgling sounds? You can get kits at parts stores that test for exhaust gasses in the coolant. If there is none then I guess you were hearing something unrelated. Loss of compression and the white smoke does sound like a head gasket problem though. Any chance the head itself is cracked? How do the valves and guides look? Hard to tell from the first pic but the valves in the middle two cylinders do look like they've seen some steam. How do the tops of the pistons look?
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Anon01/06/26, 17:18No.2969404
Check the head for flatness and if it's not acceptable, then grind it with a big piece of sandpaper and a large flat tile. (there's a bunch of decent videos of how to do this on youtube).Using a leakdown tester might have helped to diagnose the issue before disassembly, but it's a little late for that now.
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Anon01/07/26, 00:46No.2969456
What's the engine? It's not a ford ecoboost, is it?
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Anon01/08/26, 00:04No.2969669
id clean it up. scuff it for grip. and glue i the gasket with permatex copper headgasket sealant. then probably sell it pronto
and quit running straight water for coolant you cheapnigger. antifeeze ain expensive and rust growth fucks all sorts of shit up
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Anon01/15/26, 15:03No.2970946
OP here.
We ended up not machining the head, because the machinist said it had no warp at all and we could never make it this flat if we tried to skim it.
In the meanwhile I measured the gap between the pistons and cylinders. See pic.
The gap is huge: 0,4mm at least. Haynes says it should be around 30 -40 micrometers
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Anon01/15/26, 15:05No.2970947
Also, in picrel you can see the segment through the gap. You can actually push the piston back and forward. The left-right gap seems to be around 0,2mm. Any thoughts, anyone?
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Anon01/20/26, 17:01No.2972045
>-gurgling sound heard inside cabin (sounded like air bubbles in the water running through the heater matrix)
If the engine has an EGR valve, replace it in the process. They don't last more than 75k miles and will make this noise or sound like you have an exhaust leak.
You can temporarily fix the noise by cleaning the EGR valve with brake cleaner.
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Anon01/21/26, 16:37No.2972201
Ask your mom, she is an expert at giving me a head. She had nice and tight compression as well. She really enjoys my piston.