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Took it on the highway just now to see if the bleed did any good, no joy. Overheated pretty fast this time. Turned the heater on and noticed cool air coming through, I increased the revs and hot air started. Could be a blockage? The sound of water swishing is present on startup, very little white smoke now. Could’ve been coolant residue from the 3 coolant flushes. Anywho I’ll ask for an actual leak down test or refund tomorrow.
After the engine is fully warmed up and has been running for a while, shut the engine off and feel the lower radiator hose. It should be hot; if not, the radiator is most likely plugged up. Also when the engine has cooled down, start the engine up; remove the radiator cap. Insure the coolant fills the filler neck. Now look for a continuous showing of air bubbles which indicate a head gasket breach. You can also perform a radiator pressure test with a tool for that purpose; pump the pressure up to around 20 psi. It should hold for a long time; if it drop off quickly in just a minute or so, there's a breach somewhere; most like the head gasket.
 

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Discussion Starter #22 (Edited)
Yea well apparently a coolant pressure test passed. But after yesterday’s shenanigans I don’t know which mechanic I shouldn’t trust! I have felt the hoses before, and lots of bubbles especially when revs up, it appears to related to high speeds or high revs. I’ll buy some test strips online today to test exhaust gas. My made says this, what do you think: ... Chiped valve inlet port- & slightly bent valve- when engine warms, valve stem expands & causes friction raising temp, white smoke from valve edge leak ( get d same with valve stem guides perished on old cars when not used long time - they r hard rubber n dry out n leak)
 

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what do you think: ... Chiped valve inlet port- & slightly bent valve- when engine warms, valve stem expands & causes friction raising temp, white smoke from valve edge leak ( get d same with valve stem guides perished on old cars when not used long time - they r hard rubber n dry out n leak)
Very contorted. Occam says it's a head gasket. Have you checked for shiny pistons yet?
 

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Discussion Starter #24
Hrm yea ok, no sir not yet I’ve not had the time to buy a spark plug tool... was kinda counting on the mechanics - can do today
 

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Discussion Starter #25
Ok finally got a spark plug socket, I don’t really know exactly what you mean by clean, none of them seem to be clean, there’s one which is a little bit cleaner than the others, tried to video it check it out, it’s the cleanest crown and another on;
 

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Discussion Starter #26 (Edited)
Also there’s not much white smoke anymore, no milky cap. When the engine is cold and the radiator cap is off, there not much swirling going on, things seem quite still unless I rev the engine a bit
 

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Discussion Starter #27 (Edited)
Ok so once the fan kicks on the bottom hose gets hot.

just went for a short drive again, temp went to the first line near the hot symbol after about 30mins, turned the heater on and drove home, noticed the heater blows cold air when stopped, as soon as I start going again, hot air. No white smoke, no milky cap, some bubbles. Confused.
 

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Those cylinders look pretty normal but I don't see any "texture" to the carbon, meaning it may be recently deposited. Was the carbon in the other two significantly "lumpier" or more textured? Also, were the plugs in those two a different color, and are those two cylinders adjacent? The reason I ask is because the heater blowing cold at a stop means the system has air at the top. Coolant leaking into the cylinders will cease when the level in the block gets low enough, allowing "normal" carbon to re-deposit and putting a stop to any smoke. However, pressure from the blown cylinder(s) will continue to push into the coolant (the bubbles you're seeing).
 

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Discussion Starter #29 (Edited)
The carbon build up in the other 2 looked exactly like the second crown in the video, nice and black. The one that stood out had a cleaner bit I tried to show. The 2 in the video are not adjacent, it’s number 2 and 4. Every drive I’ve been topping up the coolant at the radiator all the way to the neck, I lose about a pint per hour drive or half that if it doesn’t overheat. I’ve only driven it lately to test it. I would say if there’s a leak, cylinder 2 is guilty, which is the first in the video, does it look very clean? The plugs looked all the same, dry, blackish. Apparently they need a 1.1mm gap, to my eye it was much bigger than that, I’ll get a measurement coin today. Here’s another try of the cleanest crown:
 

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Discussion Starter #31
Yea the upper right.. damn. Thanks for your help. Very much appreciated. I’m surprised 3 different mechanics didn’t have a look themselves. I would’ve thought $1500 revenue would be good for business!
 

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Discussion Starter #33
Ok guys a 4th mechanic has taken a look at it and is a bit confused I think.
First he was like, do the bubbles stop? I said no, he said, yep blown headgasket.
Then he hooked up the coolant pressure tester, pumped it to 20psi and after about 5 mins the needle moved down maybe 2psi.
He said, ok so if the water is leaking in the block we will see white smoke on startup.
Started it up and revved the [email protected] out of it, no white smoke.

Then he says yea it looks like a good car but I bet the headgasket is blown. Then says he doesn’t have time to do it for a few weeks.

So 3 mechanics say the different tests pass, 1 says it’s the radiator, 1 the gasket and the other one is unsure.

At this point I’m a bit lost and looking for some direction please.
 

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If it was the radiator leaking you would see it leaking and there should be steam. If you didn't see actual drips there would be white dried residue on the leak area.
I say head gasket, no doubt.
 
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Then he hooked up the coolant pressure tester, pumped it to 20psi and after about 5 mins the needle moved down maybe 2psi.
Did he top it up and bleed it before testing? If not, the water level was probably below the gasket and all that leaked was air. My very clear bet is a bad head gasket.
 

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Discussion Starter #37
He topped it up but didn’t bleed it. You’re probably right, I’ll buy a block tester and test for exhaust gasses. Could a failing water pump seal cause bubbling? I’m doubting because of the lack of white smoke and milk, and the problem started only after I flushed the cooling system myself, I tried to flush the system from the top and it wasn’t working, maybe the 4bars of pressure damaged the water pump seal? I drove up the mountains before I had overheating with no problems, I flushed the system because it had the wrong coolant in it.
 

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Discussion Starter #38
I put on a new radiator cap and almost straight away noticed a fresh coolant smell. Drove for 5 mins, overheated a bit, heater on, went home. Opened the bonnet and damn I’ve never seen it bubbling so bad, coolant everywhere.
 

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He topped it up but didn’t bleed it. You’re probably right, I’ll buy a block tester and test for exhaust gasses. Could a failing water pump seal cause bubbling? I’m doubting because of the lack of white smoke and milk, and the problem started only after I flushed the cooling system myself, I tried to flush the system from the top and it wasn’t working, maybe the 4bars of pressure damaged the water pump seal? I drove up the mountains before I had overheating with no problems, I flushed the system because it had the wrong coolant in it.
Could the piston be above the head gasket when he tested it?
It could be the reason it didn't lost any pressure.



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