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Head Replacement

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Old May 3, 2025 | 01:25 PM
  #1  
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Default Head Replacement

I tried to search for an answer to this question to no avail. I screwed up installing a replacement timing belt on my 06 400h, and most likely damaged some valves. Engine makes lots of clanking noises and it does not rotate by hand freely. Anyway, blah blah. Has anyone removed and reinstalled the heads on this engine while in the car? Utube doesn't show anything. Really the question is how difficult is it to remove and reinstall the head on the rear bank. Any assistance on this would be greatly appreciated. I will be doing a valve clearance/inspection first.
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Old May 3, 2025 | 02:20 PM
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Originally Posted by manix37
I tried to search for an answer to this question to no avail. I screwed up installing a replacement timing belt on my 06 400h, and most likely damaged some valves. Engine makes lots of clanking noises and it does not rotate by hand freely. Anyway, blah blah. Has anyone removed and reinstalled the heads on this engine while in the car? Utube doesn't show anything. Really the question is how difficult is it to remove and reinstall the head on the rear bank. Any assistance on this would be greatly appreciated. I will be doing a valve clearance/inspection first.
Did you replace the timung belt for preventative maintance or did it snap(or slip a tooth).

Reason I ask is because maybe the bad valves caused the belt to fail(jammed valve).

Or maybe not because we don't know yet. 😁
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Old May 3, 2025 | 02:22 PM
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Was replaced for preventative maintenance. Car ran great before I damaged it
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Old May 3, 2025 | 02:26 PM
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Originally Posted by manix37
Was replaced for preventative maintenance. Car ran great before I damaged it
Ok, ok, I was trying to get you off the hook and put the blame somewhere else. Lol
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Old May 3, 2025 | 03:24 PM
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No this is on me...I love this car and was doing some maintenance to add longevity. Engine mounts, plugs, VC gaskets, coils. Now I have a great car with most likely bent valves. I've done several belts over the years, but this one bit me.
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Old May 4, 2025 | 03:07 PM
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Originally Posted by manix37
I tried to search for an answer to this question to no avail. I screwed up installing a replacement timing belt on my 06 400h, and most likely damaged some valves. Engine makes lots of clanking noises and it does not rotate by hand freely. Anyway, blah blah. Has anyone removed and reinstalled the heads on this engine while in the car? Utube doesn't show anything. Really the question is how difficult is it to remove and reinstall the head on the rear bank. Any assistance on this would be greatly appreciated. I will be doing a valve clearance/inspection first.
I'd think its best to remove the engine, as the way its mounted & you have no idea if any pistons are damaged. Yeah,I know its not what you wanted to hear (read).....
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Old May 4, 2025 | 03:35 PM
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Radiator side cylinder head is easy enough, firewall side will be a painful experience your back will hate you.
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Old May 5, 2025 | 10:06 AM
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Thanks for all the replies. I figured it would be a back breaker to do the rear head, but can it be done at all? Has anyone here performed this operation? I'm not really in a great hurry, and if I do a valve clearance on both the heads I may have a good idea of the damages. Also renting or borrowing a bore scope to look in the combustion chambers for piston damage. At this point this has become a long term project and experiment.
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Old May 5, 2025 | 09:56 PM
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Originally Posted by manix37
Thanks for all the replies. I figured it would be a back breaker to do the rear head, but can it be done at all? Has anyone here performed this operation? I'm not really in a great hurry, and if I do a valve clearance on both the heads I may have a good idea of the damages. Also renting or borrowing a bore scope to look in the combustion chambers for piston damage. At this point this has become a long term project and experiment.
that'd be a great idea, as it'd give you a better clue, w/ the pistons.
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Old May 5, 2025 | 10:27 PM
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Originally Posted by LeX2K
Radiator side cylinder head is easy enough, firewall side will be a painful experience your back will hate you.
I'm getting too old for working in the back of the engine.

Anything else back there happens, l'm letting a shop fix it. 😃

Plus, I don't have time for it.
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