About to tackle Head Gasket on my 2012 CT200h tomorrow

Yeah, that's a triple square, not bi-hexagon. The angles on the points are different and therefore contact the fastener differently. I've heard of people using them, but the last thing I'd want is a stripped headbolt.
 
Originally Posted by cpayne5
Yeah, that's a triple square, not bi-hexagon. The angles on the points are different and therefore contact the fastener differently. I've heard of people using them, but the last thing I'd want is a stripped headbolt.


Agreed, but usually the triple-square works.

I grabbed the bi-hex from my toolbox and attached a picture below. The differences are minimal.

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I've got the Snap-On (SADM10E for anyone that cares) one, too. Snap-On had a nice PDF that explained why everyone needed to buy their new $30 bit when they first introduced it. It comes down to the angles and the subsequent contact surfaces between the fastener and the bit.

Happy to hear that there's not much chance of stripping the headbolt using a 12mm triplesquare.
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Originally Posted by The Critic
Originally Posted by MPDano
Went to Oreillys to get the proper head bolt tools. $14 total

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Technically, those are not the correct sockets but they will usually work.

Crankshaft rotates CLOCKWISE on this engine, not CCW.

You will need another person to help you with reinstalling the timing cover, so I would plan on having someone around for that part of the process. Make sure the surfaces are surgically clean with zero debris remaining before applying RTV. The RTV needs to be applied in a bead (3mm thickness is what I target). Use FIPG Black.

Also, leave the exhaust manifold bolted to the head. Disconnect the manifold at the donut. It is much easier to do it this way than to unbolt the exhaust manifold in-car.


Yes, didn't even notice the Triple Square until I posted the picture. Seems to fit perfectly and the torque level isn't that high, hopefully.

Question, do I have to remove the Harmonic Balancer to remove the timing cover?

Also, do I have to remove the cams or can it come out with both upper/lower heads attached?
 
On a DOHC the head bolts will be somewhere underneath the camshafts, you almost always have to remove them to reach the bolts.
 
Originally Posted by MPDano


Question, do I have to remove the Harmonic Balancer to remove the timing cover?

Also, do I have to remove the cams or can it come out with both upper/lower heads attached?

Yes, the harmonic balancer must be removed in order to remove the timing cover. If the balancer is stuck, there are two threaded holes that you can use. I think they take M8x1.25 bolts, but please do not quote me on that...

The camshafts can stay in the cam housing, but best practice is to remove them. But you do need to remove the cam housing in order to access the head bolts.
 
Ok, done for the day. Getting too old for this kind of work, laying on the engine, climbing under the car, lol. Anyways, only thing left is to remove the harmonic balancer, timing cover and cams. Then should be ready for the head pull.

Question, looks like someone was in the timing. Marks all line up but the chain link colors aren't on the marks. Turned the motor multiple times to verify. Can someone verify I am TDC?
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They will almost never line up after you spin the engine over for the first time. It takes many revolutions to get the links to line up with the marks. They are for installation more or less. As long as the marks line up their positions in the FSM then you should be fine. It would be wise to mark each cam gear, crank gear and chains on their timing marks for quicker assembly. Your timing marks appear to be in the correct position
 
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All of those marks and the rtv on the timing cover seams are factory. No one has opened this engine before.

You may be in time, but I highly recommend turning the crank until the colored links line up with the marks. Especially if it's your first time doing a job of this nature. It may take 30 or more revolutions but the marks will eventually line up. Removing the spark plugs will make this process a lot easier.

https://youtu.be/9UWD2iNXSQ4
 
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Originally Posted by The Critic
All of those marks and the rtv on the timing cover seams are factory. No one has opened this engine before.

You may be in time, but I highly recommend turning the crank until the colored links line up with the marks. Especially if it's your first time doing a job of this nature. It may take 30 or more revolutions but the marks will eventually line up. Removing the spark plugs will make this process a lot easier.

https://youtu.be/9UWD2iNXSQ4


Yes, plugs we're removed way before I started messing with timing. Lol, I guess I only rotated the crank 29 times. I'll rotate more till I get the colored chain links to line up with the marks. Thanks guys.

Where is the chain tensioner located?
 
Originally Posted by mattd
They will almost never line up after you spin the engine over for the first time. It takes many revolutions to get the links to line up with the marks. They are for installation more or less. As long as the marks line up their positions in the FSM then you should be fine. It would be wise to mark each cam gear, crank gear and chains on their timing marks for quicker assembly. Your timing marks appear to be in the correct position


Thanks Matt
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Found this video on the 1ZZ-FE engine, I am assuming the tensioner works the same way as the 2ZR-FXE motor, and I think I know where the tensioner is located (firewall side of the motor). Anyways, I do like to know the tensioner hook does release on it's own by just turning the engine clockwise and listening for the clicks.
 
Originally Posted by MPDano
... I know where the tensioner is located (firewall side of the motor). Anyways, I do like to know the tensioner hook does release on it's own by just turning the engine clockwise and listening for the clicks. ...
It makes sense that it is on the slack side of the chain, considering direction of rotation.

Amusingly, that tensioner apparently looks and functions almost identical to the one in my 1981 Mazda---although the chain is very different.
 
You might as well go ahead and replace the PCV on the side of the block while you have the intake manifold off. I didn't look back through the thread to see if this was covered, but depending on miles, it might not be a bad idea to replace the timing chain also. I tend to be a "while I'm in here" kind of person when it comes to replacing things.
 
Day 2. Head gasket installed and cams reinstalled and all torqued down, new Felpro seals installed. Head surface verified using a metal flat edge for any warpage. Timing all lined up. Hopefully to button it all up today and give it overnight for the RTV to cure overnight. FYI, top head needs to be removed in order to get to the head bolts.

You can also see on the old head gasket, all the raised ridges are non existent anymore. Hence, opportunity for leaks.

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Definitely a blown spot on #2, #1 and #3 wasn't far behind. Those "raised ridges" are compressed when torquing the head down.

Were there any loose head bolts?

And JMO, it would have been wise to have the head at least resurfaced. Head gasket failures are rarely due to the gasket by itself. Usually due from head bolt torque or surface distortion, even in very small areas....not necessarily across the plane.
 
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