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1)Yes it pulls right out. The dowel pins might give it some resistance but it should just come up. Make sure you don't lose that o ring that sits between the head and timing cover just beside the part where you have to make a circle rtv.
2)Yea water can come in thru the headgasket and the pistons are just simply pushing the water up.
3)Resurface the head and have the valve seals replaced at least. You can always get it rechecked and get a valve job if you want to, but in most cases no.
4)They will resurface it to specs (assuming it's a reputable machine shop) which means they will only take off what's necessary which is sometimes just a few thousandths of an inch (0.0001"). The bolts will fit fine.
 

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1)Yes it pulls right out. The dowel pins might give it some resistance but it should just come up. Make sure you don't lose that o ring that sits between the head and timing cover just beside the part where you have to make a circle rtv.
2)Yea water can come in thru the headgasket and the pistons are just simply pushing the water up.
3)Resurface the head and have the valve seals replaced at least. You can always get it rechecked and get a valve job if you want to, but in most cases no.
4)They will resurface it to specs (assuming it's a reputable machine shop) which means they will only take off what's necessary which is sometimes just a few thousandths of an inch (0.0001"). The bolts will fit fine.


Hey Nismo thanks for the input. I've had this car for awhile it had 15k miles when I bought it and it was eating oil. As I understand it's an issue with some models, what can cause that, the rings or the valves if it was like that new. Thanks again.
 

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Read up on the QR precat. The precat gets blown up then the engine sucks it back up during valve overlap scarring the walls.
I did and they mention that 1st gen QR was changed in the 3rd gen Altima and 2nd QR in the 4th gen Altima. Would that be 2004 and second QR in the 2005? Anyways mine had the oil consumption back in 2006 when I got it. Didn't do the reflash of the ECM but it drove fine, ate some gas then gave me the 420 code used an extension on the new O2 sensor I bought and it went away. Car had an issue with the serpentine belt slapping and the tensioner making weird sounds. I bet that was from the engine missing or lowering idle. And now the water issue and finally the head. They say the 4th gen have chrome molly rings, liners don't know if that's mine but it ran fine for 135k. I just hope the head job will take care of some of the issues and maybe some new headers.

One more thing I forgot to ask any pointers on how to loosen the bolts for the 2 sprockets without turning the cams/crank to take it out of timing if the chain is loose? Thanks.
 

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1)Yes it pulls right out. The dowel pins might give it some resistance but it should just come up. Make sure you don't lose that o ring that sits between the head and timing cover just beside the part where you have to make a circle rtv.
2)Yea water can come in thru the headgasket and the pistons are just simply pushing the water up.
3)Resurface the head and have the valve seals replaced at least. You can always get it rechecked and get a valve job if you want to, but in most cases no.
4)They will resurface it to specs (assuming it's a reputable machine shop) which means they will only take off what's necessary which is sometimes just a few thousandths of an inch (0.0001"). The bolts will fit fine.

Quick question I am at the part where I remove the 2 sprockets. I marked all is good I took out the intake and the chain lowered. If I take out the exhaust sprocket do I need to hold up the chain? I don't want it to jump teeth at the bottom, and I forgot to ask. I am waiting for an answer before I move forward. Thanks
 

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Crank sprocket cant jump teeth as long as the front cover is installed.
Thanks, I finally took out the head and come Monday I will take it to a machine shop. I did not notice any marks on the cylinder walls, nor any hairline cracks. I wanted to ask a few questions.
1. There's a O-ring the is on the side of the head and it goes into the chain cover. It came apart and needs replacement. Where can I find it or is it part of the gasket set?
2. What RTV should I use?
3.What head gasket
4. Are the torque specs given on page one good for tmy 05 Altima 2.5S QR25 engine?
 

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1. I went to the dealer for this one.
2. I also used the Nissan rtv which is the bomb btw but I imagine you should be able to use a high temp silicone rtv.
3. Depends on your application. OEM is fine for a dd, there's also the option of going ajusa or cometic thru 2J.
4. Grab the fsm for your year and stick with that. You will need to use a angle gauge adapter as well.
 

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1. I went to the dealer for this one.
2. I also used the Nissan rtv which is the bomb btw but I imagine you should be able to use a high temp silicone rtv.
3. Depends on your application. OEM is fine for a dd, there's also the option of going ajusa or cometic thru 2J.
4. Grab the fsm for your year and stick with that. You will need to use a angle gauge adapter as well.[/QUOTE]



Quick question besides the obvious areas where else do I need to put RTV on the camshaft 3 bolt cap?
 

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OK so I did put the head back and an unfortunate thing happened the guide for the exhausted sprocket got pushed in when I put the sprocket back on the exhaust camshaft so when I spun the engine the sprocket was spinning not the cam. Long story short the timing was lost there was very small damage to the side of the head that the machine shop helped me with. But now I took of the entire chain cover by lowering part of the oil pan.
My question is how do I get it to lower completely, I mean the exhaust side detached, the part under the chain cover lowered as you can see in the picture, but the intake side is not lowering that much. I took off all the bolts from inside and the 12 from outside. I even took off the 4 star E14 torx bolts that hold the big square piece. That was supposed to lower that piece(don't know what it's called maybe something to do with the balancer see 1st pic). I already ordered new chain and accessories so I can do it right. But I need to know how to lower the pan more to use RTV on it? Is there a trick to moving the pan down or is it just the old silicone gluing it? Thanks in advance for any help.
 

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I can't remember but is the pan loose? You didn't miss any bolts did you? It should just pop right out. There is no gasket between that and the bedplate, just rtv.
The pan is loose as you can see, but the intake side is still somewhat on. What about the 4 torx bolts that I show in the picture inside the pan? Does that piece need to come out?
 

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Any idea where I can get the 3 O-rings marked in the picture? They are all flat. Is it a dealer only item? Everywhere I tried that has full sets it didn't come with the smaller ones for the oil pump. And I also put a question mark on the left side of the pic cannot remember if there was an o-ring there. Thanks in advance.
 

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Hi guys just a heads up I finally finished putting everything back together, and it starts up fine blew some white smoke for awhile but it does have an issue.
The RPM at idle goes up and down from 1k to 2k. Don't know if it's from overheating before, water in the cyls or what. Didn't check for a code yet. I do have the ALLDATA soft and was able to print out the diagrams to finish the job so I don't look foolish asking a question every time I am stuck.
There is also the temp that went up briefly while driving around the neighborhood, went all the way up but once but I quickly parked and it went down at idle. The heater blows cold still so I proceeded to fill the radiator all the way.
If you guys can think of anything with the idle and maybe the heater blowing cold (which I know there's a procedure to get the air out) I'd appreciate it. Thanks
 

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I jack the front end up as far as possible and let it idle with rad cap off from cold to operating temp. Top it up then turn heater on full blast hot for a few minutes and keep topping up. Little bit of rad hose squeezing might get a few more bubles out during this.
 

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Try doing the idle relearn. The heater blowing cold is because you still have air in there and the hot coolant hasn't gone into it yet. Drive it around more and it should fill it up and cycle in there.
Thanks, I did and redid the relearn, I also had a guy do it with an advanced scanner that does relearns, unplugged injectors turn wheel to the side to get idle down, but it doesn't work, I still get the surge 1200 to 2000 RPM non stop, also 3300 at first start. I put it in gear and it stays at 1100. I did a self made smoke test and nothing showed. No leaks. I don't know what else to do. I did buy another TB and that didn't do anything either. I saw this on YouTube and the guy took it to the dealer. Car drives fine otherwise. So any help would do. Thanks in advance.
 

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As for the headgasket kit....can I buy a full 2007 B16 Spec V Headgasket kit to use on the 04-06 B15? From what I read elsewhere the 07 Headgasket itself is superb to the 02-06 ones? About to do this to mine...had 185-165-170-185 from my compression test :/...it's not smoking up or anything.

For particular brands, like from Rockauto, is EngineTech or DNJ Engine good parts for this build?
 
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