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Av8ferg

L28 from 82 ZX teardown

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Finally got my F54/P79 engine in my garage. I’m going to start tearing it down for a complete rebuild to install in my 77z. Has 164k miles on it and is a guaranteed engine. Was a deal $408 out the door, no core. I might need some help as this happens so wanted to start a new thread for anyone wanting to guide me along.

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Cliff,
Thanks, all great advice. I need to be disciplined because otherwise I’ll have a mess trying to put all the little things back on. Great advice.
Tomorrow I’m going to try and pull the Intake an exhaust manifolds . Charging the go-pro so I can record watch it later Iliad I need to. Already broke my first bolt on the heat shielding between the manifolds.


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Okay, got the manifolds all off without breaking a bolt. Whew!! I let the bolts soak overnight in a penetrating oil and they came off in a breeze.

Here are the first looks at the head and and cam. Looks dirty but I don’t see anything the looks like a problem.


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Awesome! Looks great so far. One broken bolt on an manifold heat shield? You're ahead of the game!

Crack the front main pulley bolt loose before you take the head off. The friction from the valve train will help hold the crank while you loosen the big bolt. And also you won't run the risk of bunching up the chain in a tangle and wedging something. You'll probably need an impact wrench. Do you have one of those?

And then when you go to pull the head, remember the special procedure for loosening the head bolts. And don't break any of them!   :ph34r:

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Copy all. I have 1/4 impact driver but that’s probably not going to cut it. This timing chain looks new to me but what do I know.


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Did the car have 164K or the engine.  That emblem glued on to the engine is not a Nissan factory thing.  It looks like it's a fairly fresh reman.  You might find that everything is almost new.  Might be ready to go as-is.  Stop and think.

Someone ot there has probably seen this before.  @240260280z 

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Or you can thread a couple of bolts into the other end of The crank and put a bar across them locked against the engine stand to stop the crank from turning.

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Good catch Zed Head!  I need to pay better attention.  Didn't even think about that.

I have seen those, on my Camry as a matter of fact.  That head's been rebuilt I bet.  The glue or silicone holding that button on gets too hot and it falls of, voiding the warranty.

"heat tabs"

Image result for heat buttons on engine head

Edited by siteunseen

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164k is not a ton of miles.  Normally a person would measure pressure, do a leakdown test, look at oil consumption, check the cam sprocket notch and groove, etc,  You're kind of jumping ahead Av.

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So the question might be are you rebuilding it for fun or to make it better?  I'd at least check valve lash and the cam sprocket notch and groove, just to see what the wear is on the valve train.  If it's freshly refreshed you'd be wasting money to mess with it.  The cam lobes look new.  It might end up in worse shape when you're done, no offense.

Sorry to the guys looking for internet entertainment.  I'm one of them...

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So, the yard said the car it came from had 164k miles on it. Didn’t have any other info other than the engine was good. I saw that placard in the head and didn’t know what it meant or who put it there.

ZedHead...what is my goal? Two fold, I wanted a replacement engine that had a little extra performance but keep it mostly stock. Sure, maybe I could do the compression test, leak down etc but I wanted to maybe add some performance. Port the head a little, possible shave it like the Captain is doing. At a minimum, I want to pull the head, look over the valves and pistons, see if there is any corrosion or other areas of concern. The engine is sitting in my garage and can’t go in the car for about 6 months (being store in a barn 2 hrs away) while my new house with a massive garage is under construction. I want to know what I have, make some possible performance enhancements and clean and paint the engine. Once It goes in the car I don’t want to them discover issues a few thousand mile later. Don’t it once right and never do it again.

Time is something I have a little of right now and it’s either do this or waste time doing something else.

The chain looks pretty new to me, but the slack seems a bit excessive, what do you guys think? A few video links here. Here is also a pic of the plugs that came out. Got some gunk on them.

Am I making a mistake pulling this head off. I’ll be waiting for some consensus. My new 3/8 impact wrench waiting!

 

 

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1 hour ago, Av8ferg said:

a replacement engine that had a little extra performance but keep it mostly stock.

The chain looks pretty new to me, but the slack seems a bit excessive,

Nothing wrong with that.

The notch and groove is what Nissan created so that you could evaluate chain wear.

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They're all good.  Although I was actually hoping for clouds the other day.  too much UV for me.

To Av, it's easier to evaluate somethings when the engine is assembled.  If you want to keep the unworn parts.  If you're just replacing all of the wear parts then it doesn't matter as much.

You can drill two holes in a piece of flat steel bar and bolt it to the crankshaft to lock it down, for removing the various bolts.

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Okay, Cliff the timing looks spot on but the chain on the drivers side has a slight more that a width of a link of slack. See comparisons.

c9b2416c2ed6c79a443bb8ce9befa9d7.jpg
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ZH, I don’t disagree with the way of thinking. I’m thinking of at minimum pull the head and clean the engine and repaint the block. Maximum is to shave the head and port it. When I flip the engine over and pull the pan I can look it over in there too. At least change the gasket, knock out the big dent in the bottom the yard gave the pan and paint it. I’ll see how it goes but to me this chain is for sure too loose. What say you on the chain stretch?


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Don't assume the previous rebuilder did the best job possible if you have no history on the engine. Chain and guides are cheap, replace them. I'm doing the same build F54 with P79 head, just about finished. Balanced the bottom end after a rebore, head skim, cleaned up the ports, new gaskets etc and full block paint after boiling it out and heat treatment. If you have no idea what was done to it then re do it.

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The notch and groove are a better measurement of chain wear than the finger test.  Even looking at how far the tensioner is extended will tell you more I think.

As far as performance improvements you probably want to consider your engine management system.  The stock EFI system is designed to work with a specific engine.  These aren't like the old carb'ed engines where you just bump up the compression, put a cam in it and some headers and you're done.  You might get more power with some bolt-on mods but it will run like crap for daily driving.

I like a full plan myself, but doing things on the fly is still fun. 

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19 minutes ago, Av8ferg said:

Okay, Cliff the timing looks spot on but the chain on the drivers side has a slight more that a width of a link of slack. See comparisons.

c9b2416c2ed6c79a443bb8ce9befa9d7.jpg
6ef6e767ca7daa7f12f41c8e3e907cc5.jpg
4b45d83c99a0344fd5f10ac912341d53.jpg
a3264cbeee49d2692ef10d2c780171fa.jpg

ZH, I don’t disagree with the way of thinking. I’m thinking of at minimum pull the head and clean the engine and repaint the block. Maximum is to shave the head and port it. When I flip the engine over and pull the pan I can look it over in there too. At least change the gasket, knock out the big dent in the bottom the yard gave the pan and paint it. I’ll see how it goes but to me this chain is for sure too loose. What say you on the chain stretch?


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Are you turning the crank bolt clockwise to tighten the "tight" side before you poke the chain?

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Just to fill out the possibilities - you don't have to remove the head to replace the timing chain and sprocket.  On the other hand, the chain and sprocket might have been replaced when the head was rebuilt, so the head might have that amount of wear.  And, to speedroo's point, a counterpoint - don't assume that you can do the best job possible.  Really, just do the cost/benefit analysis and be aware of the rabbit holes...

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