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Dave WM

cam bearing oil feed hole

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I looked at the manual, seemed like it was one of the holes near the center of the head, but my JK pull maxima N47 seemed more like a small hole near the cam chain (looking at the bottom of the cylinder head. I wanted to try to send some oil up that way to see if I could lubricate the cam shaft bearing journals.

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I think that there are two but the FSM only shows one path.  I have an old HG in the garage and it has two copper sealed oil passages, one in the middle and one up front by the cover.  The actual orifice in the block is tiny.

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This was my 1st cylinder head removal from an L engine. the bolts came out quite easy, about 1/4 turn and then they came out with very little effort. I left the manifolds attached (someone had cut off the down pipe right before the connection to a cat I presume). used a JY hoist and an old seat belt rigged up to pull the head out. With it exposed I was able to get at the hard to reach 12mm manifold bolts. They all released easy but I did have the two broken end bolts (big surprise there). The head came right off, no drama at all, the crane made it so easy.  I am now more tempted to remove my test stand engine head to inspect the gasket and water passages for blockage. I have done some research that a N47 head on a N42 block will work but may raise the compression ratio to high. I understand it has to do with the type of pistons used. It would be fun to try it out though with the test stand setup...

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N47 on an N42 block with dished pistons is the 1977 to 1980 L28 engine.  You might be thinking of the late 1980 and up F54 block with flat top pistons.  The N47 head is the same as the N42 head except for the round exhaust ports and liners.

So now you have a spare engine and a spare N47 head?  

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5 minutes ago, Zed Head said:

N47 on an N42 block with dished pistons is the 1977 to 1980 L28 engine.  You might be thinking of the late 1980 and up F54 block with flat top pistons.  The N47 head is the same as the N42 head except for the round exhaust ports and liners.

So now you have a spare engine and a spare N47 head?  

Yea, could not pass it up, figured it would in up in a crusher and I wanted something to play with. The head turn out to be in very good looking condition, pistons crowns all looked about same (no evidence of head leak) camshaft looks good, valves all looked good. will post up a video of it. Had a lot of fun at the JY, looked like pig pen by the time I was done.

Frankly I was shocked at how easy it was to pull after all the horror stories I have read on some others. I got the exhaust manifold as well, it has a place for an O2 sensor that may come in handy.

I was not sure if the block was worth getting, huge heavy, and 2400cc (maxima) Same with the crankshaft, maybe that is worth getting. Just seems to be waste to see them go to the crusher, this yard does not leave things for long.

 

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Sorry, I thought you meant an L28 N47.  The Maxima N47 does have the smaller combustion chamber so would give a higher CR, even on a dished piston block.  Most people call that head the MN47.   I think that one of the valves is smaller than the L28 N47.

It's fuel injection head on a later model car with catalytic converters and O2 sensors, I think.  So it would run cleaner.  The injectors might be worth getting, they're probably the same as the L28 injectors.  Even the whole engine control system if you want to set one up with O2 sensor feedback.  

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I grabbed the injectors already. Roger on the MN47. Not sure what I want to do with it at this time, mainly give me something to practice on. I like to try stuff out on my spare before diving in on my runner. will pack it up and stow for now. think I will pull the two rockers on the depressed valves and wire tie them to the right spot, I don't like the idea of long term storage with the springs depressed (or the valves hanging down for that matter).

I am still on the fence about if the spare has a HG leak, my runner did not change the fluid color at all, the spare seemed change to a lighter shade of blue. has me worried.

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4 minutes ago, Dave WM said:

I am still on the fence about if the spare has a HG leak, my runner did not change the fluid color at all, the spare seemed change to a lighter shade of blue. has me worried.

I think that a good radiator cap and recovery system might tell you something.  When I had an external coolant leak through the HG the recovery system didn't work.  It wouldn't pull coolant back in so the radiator level was always a bit low.  Had to keep refilling.  Of course, you'd only know if you ran the engine every day for a week or two.

You could pressurize the system, cold, and see if it holds.  It's supposed to be a closed system with an ~13-15 psi release pressure.

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You know that was the next thing I was going to try, actually tried it, but my decades old Gates rad pump would not seal, the darn rubber plug as so old it did not compress on the rad neck. So will have to buy a new one.

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found an O ring that solved the seal fit a the neck, have a leak around the T stat housing, guess my homemade gasket aint making it. will get a proper gasket and some sealer and try again when I get in that new 160f stat.

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