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Discussion Starter #1
Ok, I finally got back to the pull a part today and picked up another '84 Maxima Head. I need to replace the valve guides, but can probably just lap the valves. Now, my question is: Can I just get a set of guides for a 280Z or ZX and run with it... or are they different for this head? Thanx in advance.
 

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You'll probably have to recut the seats after replacing the guides, the seats most likely won't be centered anymore. What happened to the guides? It's pretty unusual for them to be worn out.. How much side clearance do they have?
 

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Discussion Starter #3
Well, somehow or another, the rope I was using to secure the head to the side of my truck bed broke in transit (the rope was kinda old), so it slid off of the old towel I had it riding on and actually bent a couple of the exhaust valve stems. I took out the valve retainers and most of the valves, but a couple seemed "frozen" in place, and very hard to pull out. I looked a little closer and felt with a bare hand, and there were what seemed to be very small barbs around the cut for the retainers at the top of the valve stem... needless to say, I think I may have scratched up a couple of the guides (guides, seals, whatever they're called). I don't know how big of a deal this is, but I'd rather have a good seal between the head and the valve stem than deal with fouled plugs and a smokey start all the time. I just wish I'd caught it before I pulled the valves too far down into the guides. : (

Luckily, as far as valves are concerned, I do have that worthless cracked head I bought on the last trip to pull a part, and the valves are already cleaned and in great shape, so I can reuse them.
 

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You mean the rubber part? That's what seals the oil. And yes you should replace them. The guide is the metal tube the valve goes into.
 

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Discussion Starter #5
Ah... I see now. I didn't even notice that there was a rubber seal on there. I suppose it's at the top of the guide... Anyway, what should I do if the guides for those particular valves are scored inside? I don't know if they are yet because it's 1:30 am here, and I'm definitely not feeling up to opening up the shop again this late...
 

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I wouldn't sweat it. Just get some new seals and see how a good valve feels. The seal is what controls the oil. Replacing the guide is a machine shop type thing, don't attempt that yourself!
 

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Discussion Starter #7
Cool. Thanks very much Steve. I didn't want to do it if it wasn't necessary. I'll check it out in the morning after I clean up my intake ports... heck, I might even go ahead and polish them up a bit =o)
 

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Main thing is get a dremel etc and clean up the trasition beween the valve seat and the port/liner. Especially on the exhaust side of a round port head. A "polish" -might- give you 1/2HP? This other will actually do something.
 
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