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Discussion Starter #1
New to the z car world working on one for an old friend. She had a bad head gasket so I did some research on the car. It seemed pretty straight forward. We got the head off took it to get checked. Ended up taking .0046 off the head. They cleaned it but did not disassemble it, left valves, cam ECT in it. It's an 82 280zx with 189k miles. I have a couple questions. The milling process stayed under the limit to require cam shims correct. With that many miles on it would the timing chain "stretch" combined with the material removed from the head result in the geometry of the cam being off? Therefore requiring cam shims to fix. Or can I just put a new timing set in. And not worry about the cam shims? I know there is a procedure to check chain slack/wear. The car is an hour away and I just want to cover all angles and be prepared. Thank you

Also I've worked on cars for years mostly domestic. This has been a fun change of pace. In my opinion pretty well designed cars. A little intimidating with what seems like endless amount of vacuum lines. But it came apart pretty easy for having 200k miles. It has held up.
 

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New to the z car world working on one for an old friend. She had a bad head gasket so I did some research on the car. It seemed pretty straight forward. We got the head off took it to get checked. Ended up taking .0046 off the head. They cleaned it but did not disassemble it, left valves, cam ECT in it. It's an 82 280zx with 189k miles. I have a couple questions. The milling process stayed under the limit to require cam shims correct. With that many miles on it would the timing chain "stretch" combined with the material removed from the head result in the geometry of the cam being off? Therefore requiring cam shims to fix. Or can I just put a new timing set in. And not worry about the cam shims? I know there is a procedure to check chain slack/wear. The car is an hour away and I just want to cover all angles and be prepared. Thank you

Also I've worked on cars for years mostly domestic. This has been a fun change of pace. In my opinion pretty well designed cars. A little intimidating with what seems like endless amount of vacuum lines. But it came apart pretty easy for having 200k miles. It has held up.
Most likely need to replace timing chain and guides with that miles. Usually anything over .030 off the head should be shimmed. Most likely with .046 off the head and an old timing chain set would be too much.
 

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Discussion Starter #3
But they removed .0046 in. Not .046 in. That's what the paperwork said. I even called them to make sure that was correct. Spoke to the guy who did it myself. He said the head was in pretty good shape he just took enough off to true it up. So I'm guessing timing set w/o shims.
 

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But they removed .0046 in. Not .046 in. That's what the paperwork said. I even called them to make sure that was correct. Spoke to the guy who did it myself. He said the head was in pretty good shape he just took enough off to true it up. So I'm guessing timing set w/o shims.
Sorry I misunderstood
 

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Discussion Starter #5
I had to double check the amount removed also. So I should be ok to install timing set and no shims? I will check the chain after replacement per the recommended process to be certain. Anyone else care to chime in. Any thing else I'm missing or overlooked
 

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If you have a factory manual just keep the timing marks withing the marks on the cam gear. There is a little _ mark and a notch? Keep them lined up as shown in most repair manuals and you should be good to go. Big thing is making sure you're on the correct cycle of #1 TDC. They show you in the manual and then there are 3 holes in the cam gear that you can select from to align. Start with hole 1. If the notch in cam gear is to the left of the oblong groove _ then go to hole #2. If still to the left then hole 3. Imagine v needs advance to next hole v is ok. Haynes manual for 280zx pub 1987 shows the procedure on page 76 and 77. Make it look like that and you should be fine. Make sure to set the valve clearances and also double check the cam timing marks after you have turned the engine over and it should be ok. Just don't go past the spot you want on the gear and try to back up to it. Always turn to the place you want to be. Make sense?
 
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