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Well, my '78 280z has been running like crap no matter what I do or have done to it. I finally talked to a few different people and told them my distributor is cranked all the way to one side. They said it's more than definite that my chain has skipped a link or even two. Well, took the valve cover off and what not and couldn't quite tell if it had or not. Well, I got a little jumpy and decided to pull my camshaft gear/sprocket. Well, now I've screwed EVERYTHING up! I can't get it back on, let alone in the right configuration. What are my options now? How do I put this back together. It's out in the gravel in front of my house. So hopefully it won't rain much and I won't need to get underneath the beast much. Thanks!!

James
 

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Hi, you'll have fun with this one haha,

what you have to do is this. first, if you drive this car and plan on keeping it for a while, but don't plan on doing major engine mods to it, go and order a new timing chain kit, you might as well replace the whole setup. If you don't want to pull the engine, drain the oil, and coolant. Pull the radiator out to give you room, and i also recomend to take the hood off, only 4 bolts. You have to unbolt the oil pump and oil pan bolts to the front of the engine atleast, and loosen most of them towards the back of the engine. You then have to take your crank pulley out, easiest way is to put car in gear, put on parking break then unbolt the one huge bolt holding it. After that you can unbolt the front cover of the engine. take it out and if you are not replacing the chain components, just slide the chain tensioner back in its place, because that is why you cant stretch the chain out far enough to put the cam ger back on. once you do that, make sure you have not rotated the crankshaft at all or the the camshaft. you can put the top gear back on. If you ant to make sure timing is right, just turn the crank and follow the chain's pollished links. after about 1-6 spins, they should land both on the right side and one on the punch mark on the crank sproket, the other on the cam sproket number, appropriate to the number that is in the cam keyway. I would recomendbringing the valves and pistons to tdc and re set timing. read your chilton manual a coupl of times it will eventually make sense.

Good luck and hope this helps.
 

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I would suggest you get ahold of a friend who is a good mechanic, find out what kind of pizza, beer, scantily clad women, or whatever he likes. Then proceed to get tons and tons of that item(s).

Call him and let him know that you are seriously overstocked in the item he is interested in.

When he arrives, hand him the tools, and tell him he can have it all if he just fixes your screw-up.

We used to have a sign in the body shop where I worked at that read something along the lines of:

If we work on it from start to finish, our Rate is $25 hour.
If you work on it, mess it up, and need us to fix it: $35 hour
If you screw it up royally, and you need us to sort out the mess, restore it to fixeable and THEN fix it, $150 / hour.

P.S. BEG if necessary
 

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Going down the path to ruin.....

Sorry, but this has got to be one the the most often screwed up 'maintenance' items on the Z. EVER! Since, your dizzy is not lined up, and now that the tensioner is loose, your only real choice is to remove the front cover and realign EVERYTHING. This is well documented on this site and also very well laid out in the "How to Rebuild Your Datsun/Nissan OHC Engine" book. (See the Bookstore at left of page). The crank and cam need to be set at #1 TDC on compression stroke, the chain aligned correctly, AND the oil pump drive needs to be set correctly (that is what was out of line to begin with and caused your distributor to be out of alignment). If it is not all lined up correctly you will be forever trying to get the car to either start, or run correctly, and your dizzy will be way off and then you will be moving plug wires around to compensate. Take escanlon's advice and get a good mechanic to straighten it all out. Then when someone tells you that your Z jumped a tooth on the cam, tell them to take a hike. The only time I've seen a Z 'jump a tooth' was after someone tried to 'FIX' something and let the tensioner loose (sort of like what happened to you). Don't feel too bad, you're not the first one to have this happen. Good luck on the repairs.
 

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Re: Going down the path to ruin.....

The timing chain and valve timing have nothing to do with the ignition timing.
 

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Re: Going down the path to ruin.....

Except it invariably gets messed up as a result of changing the cam timing, because the oil pump gear (distributor reference) gets taken out when the front cover comes off.

Correct.

So get the valve timing right, insert the dizzy drive right, then the ignition timing is easy.
 

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Test... n/c

< a href ="http://www.thewoodlandscarclub.com/misc/scott01.mpg">http://www.thewoodlandscarclub.com/misc/scott01.mpg</a>
 
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