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Discussion Starter #1
Okay, if you recall have had this car running, no real power on the highway, started with the choke okay, took out the gas tank, installed a pertronix kit, put everything back together, car is a bear to start. It will run with a **** of a lot of messing with the choke and retarding the spark to get it started, but it is rough and backfiring all the while. It did smooth out to an idle after it warmed up, but bogged when you gave it gas.

I pulled the #1 plug, found tdc, pulled the valve cover and did like the archives said. It looks like my marks at the cam tower are off by an 1/8" or so, and my rotor is pointing barely halfway between the #4 and the #1 lead, closer to #4. This with the distributor timing marks at zero.

I am guessing that my distributor is off a notch. Could it be my chain is off a tooth?

I read that the oil pump is connected to the dizzy, but can't find it in the CD manual.

Any help would be greatly appreciated. I will NOT touch the cam sprocket until I hear from someone. If that is the problem, explain the wood wedge trick.

Peter
 

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Good idea. First check the chain. Now, on a factory or dealership install they might put the chain on without using the "bright" links to line up with the sprocket. They have some other method of measureing where the chain goes. (certain number of links between a mark on the top sprocket and the bottom) The point is, your bright link may not line up with the mark on the sprocket but it "could" still be ok for the cam timing.

But anyway, rotate the engine some more. You may have to around four(?) times max before the bright link lines up with the #1 on the sprocket again. It does not line up on EVERY rotation.Do this untill you seeit line up. If it does, then you're ok with the chain. If it does not line up, then the chain may or may not be put on properly.

The oil pump slides in from the bottom and then you slide the distributor down and match it into the slot on the top of the oil pump shaft. This lineup is very important.

I have messed up on this once on my 280Z. I was advanced on my ignition by about 20 degrees. My engine ran so I didn't know it was wrong at first. I had a very responsive throttle feel but it would suddenly die sometimes if I let it idle lower than 900 rpm. I had to re-insert the pump to fit the problem.

If you have a timing light, use that to see how close your ignition is. Be sure to use some white paint or "white-out" on the pully mark or you won't really be able to see the mark that well. If you can't see it at all after trying a few times, you are probably + or - by 18 degrees or more.

I also used the block of wood trick before. I still have the piece. You cut the wood to a certain size. Then you take off the valve cover and slide the stick down between the chain where they come close together. Smack it down a few times with a hammer. make it tight, but not so tight that you'll never get it out again! (drill a hole in one end of the wedge so you can put a wire through it and use that to pull up on afterwards.

You can then remove the sprocket off teh end of the cam, and the chain will not fall down off the lower sprocket or let the chain tensioner push out any more. I even pulled the head at that point to fix a valve and put it back on with no problems! I was kinda nervous though. I hate having to pull the whole front cover off and put that stupid oil pump back in!!!
 

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L series chains don't skip teeth,if it did you'd be hard pressed to not recognize it(ie seized motor from valve to piston interference)The ditributor only goes in to the base two ways,correct or 180 degrees off.More than likely someone had the distributor shaft and oil pump out and got the timming marks off slightly on reasembly.Set motor on TDC #1 remove the oil pump,re aligne the timming marks and reinsert without changing this relationship.If this sounds like a pain in the ass your right but if you want your distributor to be in the center of its adjustment on the tower that's how you get it there.
 

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Discussion Starter #4
Thanks for the reply; just came back in after pulling the distrib body up, and took a look at the notch. There are only two ways the rotor can fit at this end. What you're saying is that if I pull the oil pump, and remove and reinstall the shaft, I can move it a notch or so to get my rotor lined up?

Peter
 

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Discussion Starter #5
Thanks jason and bleachz
I'm on it. The weather is cooperating, no time like the present. The job doesn't sound too bad, as long as I know I am on the right track. Your advice is appreciated.

Peter
 

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Discussion Starter #6
so I'm guessing that just dropping the pump half an inch, turning the rotor, and pushing the pump back up is not the way to go?

Peter
 

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The valve timing and ignition timing are unrelated. To check the distributor drive shaft set the engine with number one cylinder at TDC. (Piston at TDC both valves closed).

Remove the distributor.
Look at the drive shaft. The slot should be at the 11:25 O'clock position with the smaller half moon forward. If it is off the shaft was installed incorrectly and will have to be re-indexed by removing the oil pump.

The other thing that can happen is for the distributor drive gear to be installed backward on the crankshaft. If this is the case you will never be able to index the distributor shaft at the 11:25 position.

The reason that the valve timing and ignition timing are unrelated is because they are driven independent of each other off of the crankshaft.
 

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Discussion Starter #8
duh!?!

Well, thanks for all the advice; I pulled and replaced the oil pump and dizzy shaft, checking and re-checking the shaft orientation, only to find that I must have been looking at the wrong plug lead. The rotor is dead on #5, not #1.

Of course, I buttoned up everything, including the sway bar. BUT, I think I can lower the whole assembly enough to re-adjust without pulling the whole thing. It has been a good lesson so far, although the weather is cooling. Better get moving.

Peter
 
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