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72 z distributor way out of range


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I am having an issue with my distributor's adjustment range it's a 72 Z manual trans. Basically everything is lined up, #1 TDC(verified with lobe face up and to the right), zero on the crank, 11:25 at the shaft, rotor to number 1 but my dist is way out of the range of the lock nut. Someone suggested the distributor could be different, which is a great possibility(not the original owner) but looking at photos online it looks like my pedestal installed is correct and the 74 Z is electronic I believe.

 

attached are some pics.

 

Thank you for your time and happy new year!!

 

 

post-26460-0-95124100-1483249378_thumb.jpg

post-26460-0-51885200-1483249385_thumb.jpg

Edited by hatepotholez
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The first pics were of the distributor position when the car was running.

 

Here's some more pics. I just took these and haven't verified if the distributor is the original.

Is that first pic at TDC?  That is definitely not 11:25...

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ok tdc pics.

Okay, first off, it looks like you might be off one tooth on the drive spindle.  Here are pics from two different service manuals depicting the "11:25" position...

Dist Drive

Lseries 11 25

In your pic, the spindle seems to be aligned slightly counter-clockwise in relation to a straight line drawn through the two mounting bolts.  In the FSM pics it's oriented about that same amount clockwise.

 

Secondly, the cam timing looks funny, assuming it's also at TDC.  It looks like you have the first cam lobe pointing straight up - normally the first and second lobes (#1 exhaust and intake) are about evenly spaced on either side of "straight up" at TDC on the compression stroke...

 

EDIT:  sorry I had that backwards - it looks like the 2nd cam lobe is straight up, not the 1st.

Edited by TimZ
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I agree with TimZ, if that is TDC #1 on compression stroke, then your pump and cam timing are funny.

Double check that you are at TDC #1

 

Are we talking about the same distributor all along here, the D612-53? If so, how was it secured before? Didn't get the electronic dist. reference.

 

Keep in mind that these are old cars, mods may have been made.

 

If my memory were better I might be of more help, as I ran into this when converting mine to electronic and I suspect that there might be a little oddness here with the D612-53 (rather than the 52,54). Perhaps someone who knows this stuff will happen along, otherwise I suggest googling your distributor and reading all you can. There are a few posts on other forums related to this.

Michael

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I agree with TimZ, if that is TDC #1 on compression stroke, then your pump and cam timing are funny.

Double check that you are at TDC #1

 

Are we talking about the same distributor all along here, the D612-53? If so, how was it secured before? Didn't get the electronic dist. reference.

 

Keep in mind that these are old cars, mods may have been made.

 

If my memory were better I might be of more help, as I ran into this when converting mine to electronic and I suspect that there might be a little oddness here with the D612-53 (rather than the 52,54). Perhaps someone who knows this stuff will happen along, otherwise I suggest googling your distributor and reading all you can. There are a few posts on other forums related to this.

Michael

 

Yup, D612-53. It was always out of adjustment. No electronics here. 

 

I know it's an emission distributor per the FSM. 

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I don't think your at tdc on the compression stroke.

I would suggest ignoring the distributor, and front of the engine.

Pull all the plugs, plug #1 with your finger and crank it around until you feel pressure, then with a flashlight, and something non-marking, and combustable like a bamboo skewer, get the number one piston to the top of its stroke. #1 exhaust and intake valves will both be closed (or no pressure), and both lobes pointing up, ie 180deg from the contact with the rockers, which should both be loose (ie .006-.008 or so). Now see if your cam timing marks line up, and see what the top of the oil pump/dist drive looks like, and look at the front harmonic damper pulley to see if it has any marks that might be useful in the future.

 

If your dist drive looks exactly like the manual pictures, your distributor should fit. If not then you need to pull and reinstall the oil pump.

Michael

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I don't think your at tdc on the compression stroke.

I would suggest ignoring the distributor, and front of the engine.

Pull all the plugs, plug #1 with your finger and crank it around until you feel pressure, then with a flashlight, and something non-marking, and combustable like a bamboo skewer, get the number one piston to the top of its stroke. #1 exhaust and intake valves will both be closed (or no pressure), and both lobes pointing up, ie 180deg from the contact with the rockers, which should both be loose (ie .006-.008 or so). Now see if your cam timing marks line up, and see what the top of the oil pump/dist drive looks like, and look at the front harmonic damper pulley to see if it has any marks that might be useful in the future.

 

If your dist drive looks exactly like the manual pictures, your distributor should fit. If not then you need to pull and reinstall the oil pump.

Michael

 

Note:  Crank the engine over _BY HAND_ to try to find true TDC.  Also the method above will get you close, but it's pretty difficult to find dead nuts TDC this way, since the piston doesn't move much vertically +/- 10 degrees from TDC.  Go get a piston stop:

http://www.oreillyauto.com/site/c/detail/PRF0/66792/N0869.oap?ck=Search_N0869_-1_-1&pt=N0869&ppt=C0150

 

...and do it right.  from your pics assuming you lined up TDC with the crank pulley and it wasn't wrong, it looks like you are of by a tooth on both the distributor and cam timing.  Of course this could also be a problem with the crank pulley having slipped.

 

So - find true TDC, verify your crank pulley timing mark, and then verify the distributor and cam timing.

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I don't think your at tdc on the compression stroke.

I would suggest ignoring the distributor, and front of the engine.

Pull all the plugs, plug #1 with your finger and crank it around until you feel pressure, then with a flashlight, and something non-marking, and combustable like a bamboo skewer, get the number one piston to the top of its stroke. #1 exhaust and intake valves will both be closed (or no pressure), and both lobes pointing up, ie 180deg from the contact with the rockers, which should both be loose (ie .006-.008 or so). Now see if your cam timing marks line up, and see what the top of the oil pump/dist drive looks like, and look at the front harmonic damper pulley to see if it has any marks that might be useful in the future.

 

If your dist drive looks exactly like the manual pictures, your distributor should fit. If not then you need to pull and reinstall the oil pump.

Michael

 

Ok, I will try this.

Note:  Crank the engine over _BY HAND_ to try to find true TDC.  Also the method above will get you close, but it's pretty difficult to find dead nuts TDC this way, since the piston doesn't move much vertically +/- 10 degrees from TDC.  Go get a piston stop:

http://www.oreillyauto.com/site/c/detail/PRF0/66792/N0869.oap?ck=Search_N0869_-1_-1&pt=N0869&ppt=C0150

 

...and do it right.  from your pics assuming you lined up TDC with the crank pulley and it wasn't wrong, it looks like you are of by a tooth on both the distributor and cam timing.  Of course this could also be a problem with the crank pulley having slipped.

 

So - find true TDC, verify your crank pulley timing mark, and then verify the distributor and cam timing.

 

lol funny you mentioned this. I was actually at Advance auto trying to get a piston stop which they didn't have. I instead will have my job bore out a 240z spark plug and insert a dial indicator, that should give me the absolute TDC and then go from there. 

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Ok some great progress today. I used a dial gauge(like a piston stop) inserted into cyl 1 spark plug hole to find absolute TDC. This worked great. But even before this I tried looking for the notch and groove on the cam plate and cam gear, no luck maybe I didn't look hard enough. Anyway it was cold so I continued, I got TDC on cyl 1, using the gauge on the compression stroke, the cam lobes were in the V orientation. I looked down on my damper and it was no where near 0 TDC, more like 50 degrees. I knew the issue right away, my damper was twisted at some point. So I used a white ink pen and made a mark to locate the new TDC mark. I also saw my distributor tang was at 12 not 11:25. Went on to the distributor locked it down and tried to start it, had to play with the distributor a little bit and then it ran. I was able to set the distributor where there was no backfiring and the engine revved easily. I then used the timing light which is useless as my damper has incorrect measurements. I noticed the timing was maybe at 10-15 degrees, this is a very rough estimate.  As of now i'm done with the timing, I will have to one weekend thoroughly go over the timing. I'll look for the notch and groove, check to see at what pin my cam gear was installed on, check crank to cam timing,  drop the oil pump and realign the distributor drive, install a new damper.


 


The next is to tackle the carbs, I readjusted the front float and the car was less rich than before. I tried looking for some clear hoses to check my float levels(thanks Peter for this suggestion and the multiple other suggestion) but couldn't find any. But in the meantime I will buy some plastic tubing and try to make some float level gauges from the bowl drain bolts. This float issue are a real pain in the arse, I'm done trying to bend them this way and that way to get it straight. I know for sure the front carb has more gas in the bowl as compared to the rear per the WD-40 stick per @siteunseen(thanks!) I'm going to buy some new ones and call it a day. My carbs btw are almost synced as I used my uni-syn to check between them so once I fix the float levels and some minor adjustments they should be good to go.


 

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I knew the issue right away, my damper was twisted at some point. So I used a white ink pen and made a mark to locate the new TDC mark.

This is fine as a temporary test to see if everything else is working, but this is indicating that the elastomer in your damper is failing, so it will likely slip again, or even worse come apart.  

 

Probably time for a new damper, or get your old one reconditioned - TonyD mentions a place that can do this here:

http://forums.hybridz.org/topic/117357-damperpulley/?hl=%2Bdamper+%2Brecondition&do=findComment&comment=1100309

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This is fine as a temporary test to see if everything else is working, but this is indicating that the elastomer in your damper is failing, so it will likely slip again, or even worse come apart.  

 

Probably time for a new damper, or get your old one reconditioned - TonyD mentions a place that can do this here:

http://forums.hybridz.org/topic/117357-damperpulley/?hl=%2Bdamper+%2Brecondition&do=findComment&comment=1100309

 

Thanks for the link. Any other dampers to look at that is a direct replacement instead of the rebuild?

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re dampers:

Performance Products makes a couple aftermarket ones, a stockish one, and a sfi spec 'racing' one, for a little over a bill or two, repectively. If your really going racing there is the BJH/Rebello damper, at roughly 5 bills.

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