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Old 01-07-2021, 08:26 PM   #11
essaysee
 
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crank shaft at second notch, screwdriver at highest position. .... valves look to be closed though... I guess my thoughts were off. Don't mind that the distributor is 180 out, I've been rather successful with installing that. I'm still not getting compression however.

I guess this evening I am working on a leak down test.

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I'm not sure if there's a better method to upload directly to infamous nissan
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Old 01-07-2021, 10:19 PM   #12
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To me it appears that the camshaft is rotated clockwise too much. Possibly enough to allow valves to remain open when they should be closed. I would recommend removing the timing chain and realigning the bright links on the chain with the dimples on the sprockets.
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Old 01-07-2021, 11:35 PM   #13
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Thanks Alabama,
I've tested cylinders 1 and 2 so far on the leak down. I don't have a gauge attached to it addition to measure the percentage drop, but cylinders 1 and 2 I am getting noise coming out of the timing chain well (further down, oil pan back up again to cylinder rings). I believe I am interpreting that right.

++++++++++++++++++++++++++++++++++++++++++++
Should I stop everything now and realign bright chain links, or is the leak down sufficient in proving the valves are actually closing at the right time?
++++++++++++++++++++++++++++++++++++++++++++

At TDC I didn't have leaks to exhaust or intake, which I believe is good... but it might also mean that I've destroyed my piston rings on all my drystart attempts...

which means I gotta take the head off... drop the oil pan, take the cylinders out from the top... (I really don't want to drop out my crank shaft).

Am I thinking this through logically?
Also, if it is ending up to be piston rings (100$ rock auto), do you think the risk/reward is worth it... or just abandon.

I know it's my decision and your opinion.. I am just wondering if I'm going to be wrenching on this until 2022...
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Old 01-07-2021, 11:41 PM   #14
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I’d do the timing chain before I did anything else. Once we KNOW that’s right then we can move forward. I wouldn’t make ANY decision until that’s done
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Old 01-07-2021, 11:41 PM   #15
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Quote:
Originally Posted by alabama_lowlife View Post
To me it appears that the camshaft is rotated clockwise too much. Possibly enough to allow valves to remain open when they should be closed. I would recommend removing the timing chain and realigning the bright links on the chain with the dimples on the sprockets.
I believe that takes 17 full rotations of cam shaft before they will line up ( https://youtu.be/WJXI9-khTaA?t=272 ) ... or do I not understand how that works. If it's not aligned, and needs to be, that surely could be my problem and I jumped a few teeth however, piston being TDC, I would think I would get air leakage out exhaust or intake if the valves were coming down too soon and letting out compression.

As a sanity check, I hand cranked the truck to make sure I would recognize a noise difference in air coming out of exhaust (you can feel on tailpipe) vs intake (high whistle) vs piston ring/head gasket (sounds like low tone steady hot oral exhale "HAAA")
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Old 01-07-2021, 11:57 PM   #16
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I might be the luckiest sonova ...I went out there and the blue link lines up with the dimple.

When I replaced my timing chain and tensioners maybe 3 years back, I believe I bought the whole kit and the 'special' link was blue. That's my memory at least.

Pictures uploaded.
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Since my right side chain tensioner was shattered however, that doesn't necessarily mean I didn't jump teeth...I just might have jumped on the crank sprocket instead of the cam sprocket

It would seem odd that all piston rings are shot, but this is a 96 with 240,000 miles and I tried to drystart it quite a few times (noob)
Leak down test gave me all the same results, air coming out of timing chain chamber (oil pan (cylinder heads))

Last edited by essaysee; 01-08-2021 at 12:27 AM.
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Old 01-08-2021, 12:27 AM   #17
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One of the links being aligned with one of the dots doesn’t tell us anything. You need to see both ends. The chain links which are a different color are only important ONE time, that’s when you install them. Any time after that initial installation is not relevant. There are 2 colored links and 2 dimples. Both must align when the chain is installed. With the timing cover installed you can’t see if the bottom dimple and link are aligned.

Set the engine to TDC on the compression stroke of the #1 cylinder. Remove the timing cover. Remove the chain and align the bright links with the dots. If they’re not aligned, rotate the camshaft, not the crankshaft.
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