Replaced Tensioner and Water Pump. Concerned about Timing

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Legend11
Posts: 51
Joined: Thu Jul 24, 2014 11:36 pm
Car: My Car: 2001.0 Infiniti QX4
Dad's Car: 2001.5 Infiniti QX4

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I just recently changed my timing chain tensioner because of a rattle on cold starts (the guide was not broken, so I'm hopeful it was a bad tensioner.While I was at it, I thought it would also be a good idea to replace the water pump since I had everything apart.

Here are the steps I took so far...
1) Rotate the engine clock-wise to set top dead center for good measure (I'm not 100% sure I did this right, but I matched the crank pulley single line to the the water pump pointer)
2) Removed the old timing tensioner
3) Rotated the engine counter clock-wise for slack in the water pump (Service Manual says 20 degrees, but I was paranoid of having the teeth skip so I probably got it to work at 17-20 because it was a little tight)
4) Replace waterpump and then installed new timing tensioner with pin intact. Tighten down all bolts
5) Rotate engine clock-wise to remove slack and then remove new tensioner stop pin.

At this point I felt confident and decided to manually rotate the engine a few times clock-wise to review mechanical, but I'm concerned about something! I noticed every rotation or so, the tensioner would compress and then complete decompress!! Is this normal behaviour for air being in the system? Also I do have my spark plugs removed because I am changing them as well. Is this what's causing the tensioner to decompress?

I'm scared to death to finish putting everything back together only to start my truck and I'm fearing the worst. Anything I can check besides pulling the timing chain cover and oil pan off to review everything. I'm really concerned about the tensioner decompressing and then compressing after every rotation. Just not sure if this is normal considering I just replaced it and there wasn't spark plugs. Just wanted to get some opinions before I try to finish the job.

I appreciate any advice before I continue on. By the way, my truck is a 2001 QX4


Legend11
Posts: 51
Joined: Thu Jul 24, 2014 11:36 pm
Car: My Car: 2001.0 Infiniti QX4
Dad's Car: 2001.5 Infiniti QX4

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FYI, the timing was right. Besides my stomach sinking when I turned the key, the truck started up without any problems. Thanks

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rgk
Posts: 587
Joined: Tue Dec 23, 2014 4:48 am
Car: 02 Pathfinder LE 3.5 auto 4x4
Location: Indiana Dunes National Park

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Did the new tensioner fix the rattle?

Legend11
Posts: 51
Joined: Thu Jul 24, 2014 11:36 pm
Car: My Car: 2001.0 Infiniti QX4
Dad's Car: 2001.5 Infiniti QX4

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in case anyone else finds this thread helpful, I will post my private message response to RGK: (as of today, 9/14/2019)

"No, it did not have any change. To be honest, the truck as done this since I've owned it (purchased July 2014) and goes away after a few seconds on a cold-startup (first start of the day). I've noticed that if I start up the truck multiple times throughout the day it does not do it. I have put on around 46,000 miles on it and still continues to run without issues.

My truck also burns oil and has done this since I purchased it (possibly why it was dumped to a used car dealer to begin with). I have learned to live with it and I keep a close eye on the oil levels, top it off, and change it every 3-4000 miles.

Good luck."

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rgk
Posts: 587
Joined: Tue Dec 23, 2014 4:48 am
Car: 02 Pathfinder LE 3.5 auto 4x4
Location: Indiana Dunes National Park

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I also had a cold start rattle and oil burn. One day I hooked up an oil pressure gauge, and was dismayed to find that my oil pressure did not go up until the rattle went away. What's worse, the pressure at idle was about 5 psi. Specifications say that it should be at least 15 psi. Bless your heart if you ever have to go through the hell that is unscrewing the oil pressure gauge on a 2002 Pathfinder.

I tore into the engine and found three broken pistons, which would account for the oil burn. The bearings were in awful condition, explaining the low oil pressure. The left secondary tensioner would collapse with just a bit of downward finger pressure, and because of this the chain had a bit of slack in it. I believe all of this can be attributed to low oil pressure.


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