A while back I posted a video of my forged rebuild clattering. I was unable to find help here, but a friend suggestes I get a stethescope. The sound was definately comin from the timing case. I tore it apart and found the chain had been riding on the inside of the guides, and wasnt touching one particular guide ("tension guide" by the water pump) at all. Because of this it was slapping and tore off some teeth from my water pump. What would cause the chain to off track? Any ideas?

 

Do you have pics?

What exactly was required to fix it? New tensioner?

I remember seeing your video, my motor has a similar issue.

 

I do not have any pictures on me right now. But if you like, I can take some when I get home from work.

I took apart the time in case. I was able to do this with the engine in the car. the slim fans helped. I am going to require new guides, new water pump for sure. I think I am just going to get a new chain and tensioner as well. I am looking for advice on how to stop it from happening again.

symptoms included: occasional overheating especially at idle, and a slight ticking noise which could be heard at its loudest when the stethoscope was placed on the timing gear rocker cover on the drivers side.

How does that compare to what your z is doing?

 

Hmmm...

My car is tempermental and fawks me over whenever possible. I had just dyno'd it for $hits and giggles to ensure it was making the same power. It was. Drive it home 45 mins, did a few pulls thru 4th nothing crazy. All seemed well.

I get near home and hear a tick, tick, tick going up with rpm's, but only when next to a wall. Get home, pop the hood car is running, sounds really rackety. I dont have a loud motor like some built guys, to me it sounded like the start to rod knock like I had in my old car. At other times it sounds like its in the heads to me.

But then the sound went away after maybe 10 minutes of idling, so it cant be rod knock. It comes and goes, but mostly its around and rpm dependent. At 2200rpm's its loudest. I touch the timing chain cover and cant positively tell something is slapping it. I remember your post and then a few other guys had this timing chain tensioner crapping out issue and Im thinking maybe its that. I spin the motor to 8000rpm's occasionally now Im wishing I hadnt!

Im stumped. Havent driven it since December when it happened, and to be honest I miss the $hit out of it but havent had time to mess with it.

 

Man. Get a stethoscope. They are real helpful. You can really pinpoint the sound.

Weird it sounds like its coming from the block sometimes and from the heads at others... Does it happen cold but go away when it warms up?

 

First guess would be a failed tensioner. Check the teeth on all gears for wear. Good find btw. Could have easily ended in disaster.

 

Jiggy, im glad I tore it back down, that's for sure. I have spare timing components, but I think ill just get new guides and tensioner. ,may as well get a chain too. What's another 100 bucks in the face of the 12000 I've already got into it? Its only money... Then ill take a good look at the affected gears. Thanks alot for that suggestion.

 

Change your oil and filter as well and you may want to pull the lower pan to make sure there aren't any metal pieces floating around.

 

Cass: the lower oil pan has to come off to get the timing cover off. Didnt see anything. Hopefull its in the filter

 

If it's in the oil filter, it had to go through the oil pump. That doesn't sound good.

 

I had the same issue on an 04 maxima. I changed the tensioner and guides and everything was all good after that. Check the chain over and make sure it isn't worn(chains rarely wear on these cars).

 

I had a loud tapping/knock when Ashley went to start the 350z this morning.

from everything I have read, it seems to be either an oil level/type issue or timing chain retainer.


I'll take a look at it when I get home from work and am not in a suit

Alberto,

Give me a buzz if you can to troubleshoot. I will probably take a short HD vid as well. The car has never made a single noise, so this isnt any type of progressive wear. It had been sitting for 60 hours as it usually does over the weekend.

512-757-2640

Thanks, Davis

 

Interested in hearing your findings. Mine did this same thing this morning. Loud clacking at crank up, and then softening to a tap. Car doesn't do it when it is warm. I don't know what to think???

 

^ its just the tensioner losing oil pressure before start. Its just an annoying noise, no wear issues. my built engine does it as well.

 

ours is a pretty noticeable tap, even from inside the car.

The sound is most noticeable from the actual plenum near the rear. This let me to believe it was more an issue with the cam/lifter/bucket on the passenger side rear cylinder.


where does the sound normally originate from?

 

I bought my 04 350z with 102,000 miles. The guy has 4 z's and told me after 100,000 miles with this year the timing chain guides on the first two chains will need to be replaced because there made of plasic and the new ones out are made better. It did start making the knocking noise at start up for 2 seconds then goes away like he said I'd hear. The oil gauge sending unit is bad as well I believe. When you put the key in on acc it jumps to 120 and stays there! Sending unit sensor is bad from what I have been reading. I no The oil pan has to come off to change the chain guides. Would it be easier just to take the engine out to replace the guides on the chains? Any other advise anyone can give I am open to! This is my first Nissan. I want my car to run forever and want to get these issues taken care of asap!! Please help

 

I bought my 04 350z with 102,000 miles. The guy has 4 z's and told me after 100,000 miles with this year the timing chain guides on the first two chains will need to be replaced because there made of plasic and the new ones out are made better. It did start making the knocking noise at start up for 2 seconds then goes away like he said I'd hear. The oil gauge sending unit is bad as well I believe. When you put the key in on acc it jumps to 120 and stays there! Sending unit sensor is bad from what I have been reading. I no The oil pan has to come off to change the chain guides. Would it be easier just to take the engine out to replace the guides on the chains? Any other advise anyone can give I am open to! This is my first Nissan. I want my car to run forever and want to get these issues taken care of asap!! Please help

 

Any updates? I think I need to do this also. Would I be able to do the timing chain guides and tensioner with the motor in my car at home? The local z mechanic wants ~$1700 to do this.