I have a lot of questions to fit into this thread so will try to do this is some sensible order. From a previous thread we concluded that the most likely diagnosis for my rattling noise was the good old VTC rattles. I pulled everything off the front of the engine and Matt (Zedboy) was good enough to drop over some good second hand cam gears. Now I''l put my question s in order of disassembly..... When removing the harmonic balancer I was aggressively jiggling it around trying to get it off when it came loose and slipped through my hands, landing on the concrete floor. This is the result: The outer edge got chipped, but also I was able to see that the inner shaft was also damaged. I think this was already present. QUESTION 1: Do I throw this in the bin? QUESTION 2: Another member has offered to sell me his harmonic balancer, but it's off an NA (mine is TT). I know they have a different number of ribs for the PS belt, is there any other problem with using an NA harmonic balancer? QUESTION 3: If I use and NA HB, can I just use a NA PS belt and it will work? When the harmonic balancer finally surrendered to my persistent agressive jiggling, it came off in a bit of a hurry and the only thing that I can see fell out was this: I cant believe that this little piece of beat up metal is responsible for holding that pulley in place . Am I missing something or is that just how it is?? (on a side note.....how good are phone camera's these days!!) And finally......now that I've replace the cam gears I cant seem to notice any real difference between the "new" ones and the old ones. Car is not back together yet but comparing the 2 sets of gears provided me with no real sign of failure in the old set. QUESTION 4: Should worn out cam gears show visual evidence of wear? QUESTION 5: Does this mean I should be looking else where for a rattle???? Thanks for any advice in advance
That little piece ...... of "beat up metal" is commonly called a Woodruff Key. It provides the turning force on the harmonic balancer, it doesn't hold the harmonic balancer on, the bolt in the end of the crankshaft does that. The key should be a precision fit in the crankshaft & have minimal clearance on the keyway in the harmonic balancer. Going on your picture, it is probable both keyways in the crankshaft & the harmonic balancer could be damaged. The key is junk, & whoever installed it should be horse whipped.
Noisy gears are the result of damage to the internal gears in the VTC sprocket. Normally a result of fitting heavier valve springs... Are you sure the noise was on the front of the motor?
Are these readily available? Where should I get one CZP...Nissan? Edit: Ah so this is what it c should look like ... http://www.conceptzperformance.com/Cart/description.php?II=2309&Car_Type=NIS300&UID=20130905010421122.106.251.244
Sounded high up (under plenum or at front).....as much as I could tell. Matt had a listen and also said it sounded like it. Of course that doesn't mean it cant be something else that just sounds like it though.
Get a cheap stethoscope from supercheap or similar. Makes it much easier to locate and identify noises.
Afaik the tt and na balancers as the same except for the 3pk/4pk variation in the power steering groove section. You 'can' use a 3pk belt on the tt ps pump, however if you have hicas active i wouldnt recommend it due to the pump needing the extra driving force.
Noises Having witnessed the standard of workmanship on the harmonic balancer key, it doesn't exactly fill one with confidence concerning any other components that may have been previously "repaired, replaced or adjusted". Shane's suggestion concerning the stethoscope would be a good starting point.
Think your balancer will be OK to reuse. That edge busted off the power steering drive isn't that important. Get a file and round it off and sand it smooth. It will be fine. The woodruff key is a long way inside the groove. I doubt the little bit busted off will matter much. Just check the groove further along doesn't look hammered. Also check the crank shaft keyway for damage. Do however get a new woodruff key though. Local engineering supply place or bearing company will have a new one. Lots of balancers have a pce missing out the pulley edge cause people try to remove it with a puller on that edge and it breaks straight off.
Further to Rob's earlier comment I found this informative piece on wiki:http://z32.wikispaces.com/Variable+Timing+Control Shows the internals of the cam gears.
Wooow.... That's a really coool picture of your thumb, how many mini pencils is your phone camererara...??
Update.....not CAM gears !!! It's taken a while to get this job done as opportunities to work on the car seem to be hard to come by. As a quick summary.........I managed to change the cam gears and get the car back together eventually. Went to start for the first time (a bit of anxiety building over the possibility of stuffing up the timing belt re-fit), turned the key and didn't get even a dash light (anticlimax.....). So now just replaced the battery and she has happily jumped to life with the first turn of the key. So that's the good news. the bad news is the noise that initiated all of this work is still there . So anyone got any new ideas???? Sounds like the VTC rattles but isn't.
video it with that camphone of your and let us hear it could be lifters, normal ignition noise, pinging, cam bearings, piston slap.. lots of mechanical noise (normal and not)
A-Briz-Z it's a wonder I didn't notice this the other day. In the photo of the harmonic balancer it looks like the rubber is cracked ?. I had a commodore years ago that was making weird arse noises. I first replaced the idler pulley because it was a rattling type noise. After being sent to a power steering expert for what one mechanic said was a power steering pump noise. The power steering guy walks out and listens then tells me it's the harmonic balancer beginning to let go. Apparently the resilient rubber that joins the crank part to the belt part sometimes lets go. A new harmonic balancer got rid of my noise . Have a good look at yours because it does look cracked in that photo. Cheers Dave
Thanks Dave, but I actually dropped this one so replaced it with a good one....at least that rules one more thing out
Yeap I've done one previously but it wasn't great so I'll do it again. Definitely not a "normal" sound. It's sounds like it coming from the plenum (below it I guess), and it's not a tinny rattle, more of a solid metal clacking that comes on with revs and is silent at idle. I'll find some time tomorrow to take another vid and post it up.
