timing belt q's

[pathmaker1]

ok well a couple weeks ago just driving around town my pathy started making some horrible noises from the motor. it sounds kinda like valves smacking the piston or bad lifters but from the wrong area. also the "taping/knocking" only occures at idle(800rpm's). as soon as i rev the engine a bit the noise goes away. however when i let off the gas only after reving it the knocking turns into a constant rumble and sounds like bad bearings in a pulley untill it returns to idle and is a constant tick tick tick(a hell of a lot louder than noisy lifters BTW). i have no change in performance or gas mileage. i have come to the conclusion it is the tbelt tensioner but havent confirmed that yet. if its not the tensioner then i think i spun a bearing on the crank. i have checked the lifters and they are all good. got everything dissasembled and basically the tic mark on the passenger side cam pulley does not line up with the tic mark on the back timing cover at TDC. the drivers side tic marks dont exactly line up but its pretty damn close. here are some pics.

passenger side cam pulley at TDC:
http://i145.photobucket.com/albums/r207/gmacsurfin/random%20truck%20pics/S6301803.jpg

Drivers side cam pulley at TDC:
http://i145.photobucket.com/albums/r207/gmacsurfin/random%20truck%20pics/S6301804.jpg

i see the tic mark on the crank pulley but have yet to locate the tic mark on the oil pump housing to see if it is lined up. according to the hanes manual it looks like it is in the right position but i wont know for sure untill i take the tbelt off to get a better look at it. i did start the truck with the tbelt cover off and the tensioner is wobbling all over the place making the belt wobble like a SOB. i think that the tensioner is making all the tap tap/rumbling noises im hearing at idle.

ok so my questions are: since the tic marks on the passenger side pully dont line up would that have caused damage to the valves(and if so how would i check w/o pulling the head)? is it possible that the tensioner going bad made the tbelt jump a couple teeth? if the tbelt did jump wouldnt it have affected the drivers side cam pulley alignment at TDC or is it possible to jump timing on only one pulley? why do i have 2 tic marks on each cam pulley and how do i know which one i should line up with the ones on the tbelt cover?

thanks for any and all help guys. tbelt tensioner will be in on tuesday so ill be puttin my junk back together then and hoping like hell this will eliminate the horrible noise or else ill be rebuilding the bottom end.

[Allen Cox]

need a pic of the crank pulley. I won't have internet much longer, hope I can see it before I loose it.

I'll have web back Wednesday or so.

[Bill Potter]

count the belt teeth between the three pully marks...then look in the hanes book.... it gives you the count. I will be home on Monday evening and can look it up for you.

[NissanNut]

That looks kinda normal. Count the teeth between the 3 pulleys. Thats the most important thing.

http://nissannut.com/maintenance/vg30e_timing_belt/crank_gear-lower_marks.JPG

[pathmaker1]

http://nissannut.com/maintenance/vg30e_timing_belt/crank_gear-lower_marks.JPG

ok well i just rechecked for a mark for the crank pulley on the oil pump housing and i cant find it anywhere. i cleaned up the area to bare metal and there is no identifiable mark looking even close to the one in the pic. i was thinkin the belt was in the way or something. i have located the mark on the crank pulley but not on the oil pump housing.

another thing i dont understand about counting the teeth. why am i doing this? is it to determine if i jumped timing? i dont see anything in the haynes manual about the # of teeth between pulleys. if you could look that up for me broncb2b that would be awesome. on another note one section of the tbelt between the pulleys is pretty loose compared to the other 2 sections and it seems to be at the same point on the belt no matter which pulleys it is between (normal?). belt looks in good shape IMO.

i did however just notice the "factory" marks on the cam pulleys and they actually both line up perfectly with the ones on the back tbelt cover so what the hell are the white tic marks on the cam pulleys for? if you look real close you can see the dimples on the cam pulleys in my pics right above the R3 and L3 marks on each pulley. ill put a dab of white-out on em tomorrow to further illustrate.

and if anyone has a FSM on there computer there willing to send me somehow i would greatly appreciate it. been looking for one for some time. oh and incase some of you dont know(or forgot) what i got its a 1992 pathy

[Bill Potter]

In my book it is in the section about changing the timing belt. Wish I could remember the counts. The little dimples in the covers are not exact...most belts also have marks to help you line them up. Look at your new belt it should have lines on it. FYI...You can be off a tooth and the motor will not kill itself...but it will not run well at all.

The white marks were added by someone I don't know what they were trying to mark with them.

[pathmaker1]

the truck has always run great. i just started getting a terrible knocking from the front bottom of the motor pretty much from the tbelt tensioner so i figure ill replace this crap and hope it gets rid of the noise. if not then i think i spun a bearing and that would just suck. with this terribly loud knocking i am not loosing any performance whatsoever...it runs as it has for the past 16 years but just recently with a very loud, annoying, and not so good metal smacking metal noise but only at idle.

i have read and reread the section in the haynes manual with no sucess about the # of teeth between the pulleys. it gives me belt deflection specs and tensioner specs but thats it. no rush on the count since im waiting untill tuesday for the tensioner to come in.

[NissanNut]

From FSM.

133 teeth

40 from cam to cam
43 from left hand cam to crank

Count how many teeth between the dimples. This will tell you if something has moved.

[pathmaker1]

hey thanks for that Barry. everything is good with the teeth counting which is some much needed good news. now if the morons at advanced would order the right tensioner i would be test driving her right about now.

so since i cannot find the dimple on the oil pump housing should i just make a mark to line up with the dimple on the crank pulley since i know i have not jumped timing? i have searched for a dimple for about 1 hour and cant find anything close to that. the new belt i have has lines on it for the cam pulleys and a directional arrow so as long as i dont move the crank and count the teeth after install i should be ok with these data points to make sure my timing will be correct, right?

also Barry(nissannut), do you have the FSM on your computer? if so would there be any way i could download it from you. i have been wanting one for quite some time and cant find em anywhere for the WD21's.

Thanks

[NissanNut]

If you put the the harmonic balancer on the TDC mark and the 2 cams near there mark. That is TDC. Note the balancer mark can be at the timing mark for 2 TDCs, but if the cams line up its the compression version.

When you put on a new belt or count the teeth and use the old. That is all you need. Dont worry about the crank one.

You an get Digital FSMs for 94+ from Nissan for $20. There is no wd21. Its part of the D21 FSM. Nissan just calls it a "Wagon".

http://www.nissan-techinfo.com

Or from here.

http://www.phatg20.net/component/option,com_remository/Itemid,2/func,select/id,31/

[dezurtrat]

ok well i just rechecked for a mark for the crank pulley on the oil pump housing and i cant find it anywhere. i cleaned up the area to bare metal and there is no identifiable mark looking even close to the one in the pic.

I had the same issue with my '02 Xterra when I did the timing belt. No mark on the housing to line up with. I had to mark it up real well before I took it apart once I had the camshaft pulleys lined up correctly.

[Ryan Gee]

The pully on the crank backwards? In this case the mark would be been on the backside.

[Ditchfinder]

I had no crank mark on housing either when i did mine I used a center punch and made my own my pulley did have the marks for the timing.