# timing chain rattle, upper tensioner to blame, or is it something more?



## SonsofWisdom (Mar 29, 2004)

Howdy folks, I've done some reading and I've done a lot of searching. I'm pretty sure the problem is just the upper chain tensioner...but...since y'all have played with these more than I have I'd like your opinion on the matter.

My girls 96 sentra with the GA16DE 1.6L engine has 107k miles. It has the following symptoms:

1. rattling at lower rpms, goes away when rpm's are increased (no tach so I guess about 15k -2k)
2. Get up and go slacks until rpm's go up, you can feel it...about the time the rattle stops the get up picks up
These next two happened literally over night...
3. at idle sputter, acting like it would die and did die once.
4. smoking from tail pipe with engine warmed up BUT only after idling for a while...once she drives it around it stops smoking.

Mechanic told her she will have to replace the chain but he said "I'm not too familiar with this car and when I had one like it a while back that was the problem...With these new cars I don't think it would mess up the engine as bad as the older cars if the chain broke” His Mitchell computer software is messing up so he couldn't look up the engine.

Well I was annoyed cause my exp. with Toyota (former technician) told me that timing chains don't go out with this low of mileage, tensioners do but not chains (unless you leave them untaught for too long) and I know that today’s engines have much tighter specs...i.e. if the chains pop or even stretches to much...it'll cause MORE damage than those older engines...if not the same amount...ANY WAY I decided to have a looksie hearsie with her car in which I verified all her complaints and symptoms.

Question #1
Any way I'm wondering if since the chain has slack would that cause the valve timing to change thus resulting in a hesitant idle, smoking at idle, and relieved smoking at higher rpm? I imagine it would. 

Also, according to my girl, it only recently started to hesitate and smoke. It has always had the reduced power at lower rpm and reduced rattle at higher rpm, it literally started missing and smoking one night, I happened to be following her that night and the night before home from work. 

So I'm wanting to inspect the upper chain tensioner...so it's getting a new one no matter what...why take the old off and put it back on right?

Somewhere in one of the ga16de threads I read that the b14 does not have upper chain guides? Or tensioner...can't recall and I can't find that thread again...so...question section TWO.

Question #2
Does the b14 (96 year model sentra) with the ga16de have upper chain guides? Does it have an upper chain tensioner? I think the post was made concerning the SR20 wich would explain the confusion...but I want to make sure before I tear into this.

I appreciate any help I can get on this..


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## wrench (Jan 31, 2007)

SonofWisdom, you do have an upper chain tensioner. I think there was a small guide originally from the factory, but replacement timing kits no longer use it. One component you also have mounted on the intake camshaft is a valve timing advance mechanism.

Back to the tensioner. It has limited travel. If the timing chains (you have two) and gears are worn to the point that your tensioner is maxed out, replacing the tensioner won't change anything.

You do have an interference engine. If the chain(s) break you will do damage to the pistons and valves. Not to say that's going to happen, just something to keep in mind.

Not sure about the smoking, but would lean towards valve seals on that one.


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## SonsofWisdom (Mar 29, 2004)

Thanks for the reply wrench, I don't think the tensioner is maxed out, I'm thinking the tensioner is shot and just not capable of keeping the tension. Oh well I guess I'll find out tonight when I look at it.

another update...the rattle goes away in the following gears at the following speeds...if anyone has an aftermarket tach then you could figure the rpms...I think it stops rattling around 2100 or 2200 to maybe 2400 to 2500 rpms

gear and mph that the rattle stopped...also noticed the car didn't fall on it's face after this gear/mph mating...before the shown mph the car would just lag...

gear mph
2nd 22mph
3rd 32mph
4th 44mph
5th 54-57 mph can't recall

My girl and I swapped cars today and I've only driven her car to my house and very slowly at that...I was trying to keep the rpm's down as much as I could just in case 

Guess I should go to Nissan and get that part tomorrow too...grrr..prolly have to order it and it's prolly on back order...*sigh...oh well...I do love my girl 

Anyone else have some thoughts?


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## SonsofWisdom (Mar 29, 2004)

anyone at all...I'll take the peanut gallary? All right guess not...well I'll post what I find after I open 'er up today.


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## SonsofWisdom (Mar 29, 2004)

well folks the upper tensioner prolly need replacing..but...the intermediate sprocket...has no teeth on it...WHOO HOO...

So now I've gone from just one part to changing every part that touches the chains including the chains...this seems a little unheard of to me...the chains look good...not pitting or wear..but the sprockets...HOLY CRAP...even the cam sprockets look worn...but not the chain.

Oh well it's all going to get replaced...I'll post pics of the entire process


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## wrench (Jan 31, 2007)

SonofWisdom, BOL. I just finished doing the same job. One thing I didn't fully expect was the cost of the components. $1100. However, I did replace all hoses, water pump (highly recommended) and multiple peripheral components. Also, don't forget new headbolts!


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## SonsofWisdom (Mar 29, 2004)

wrench said:


> SonofWisdom, BOL. I just finished doing the same job. One thing I didn't fully expect was the cost of the components. $1100. However, I did replace all hoses, water pump (highly recommended) and multiple peripheral components. Also, don't forget new headbolts!


I hate to say this...but I'm pretty sure you don't have to take the head off...I've read a post giving an update...several of the threads I've read giving how too's say you don't and from the looks of it the intermediate gear and chain should go through that slot in the head either by pulling them down or by taking the crank sprocket off and bringing it up that way...I'm fairly certain...but honestly I'm not that far quit yet because I did most of my parts ordering yesterday. I'll be posting a step by step or hosting it on my site and linking to it here...or something...I'm not sure I've seen a detailed parts list and step by step for this...haven't looked to hard either 

Did you buy each part seperate or get a kit/set? Did you buy through the dealership? If you were to buy each part seperatly...well...just the chain and sprockets you'd spend well over 500 easy.

For a timing chain set I'm only spending $202, and then only about 50-60 for rebuilt water pump and a new thermostate...all in all including gaskets and "pookey" (rtv silicon that is oil resistant) and water pump, belts I should come out under 400 for sure...possibly under 300 or around 300.

At autozone the upper tensioner by itself is 67+, the same part/manufacturer at Oreilly was 37...the list price is 57. I'm not one to buy cheap manufactured parts.

My "how too" post will include where I got the parts and prices.

All in all I'm getting
TIMING CHAIN SET -Oreilly- or -online source- $197-$202 
upper chain
lower chain
upper tensioner
lower tensioner
lower tensioner gasket
lower right guide
lower left guide
two new bolt for these
exhaust cam sprocket
idler (intermediate) sprocket
intermediate sprocket shaft
crank sprocket
oil seal

TIMING COVER KIT -Oreilly- $6 to $10 
orings
and something else...

Water Pump and gasket -Oreilly- $28 to $38.99
Thermostate and gasket -Oreilly- like $16 or 18...maybe less

Valve cover gasket kit -Oreilly- I forget...I think like $20
includes spark plug tube seals etc...

Only thing I might run into problems with is the intake came VTC sprocket...prolly get that from the dealership...eesh...now that might jump my parts price up to a grand or more  Don't know yet.


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## nastynissan (Jan 26, 2003)

Hope I can be of some help.....

A... You Dont HAVE TO pull the head , But it IS recommended... Getting the seal right betweent he Timing cover and the Head is "Tricky" to say the least...

B... You DO have to pull the oil pan as the Oil Pump is part of the Timiing Cover...

C... Doing this with the engine IN the car is a MAJOR PITA!

D.... What sort of HELL did this engine go through??? Ive got one currently at 250,000mi. That only recently had the tensioner replaced.. Ive had Several in the past with 150-200,ooo that had Little to No wear on the tensioners....Much less the Gears..

E... If you havnt got one already... Get a FSM, Haynes or such... Reading Posts and Threads only goes SO FAR....

F... I HOPE your an experienced Mechanic... This is NO job for the Shadetree....

And in ALL Honesty... This is a Good Time to Invest alittle extra and do all gaskets, seals, Belts, Tune-up stuff, Etc... Basically a rebuild without the Machine work and New Internals.. If Its solid otherwise, It more than likely be worth it in the Long run..

BTW***The Ga16de I have with 250k is in an 89 Pulsar... And UM.... It Goes GOOD!!!


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## wrench (Jan 31, 2007)

nastynissan summed it up very well. BTW, look at the sticky at the top of this forum. You can get a FSM through it.


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## SonsofWisdom (Mar 29, 2004)

Thanks for the replies!

As for that seal...I'll have to make that call once I get to it and depending on how long I have to d*ck with it...but I do appreciate the heads up!

Yeah I figured the oil pan would have to come off...all the 4cyl chain driven car engines I've seen are like that...nissan and toyota.

So far everything has had a hella lotta room...well compared to the last two cars I did head/chain work on; an 01 and 03 celica GTS...NO ROOM AT ALL!! oh my gosh those sucked. But I'm waiting to get that ONE bolt where even with the engine mounts off and the engine cocked to one side a bit it's still 3 cm too long...HA HA...haven't found it yet but I will  prolly the oil pump huh?

What kind of hell? I so wish I knew...107 and that int. sprocket is next to nothing...that is really worrying me. I told her at 50k after this fix I was checking it again. It's had at least 3 owners before my girl bought it...she got it from a lady that only had it 2 months...sounds fishy to me. I would have told her to not get it...but...they didn't ask or tell me about it till now...HA HA HA...now that it needs fixin'  I imagine they ran it without oil maybe...who knows...the upper tensioner is REALLY shot so I imagine that slack allowed the chain to play around and wore that outer idler gear...once I get to the crank sprocket I'll have a better idea...but your right...this is WAY too much wear for 107k! She's done her oil changes about ever 3k, but I can't speak for the other folks. She hasn't had it very long either though.

I've got the manual from the link in the sticky and it's set up really nicely...the tabs and menus can be clicked and takes you were you wanna go, my thanks to whoever set it up...my manual for my 240 isn't like that (pdf file too), it sucks. I pretty much used it to make sure I got all the right parts when I called for prices...other than that...it's pretty much cut and dry...takes a lot of time to do but not too bad (er yet that is)...well...if you've done them before and know how important organization is.

My creds are ASE cert master auto tech, associates degree of applied sciences in auto tech....T-TEN program, and toyota cert expert tech...
Yeah...unfortunately I know all to well how...uhm..."fun" this will be HA HA HA...eeehhhh...that's not really funny now that I think about it.

Well like I'd said up above, other than the head gasket, all the seals are getting replaced and I'm also putting in a new water pump too...pretty much if it comes off...a new one goes on.

See I'm really really worrying about why this engine is so worn...I was ok with the upper tensioner being the only worn item...but..I don't know...I'm hoping to find the rest of those teeth once I drop the oil pan...if they aren't there...expletives will fly...about like when I saw the intermediate sprocket  cause that means...I GET TO FIND THEM!!! and who know the damage there...I'm just glad this car didn't get driven anymore...I'm surprised it didn't jump time several times...scary...you'll get to see when I get those pics up


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## IanH (Feb 11, 2003)

SonsofWisdom said:


> gear mph
> 2nd 22mph
> 3rd 32mph
> 4th 44mph
> ...


22 mph is about 2400 rpm on my 97 sentra.


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## SonsofWisdom (Mar 29, 2004)

Thanks lanH...that's around what I figured.

Update...I haven't had time to so much as think about touching the car since...well my last post...sunday the 25

Parts might be in tomorrow...if not then saturday.

Bad news...only place I can get the intake cam sprocket is dealership...$511

Found an engine I could get off another 97...but he wan'ts 645 for the engine...I only need a 500 part (and that's new...not paying 600+ for used)

Another lead I will check out tomorrow, guy with a 96 "no good" engine. Says I can see if it has what I need. Not to optimistic...since the engine's no good...that's a very bad sign...plus it's older...most likely has higher mileage...and thus...equal or more wear.

Most likely going to have to buy that part from the dealership...I can't find it anywhere else is what really sucks...I don't want to put in a used one...that just doesn't make since...oh well.


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## nastynissan (Jan 26, 2003)

Ive got an intake sprocket or 2 laying around.... Used but in Good shape... PM me if interested..


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## IanH (Feb 11, 2003)

nastynissan said:


> Ive got an intake sprocket or 2 laying around.... Used but in Good shape... PM me if interested..


Are these with VTC for the 96 ?


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## nastynissan (Jan 26, 2003)

IanH said:


> Are these with VTC for the 96 ?


Yup... PM with your e-mail if interested... Im getting ready to make a list w/pics for the Classifieds... Should have a Good Bit of Stuff...


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## IanH (Feb 11, 2003)

nastynissan said:


> Yup... PM with your e-mail if interested... Im getting ready to make a list w/pics for the Classifieds... Should have a Good Bit of Stuff...


I was checking for "sonsofwisdom" that this was the correct part.
however I need both lower control arms suitable for rebuilding....


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## SonsofWisdom (Mar 29, 2004)

Well folks I was able to do 1/4 days work last night and night before. All I need to do is put the belts on, top covers, fill the fluids back up and she'll be ready to go. Again, I'll make a new thread with either pics or links to my geocities site with detailed how too.

I had to get the intake cam from the dealership given that I don't have a lot of time to mess with this car...my girl needs it back and soon. But I might get a spare just in case...although I don't think that will be needed as long as I keep an eye on the tensioner.

So here is why these parts wore so much so quickly...the upper chain tensioner wore completly out, it's only hard plastic after all. Once this happened the chain had slack. The plastic was worn completly off, you could see the metal piston underneath it.

As a result of this slope in the chain, it wore the sprockets. What I will do is at 30k take off the covers and re-inspect the tensioner. It's not hard to replace/check and not too expensive to replace at around $50 for the tensioner.

The lower chain guides were not worn hardly at all, it's just the design of that tensioner...so much pressure is placed on one spot...with the lower tensioner they are longer and the chain doesn't push tightly on ONE spot. 

The lower sprocket was not worn at all...but it came with the kit so it got replaced.

The water pump turned quit freely and the new one is much tighter, could have left the old one on but if it comes off a new one is going on.

My camera crapped out so I don't have pics of the re-install process...I'de really cleaned up some parts quit nicely but oh well...you'll just have to take my word for it. I'll post more detail in the other thread I creat later.

All in all this isn't hard to do, everything is WAY easy to get too...the p/s pump has a little trick to getting it off. If you don't have car ramps this will be MUCH harder as to get to the majority of things it is VERY easy if done from below.

to get the p/s pump off without the car raised up is a pain. The FSM download doesn't really explain well how to get the pump off..it leaves out the nut on the back of the pump you have to remove to get 'er to swivle. Any hoo more later.


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## evgready (Apr 15, 2007)

*HELP...ELP..LP...P!*

hi there!.
Well 
I did the same thing to my Wife's 97 sentra with the same engine, and with the upper tensioner worn out. I replaced the upper tensioner and the rattle kept going. Then I decided to replace both chains and the lower tensioner...water pump..seals, etc... I got everything on, ready to go...put fluids and started the engine.

It had always ran just fine...and when I replaced all the chain components , they were intact. The only one that was worn was the upper tensioner (the plastic part). 
Any way... after all that work...new seals..etc.. 

I still have the rattle on the upper tensioner area. I am now inclined to start the engine without covers ( bold move) to find out what is making noise. Has anybody had that same issue with this engines? 
This engine has only 130k and always changed the oil. The engine inside looks spotless!! 
I noticed that the intake cam has a big bulky looking cylinder sprocket..what is that? Can that be a mechanical advance that could rattle somehow?

Help!

Edgar


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## IanH (Feb 11, 2003)

evgready said:


> I noticed that the intake cam has a big bulky looking cylinder sprocket..what is that? Can that be a mechanical advance that could rattle somehow?
> 
> Help!
> 
> Edgar


yes this is the VTC, its operated by oil pressure, turned on and off by the ECU
I doubt this would rattle.
I only have 100 k on mine and have yet to experience the noisy chain problem, sorry I cant help further.
Try listening with a large screw driver as a stethoscope.
good luck........


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## Tavel (Aug 21, 2004)

IanH said:


> yes this is the VTC, its operated by oil pressure, turned on and off by the ECU
> I doubt this would rattle.
> I only have 100 k on mine and have yet to experience the noisy chain problem, sorry I cant help further.
> Try listening with a large screw driver as a stethoscope.
> good luck........


for those in the dark, VTC is the variable valve timing controller. :cheers:


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## schoust (May 27, 2008)

Anyone ever figure out what evgready's rattle was? I have a similer noise but don't have the money to be changing parts on a high mile engine.........


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