sorry to hear you have to take the cover off again. I am sure I smeared the Permatex all over while I was fumbling to get it put back on, but so far no leaks. And with the difficulty involved in gettig it off, it's gonna have to leak pretty bad for me to take it off again rather than just top off the oil every once in a while.
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Tim the diesel man
1990 Stanza 206k miles...make that 212k..214k...237k
Hey, I'm having the EXACT same issues you were - it's jumped a few teeth and appears to be about 30 degrees out as well! I was wondering how you knew where to put everything back in time? I can get the crank lined up TDC no problem...but I'm not 100% sure where the cam is supposed to go and I don't want to screw it up and cause any damage! Do you remember where the cam is supposed to be? I only see 2 points of reference on the cam...there's the keyway, which is visible, and then there's a little circle stamped near one of the teeth. Right now they're not looking like they're anywhere specific...kind of in the middle so to speak - if you know what i mean? Can you help me out with this?
Other than that, I appreciate you telling your story - sounds like there's a few things in there that are sure to save me some time!!
Any help would be greatly appreciated.
Craig
EDIT: Also, the book I have is completely USELESS when it comes to this...makes absolutely NO mention of where it goes. It tells you to mark everything when you take it apart...but obviously that won't do me any good! Thanks.
Last edited by CraigChats : Dec 20th, 2007 at 08:11 PM.
Reason: Added info...
Hello Craig,
From reading your post, I suspect the guide and or the tensioner broke. Both are plastic. In my case, the guide mechanism disintegrated and fell into the oil pan allowing the chain to skip teeth.
I would HIGHLY recommend buying a timing chain "kit" from ACME or Napa. Its about $150 and includes the chain, cam sprocket, crank sprocket, and all guide/tensioning assemblies. You will also need separately an oil pan gasket and for good measure, it probably wouldnt hurt to get a valve cover gasket as well.
The car is almost 20yrs old at this point and probably has a lot of miles on it. Something bad happened to make the timing go out of whack, and just realigning crank to cam positioning is putting a band-aid on the problem, not solving it.
Before you put any $$ into the car, do a compression check. If it's not holding compression, you've got top end problems like bent valves or scored valve guides and that makes your life much more complicated.
If it's holding compression, you got lucky and your top end should be ok.
You will need to know where TDC is (approximately) on the #1 cylinder, so stick something (SOFT!) into the #1 plug hole and bar over the engine until that is near. You can verify that you are at TDC on compression stroke vs exhaust stroke by checking the position of the rotor in the distributor. If the rotor is near the #1 plug wire location, then you're all set. Find TDC, or approximately TDC before you tear into the car. It makes things easier down stream
As far as crank to cam timing goes, there are indicator marks on both the cam sprocket and the crank sprocket. The marks need to be aligned with one another and that will properly phase the cam to the crank. You don't want to be off by one tooth because then the car will run like crap and fixing it means tearing everything apart again.
Make sure you account for all of any broken bits and pieces because in my case a piece of the guide wedged itself between the chain and the oil pump sprocket and cracked the oil pump cover. Oil pump is contained within the timing cover. If the pump is damaged in any way, replace it. Oh, and make sure to pack it with vaseline before reassembly to prime it.
Also, if you live in a climate where there is salt put on the roads, pay CLOSE attention to the oil pan. My oil pan had corroded to the point where oil was seeping through the metal. You can't get new pans from Nissan, so it's off to the junk yard you go.
Hope this info helped. Let me know if there is anything else I can help with.
Tim
p.s. I have 40k+ miles on my new timing chain and all is well. Total miles on the engine now is north of 270k.
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Tim the diesel man
1990 Stanza 206k miles...make that 212k..214k...237k
Hi Tim, first let me say thank you very much for replying to my post, and for all your help and advice - I really appreciate it!
I didn't say it in my post, but I'm planning on changing everything. I've removed the valve cover and confirmed that the guide is indeed broken, as I suspected - I found a piece of it sitting in plain sight when I looked down the cam chain! The car has about 180k on it so I figure it's best to change the whole parts lot - the chain, tensioner, gaskets, etc. and maybe have a very close look at the oil pump, too. The engine has got decent compression, and even better all of the cylinders are fairly even - they're all within about an 8 psi range highest to lowest! Needless to say I'm happy with that.
I've been going over the whole job - in my head, on paper, in online posts, and in the book...to make sure I have the whole thing down before I start, and to learn what to watch out for, and I've learned a LOT here that I'm sure will save me a TON of time and energy. So far I think I've got the whole thing down - with the exception of the exact alignment of the cam. I'm sure I'm just missing something here...but I can line up the crank using the timing indicator marks on the pulley...I found the mark for TDC and CAN line the crank up with no problem.
Where I run into problems is the cam - I found the mark on the cam sprocket (basically a small circle stamped into the sprocket near one of the teeth) without much problem....however, the problem is that I DON'T know where the other mark is. Where is the timing mark that I would use to line up the mark on the cam up to??? Does that make sense? Basically I can set the cam anywhere - rotate it 360 degrees...I need to know where I should line the mark on the cam up to? Any help/ideas would be greatly appreciated - as this is about the only thing I can see holding up the job right now, once I figure this out I'll be tearing into it and fixing it!
Oh yeah, forgot one last thing - as far as parts: I was going to go to NAPA for the parts kit and other misc. parts, but then I saw a parts kit available online (I forget exactly where or how much - could look up specifics again without much trouble) BUT it was CHEAP!! If I remember correctly it was somewhere around maybe $50 or so! My thing is that I'm a firm believer in "you get what you pay for" philosophy, and I'm worried I'll be getting really cheap/low quality parts. Anyone have any thoughts and/or experience with these types of parts? I'm thinking I should stay away and go to NAPA...or maybe just go even one better and just go directly to Nissan for the parts...? Some input would be great here to - saving money is good - but....?? I'm planning on getting them ordered from (wherever I buy them) the day after Christmas in hopes to do the job next weekend. (Not in a hurry to get this done at all tho, as I have another car to drive until this gets fixed...just want to do this correctly!)
I know this is an old thread but i thought i would give it a try, I too am in need of a timing chain, only 100k on the car but the previous owner didnt care for the motor. Anyhow, i don't feel confident taking this on my self and cant afford the 1200 or so in labor to pay a mechanic and i was wondering if anyone in the philly/ south eastern PA area would like to help me out, at least make sure i do it right/safely.
Hi there,
When you buy a timing chain "kit", it will come with the sprockets, chain, nylon guide and nylon tensioner assembly. Replace everything. Also, you will need an oil pan gasket, and most likely a valve cover gasket too. I've put
50k miles on my new timing chain and the car still runs like a top. Current estimated total mileage is 275k (odometer doesn't always work). No leaks, no problems.
I'll keep an eye on this thread, so if you have any more questions, please post them.
Hope I was a help.
Tim
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Tim the diesel man
1990 Stanza 206k miles...make that 212k..214k...237k
I would assume so. My mechanic was stern on replacing everything associated with the timing chain, including water pump.
Hello, new member here and my first post, writing to you from SF, CA.
There is nothing to question when it comes to replacing the tensioner and all the other parts while the timing cover and other parts are off. If you know how much work is required just to get the timing cover off you'd change everything possible. I would also change the two coolant hoses which pass underneath the intake manifold, with the PS pump out of the way it's a pretty clear shot from underneath.
I am doing this repair right now (posting this from the garage) it is a total pain in the ass, I swear I'd like to slap the idiot who thought it was a good idea to design the timing cover such that the oil pan has to be removed. If it weren't for that the amount of work would be significantly reduced, what a PITA this is. I never want to do this again. I have taken some pics and will post some shop manual pics and some other tips as well to help out the next poor soul that has to do this. I will also post pics of how the timing is set.
Buy a complete timing set with a water pump, timing chain/sprockets, guides, oil pump and pickup seals, crank seal. Might as well buy a new valve cover gasket while you're at it, of course it's a good time to change belts too. In fact you should check the front and rear (left and right when facing the crank) motor mounts. It's a good time to replace them while you have all the crap apart.
Use Permatex ultra grey or Hondabond for the timing cover and oil pan. It is designed for this type of use, cures semi hard and seals great. Also excellent for sealing the corners of the valve cover gasket where the humps for the dist./cam are. Well, back to work, gotta clean the oil pan and replace the chain/other stuff and start putting it back together.
This sucks. Ok so I now see I have a cracked oil pump housing, when the plastic from the guide went between the chain and the sprocket it caused the chain to crack the pump housing. Thinking I should have just donated the car instead as this is just a run around spare car, but it is fun and a very good car. My original thought that swapping the engine might be less work is turning out to be correct and I think I'd rather do that than do this repair again.
This sucks. Ok so I now see I have a cracked oil pump housing, when the plastic from the guide went between the chain and the sprocket it caused the chain to crack the pump housing. Thinking I should have just donated the car instead as this is just a run around spare car, but it is fun and a very good car. My original thought that swapping the engine might be less work is turning out to be correct and I think I'd rather do that than do this repair again.
So I checked the cam timing and it's waaaay off, I would say perhaps 30 degrees or more. So it's off with the head, have most things off anyway, so I'm gonna port the head and then have the head reworked. Might as well port the exhaust manifold too. One of the rocker arms is spongy, gonna take it apart and clean up the lifter then pump it up while submerged in oil.
I've also been taking pics so I'll start posting some soon. BTW I ordered a new oil pump/timing cover, the guy I buy from sold it to me for $110 including next morning delivery from SoCal to NorCal.
My lifters went too. I tried soaking them in parts cleaner and then in motor oil for a good long time and then reinstalled them. That helped for a few weeks, then they started making noise again. You can still get lifters from Nissan. They aren't as expensive as I thought they'd be and are a piece of cake to change.
Check compression before you take the head off and tear it apart. 30 degrees of cam timing is only 15 degrees of crank timing, so you might not have any piston/valve clash after all. I don't know how far mine was off, but I had decent compression and no bent valves.
My car was/is a New England car and because the exhaust passes directly underneath the oil pan, it goes through some extreme cold/wet to hot/dry cycles and if you add road salt to the mix, that meant that my oil pan had corroded to the point where oil was oozing through the pan. I cleaned it up and if I held it to the light, I could sort of see through it...not good. Nissan no longer makes the pan for this engine, but I was able to find a decent one at a junk yard. I cleaned and painted it so I could keep an eye on any leaks that might develop. None have.
Let me know if you have any more questions. Good luck.
Tim
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Tim the diesel man
1990 Stanza 206k miles...make that 212k..214k...237k
Unfortunately all four pistons show the telltale sign of being kissed by the intake valves. Interestingly none of the exhaust valves hit. Only one lash adjuster is spongy, I didn't know you could change the lifter only, I thought you just replaced the whole rocker arm, guess I'll have to look into it. The condition of the cylinders is great, no ridge, clearly visible cross-hatch marks in the cylinder bores after 179K miles. Cleaned off carbon deposits and prepped block, going to drop off the head at the machine shop today.
I too had the 'timing chain guide broken' problem. I thought it was the head gasket (water in oil) so replaced that. Then I looked at the timing chain cover and saw where the loose chain had gnawed through the aluminum into the water channel from the water pump, so I replaced the front cover, and the two guides and the timing chain tensioner but not the chain itself. (In retrospect it would have been much cheaper to buy a timing chain kit on ebay. Much cheaper.) Put it all back together but can't get it started.
Here's what I think but any ideas would be appreciated:
1. when I put the chain back on the camshaft sprocket and the crankshaft sprocket, I had the little 'woodruff keys' on each pointing not straight up, but maybe five degrees to the right. Why? Because that whole engine is on a slight angle to the right AND that is the way the picture looked in the Haynes Manual. Was I wrong? I think so because when I try to start it, it fires and almost starts but never quite gets around to it.
The distrib timing I got from here somewhere - the guy said to put the oil pump in so the straight part of the 'D' is just before 12 o'clock when you look at it through the distributor hole. That works okay because it allows you to set up the distrib rotor pointing at exactly the middle of the connection on the distrib cap for the #1 wire. So that's okay, I try to start it and it coughs but won't. I retard it and advance it and surreptitiously kick the front tire while pretending to study the engine. Nothing.
When I turn the Crankshaft by hand to get to the TDC mark on the Crankshaft pulley, the compression comes quite a ways before the TDC mark. Which might indicate something to a mechanic but I'm not. I know it is supposed to fire at 10 degrees Before TDC but the compression I feel seems to come even earlier than that.
The thing that bugs me is when I do get to TDC on the compression/ignition stroke and I have the valve cover off, there is the the woodruff key on the camshaft sprocket pointing just slightly to the right of vertical - exactly where I set it when I had the front cover off. That is to say the timing mark on the front cover is pointing directly to the TDC mark on the pulley (second to last mark as you turn the crankshaft clockwise. that is, second mark in from the left when you are facing the engine) and the woodruff key is just to the right of vertical. And yes, I even put the two brighter links in their respective places vis a vis the sprocket timing marks. Could it have slipped a notch when the camshaft bolt was torqued down?
2. I would think that the chain is too stretched to be any good but the truck ran fine before - even with water in the oil it drove (until I realized there was water in there and stopped)
So what do you guys think? Should I go back in there (for the third time, but I don't bother taking off the oil pan - just remove the front six bolts on it and use a claw hammer to gently pry the cover off, there's place on either side you can get a purchase WITHOUT putting anything between the cover and the engine. I think I got that from this site as well) and set the chain so the camshaft woodruff key is pointing straight up or even back a tad?
3. It is possible that the whole chain skipped a notch when I was tightening the camshaft sprocket bolt. I did hear a loud sort of CRACK sound, but the goldarn thing looks, as I say, to be set up exactly right!
Any ideas would be appreciated. If nothing else works I guess I will set it up once more and if that doesn't work, take the head off and see if any of the valves are bent. (thought there is good pressure when you crank it by hand)
Any ideas would be appreciated.
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