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View Full Version : Timing chain and headache..


AllThingsGravy
02-20-2016, 09:22 PM
My 92 s13 has a ka24de and ran pretty good. Burned oil here and there but was peachy for the mileage (220k) but it had a little knock coming from the valve cover that was starting to get worse and annoyed me so one today I took apart the valve cover and upper front cover to discover that the timing chain is smacking the top of the valve cover. I know this is what is causing the noise because the valve cover has marks on the inside that indicates its lose and hitting it. I thought there was too much slack so I decided to change the upper tensioner only and that it would fix it. So I put it back together and it was still the same but a little worse. Now it was making itself present even more and was hitting harder. I drove it around the block and nothing was different except the noise was more constant but after driving it for a while the car bogged and would not start back up (timing chain was out of control). Mind you this is all the same day. I got the car towed home and I took everything apart again and looked at the tensioner and saw it wasn't bolted completely to the block (my mistake) and was not putting a ton of tension on the chain. So I tightened it and put everything back but once again I turned on the car and the noise is still there. At least the car starts now but not in drivable condition. I was reading that the chain might be stretched but I'm not sure, also the top 2 guides were removed already so that's not the problem. I also have not ruled out low oil pressure. So yeah any help is appreciated guys.

TL;DR

-Car was fine with a small rattling from the front valve cover at 2-3k rpms non existent with foot off throttle.

-Changed upper tensioner only and didn't fix. Made car worse

-Car broke down would not start because chain.

-Took apart again to see again what happened. tightened tensioner to see if would work, turns on now but constant smack on the valve cover...

AllThingsGravy
02-20-2016, 09:34 PM
Update: Pretty sure it has a rod knock

KAT-PWR
02-20-2016, 10:48 PM
Sounds like oil pump is on its way out. Did you check oil pressure?

AllThingsGravy
02-20-2016, 10:52 PM
How did you tighten the spring loaded oil fed tensioner?
Sounds like oil pump is on its way out. Did you check oil pressure?

Well I looked at the tensioner bolts and the top stripped the block so I rethreaded the top and got a longer bolt and it was a better fit. I have a video of the car running but I'm sure it's knocking.

AllThingsGravy
02-20-2016, 10:53 PM
Have not checked the oil pressure yet.

KAT-PWR
02-20-2016, 10:55 PM
Well the chain guides are spring loaded then backed by oil pressure. That would be the first thing I would check after verifying that it was guide pieces being smacked around.
Upper chain is obviously easiest to see, but the lower chain if there are guide/tension issues has a lot more room to move around.

AllThingsGravy
02-20-2016, 10:57 PM
It forsure isn't the guides.

AllThingsGravy
02-20-2016, 11:05 PM
Well the chain guides are spring loaded then backed by oil pressure. That would be the first thing I would check after verifying that it was guide pieces being smacked around.
Upper chain is obviously easiest to see, but the lower chain if there are guide/tension issues has a lot more room to move around.

The top of the timing chain is hitting the valve cover I'm sure if it isn't knocking.

http://imgur.com/tbHTH9t

Itsuki Takeuchi
03-07-2016, 12:58 PM
Did you ever figure out why your chain was hitting the valve cover? tensioner? Low oil pressure? Upper Chain?

AllThingsGravy
03-07-2016, 01:01 PM
Did you ever figure out why your chain was hitting the valve cover? tensioner? Low oil pressure? Upper Chain?

It was low oil pressure or a slacked chain, but since I know it was low oil pressure the engine threw a rod. So it was a rod knock rather than the chain hitting.

ZaK687
03-07-2016, 02:00 PM
Could've also been a faulty oil pump , since the tensioners run off oil pressure

Itsuki Takeuchi
03-09-2016, 07:54 AM
damn that sucks.

my current issue is the chain is hitting the valve cover. i swapped out tensioners. i gonna try to take it back off and clean it real good with brake cleaner. it seems as if the noise comes and goes. i used a stethascope and its the chain hitting the valve cover.

maybe the chain needs replace? can a chain really strecth over the years that much without breaking.....

on my spare motor, i practiced taking off the chain and putting it back on. When i did, noticed that chain markings (colored chain links) did not match up with any of the dots. and yes the crank pully and everything was on TDC. it was off a half of link. i tried moving the chain to the correct position when putting back on but there wasnt enough slack to do so. (yes tensioner and guides removed) will that make a difference? the chain being about half a link off from the dot marking? and it wasnt any where near it when i began. i moved the chain so the (shiny links) would line up. the engine ran fine before pulled btw.

cotbu
03-11-2016, 03:45 AM
Tell me how you got the chain on with a half link off, that needs pictures. I mean I never purposely tried to f up the mechanical timing, so I'm not sure this isn't possible. I do know you don't try to move the chain. That's idiotic! You move the cams.

So, you have a spare motor you can practice doing basic things wrong on huh!

Itsuki Takeuchi
03-11-2016, 08:44 AM
Tell me how you got the chain on with a half link off, that needs pictures. I mean I never purposely tried to f up the mechanical timing, so I'm not sure this isn't possible. I do know you don't try to move the chain. That's idiotic! You move the cams.

So, you have a spare motor you can practice doing basic things wrong on huh!

dont be a :mrmeph:

i didnt explain right and or not understanding my statement.

Aftert much research I found that only after so many revolutions of the crank will the chain line up perfectly.

pictures ive seen/ the dots on the cam gears line up with the shiny links on the chain. Mine was not lined up.

So My question was do I line them up when the cam gears and chain are off or will that change the timing doing so. I put it back on exactly how it came off......So its in the correct position.

but thats all beside the point......

i want to know if my chain is bad or can go bad over time?
i have removed my guides and replaced the tensioner with a working one.
i dont have as bad of a chatter now idling but there is chatter around 2500-3000 (the loudest) and so on. there are marks on my valve cover where it has been hitting.

I dont have a knock. It only chatters under 1/4 of throttle.

and the noise i hear idling- well i used a stethascope and its my injectors. they are loud.

I just had the front of my engine torn down last night checking everything. Both my lower chain guides are great condition and the tensioner is functioning. theres no marks or sign that the lower chain has slack.

the upper chain looks good, tensioner working. guides removed. signs of it hitting the valve cover. its not gouges just shiny spots of wear.

i guess ill have to live with the sound until somthing fails. i cant source it.

P.S.
It currently running and driving. drove my 30 min commute to work this morning with no issues. but the noise is still there.

cotbu
03-11-2016, 02:20 PM
Your chain question is kind of idiotic, because....your "go bad" is insinuating that it shrunk. It can stretch but in your case its installer error.
The noise is probably the lifters. Your should bleed them. You could have spent time wondering around the interweb to help you with all problems you could ever possibly face in life, here on earth 2.0
I've participated in multiple mechanical timing threads so I know they're here! G/L

AllThingsGravy
03-11-2016, 02:26 PM
dont be a :mrmeph:

i didnt explain right and or not understanding my statement.

Aftert much research I found that only after so many revolutions of the crank will the chain line up perfectly.

pictures ive seen/ the dots on the cam gears line up with the shiny links on the chain. Mine was not lined up.

So My question was do I line them up when the cam gears and chain are off or will that change the timing doing so. I put it back on exactly how it came off......So its in the correct position.

but thats all beside the point......

i want to know if my chain is bad or can go bad over time?
i have removed my guides and replaced the tensioner with a working one.
i dont have as bad of a chatter now idling but there is chatter around 2500-3000 (the loudest) and so on. there are marks on my valve cover where it has been hitting.

I dont have a knock. It only chatters under 1/4 of throttle.

and the noise i hear idling- well i used a stethascope and its my injectors. they are loud.

I just had the front of my engine torn down last night checking everything. Both my lower chain guides are great condition and the tensioner is functioning. theres no marks or sign that the lower chain has slack.

the upper chain looks good, tensioner working. guides removed. signs of it hitting the valve cover. its not gouges just shiny spots of wear.

i guess ill have to live with the sound until somthing fails. i cant source it.

P.S.
It currently running and driving. drove my 30 min commute to work this morning with no issues. but the noise is still there.


Your symptoms are exactly how mine were (not loud until 3k-4k) etc... I said the same thing that I would drive on it until it fails and that's where my rod knock came. Check your oil pressure and oil level constantly is my advice. I don't want you going through what I went through.

Kingtal0n
03-12-2016, 06:04 PM
some things that contribute to rod knock on sr20det engines:

1. Running the car hard before the oil thins out enough(idle pressure needs to be seen to drop to 10-25psi range, I usually see 20psi for every 1000rpm on a stock engine after that i.e. 2000rpm = 39psi of oil pressure)

2. Using the wrong weight oil. Stock bearing clearance and very cold climate is 5w-30, go somewhere like Fl and its 10W-30. High mileage, 150k+ engines in Fl weather get 10W-40. Nothing gets 50W with a stock bearing.

3. Revving the engine too high, repeatedly striking the OEM Limiter, thrashing/abuse, especially in conjunction with #1 and #2

4. Too much timing advance for wide open throttle during boost with an original engine on OEM hardware. 15* btdc is too much for daily drivers with stock engines. It should be around 9*.

5. Opening the engine, even for an oil change, without being clean about it, allowing debris or filth to get into the engine will block the many tiny orifice.

Itsuki Takeuchi
03-15-2016, 07:54 AM
well i figured out my sound. it was and is the timing chain. its made more of a mark on the valve cover.

i put the top guide on to prevent it hitting the valve cover, and ordered a new tensionor as its clear mine has failed. I attempted to clean it out with brake cleaner and it work good in my hand. but when installed it seemed as the spring was worn out and wouldnt hold enough tension on the chain. i figured when oil pressure rose it would push it out. i dont think it has at all. its still in the same position and i cant compress it while install.

but with the guide back on top the noise has almost completly left. its still smacking the guide. i put it in just to kinda double check that its the timing chain making the noise.

Im also flushing/cleaning the engine out with marvel mystery oil and changeing the oil today. as its becoming hotter out ive decided to go with a heavier oil. Mobil 1 synthetic. Royal purple didnt have the weight i needed on the shelve. need to look into ordering some good stuff. eunos? hks? any other oil companys that might good?

Itsuki Takeuchi
03-15-2016, 08:00 AM
Your symptoms are exactly how mine were (not loud until 3k-4k) etc... I said the same thing that I would drive on it until it fails and that's where my rod knock came. Check your oil pressure and oil level constantly is my advice. I don't want you going through what I went through.

will do. also im changing the oil after work today. im going to cut open my oil filter to see if it has collected anything that shouldnt be there. Maybe shavings from a rod bearing n such. i doubt it though.

i had my woman help me rev the car up and down for me as i listend through a stethascope. and theres no sound from the block on either sides.

main things i picked up on was the upper timing chain cover and holy batman my injectors are loud lol :eek: