slack in 22re timing chain

chuckwhut

chuckwhut

Well-Known Member
Joined
Oct 6, 2005
Location
Concord, NC
Well it's been clattering, and with all the oil seeping out of the valve cover, figured i go ahead and do my valve cover gasket etc....and while i was in there check to see if the timing guides were broken. They are intact, but there seems to bee way too much slack in my chain...
This might sound stupid, but is it only tight at TDC, cause i have not set it to TDC.
With that dumb question out of the way, here comes dumb question number two...HOW CAN I TAKE THE SLACK OUT
I am really hoping there is a simple solution that does not involve pulling the timing chain cover etc....please help!
guides intact, cover off pic...
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chain slack pic...this is too much slack, right?
486414971_l.jpg
 
the hydrolic(sp) tensioner is probably going as well as the guides. its not that big a deal if it jumps the chain or jumps time cause its a non-interference motor i.e. the valves can never contact the pistons
 
Metto said:
the hydrolic(sp) tensioner is probably going as well as the guides. its not that big a deal if it jumps the chain or jumps time cause its a non-interference motor i.e. the valves can never contact the pistons
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Um, this is incorrect. This is in fact an interference motor. Hence - do NOT let it jump a tooth.

It does indeed have some slack w/o oil pressure, the tensioner is oil pressure driven. However it is also spring-loaded so it shoudl still be pushing out all teh time. Do you have to pull on the chain a little to get the slack, or is it really just hanging there?

Aside from just being a worn chain, or the guides are broken (you clearly are aware of that issue), do you knwo the history on the block/head? If either/both has been shaved, this wil ladd a little slack due to decreases cam-to-crank distance.

Oh and re: TDC, if I recall I remember the "tension" on teh rank being highest just before TDC, then backs off as it goes down. *however* what I refer to is the tension felt turning the crank pulley, which is mostly due to the piston position. The relationship between crank and cam should be constant.
 
Um, this is incorrect. This is in fact an interference motor. Hence - do NOT let it jump a tooth.
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yeah, that's what i thought...
It does indeed have some slack w/o oil pressure, the tensioner is oil pressure driven. However it is also spring-loaded so it shoudl still be pushing out all teh time. Do you have to pull on the chain a little to get the slack, or is it really just hanging there?
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well, that's hard to say. i don't have to force it at all, the pic of me pulling the chain away from the gear..i wasn't pulling hard. just basically pushed at it to see if there was slack, and when i saw that much slack it sparked my concern.
Aside from just being a worn chain, or the guides are broken (you clearly are aware of that issue), do you knwo the history on the block/head? If either/both has been shaved, this wil ladd a little slack due to decreases cam-to-crank distance.
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yeah, i thought about that...i'm not sure about the history of the engine...maybe chase has more info on it? i bought it from him, and he said it was supposedly rebuilt about 50,000 miles ago, if i remember correctly. but since he isn't the one who did it/had it done, i'm not sure if he knows either.
in regards to oil pressure, i am running 10w 30 and i have added some lucas oil, but i am being advised on PBB to:
you should never run a motor with 250,000 on 10w 40. that is half of your problem right there. run 20w50 immediatley so you dont ruin the whole thing.
think about it -- if your chain tensioner is hydralic and everything else looks in tact and youre hearing clacking from the chain its probably because (like the reaper said) you dont have enough oil pressure.
my recomendation -- change the oil and filter NOW! dump it and change it again (and the filter) in 100 miles. repeat this process one more time. somewhere in between hook up an oil pressure guage to it and check what your pressure actually is.
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Quit using 10w40 oil. That black s--- is from the over abundance of parifin wax in 10w 40 dino. It may have clogged up your rings and the source of your oil burning. Most auto manufactures tell you not to use 10w40 now. Hell My 88 Suburban point blank says they will void the warranty on the engine if they find you run 10w40 in the owners manual.
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whaddaya think? i know less about oil than i should:D
 
I not sure on toyota motor. but others I have seen do have a guide that adjusts with oil pressure, but is has a ratchet so once it goes out it will not go back in. if your chain/sprokets are too worn then you need to replace the timing set. it should be a cheap and easy fix compared to a bunch of bent valves.
 
the chain and sprockets do not appear to be worn at all. most TC kits i believe come with a new tensioner, if not i would assume most people would put on a new one unless they were being real cheap.
i guess it's a man-made mechanical piece, so even a brand new one in theory could go bad in no-time.
i'm really starting to lean towards the oil pressure thing, however like ratlab said "it is also spring-loaded so it should still be pushing out all the time"
so that kinda makes me lean towards the milled down head thing....AAARGH!
 
loose

I would install a new gear set. Should include both gears, chain, guides, tensioner and gaskets.
 
Larry, i might end up doing that...i'm just trying to explore my options before it comes to that since this is my DD, i want it back on the road ASAP! so i thought i'd get some opinons on the severity of the slack as demonstrated by the pic, and if there was any way to take out slack without tearing down the whole engine!
nobody has really mentioned this yet, but does that seem like an excessive/dangerous amount of slack, or am i being paranoid?
 
When talking about the shaved head then it is hard to say how much has been taken off. Most Aluminum heads need to be surfaced when they are taken off. Not all. Usually .010 to .015 is all it takes to clear the surface up. Of course more could have been taken off, hard to say. Using OEM gaskets I have not heard of anyone having issues with slack in the timing chain due to how much has been taken off the head. Bear in mind, the roundy round guys take a LOT off a head raising compression, and they don't have issues with this.
 
you are probably being paraniod, a shaved head, half worn chain and sprockets, combined with slightly worn tensioner, and poor oil pressure will give you some slack. If the chain was in fact slapping around in there it would have broken the plastic guides. i have seen many 22re that run fine and the guides are in the oil pan and the chain is halfway throught the T-cover if not all the way through and they haven't jumped time yet. I guarante you can get another 2 years, 25k miles out of it if not more with out looking at it. I run rotella 15w40 with lucas additive. 20-50 is a little thick for winter time use i think. put the PBB guys may be right. I would just check the guides every five months or so and make sure they aren't broke. replacing the oil pump maybe a good idea, you can do this with out major surgery. plus i bet the racket is the valves adjust the valves and put new adjuster screws in. 15w40 and rotella it will quiet down.
 
and to put a new chain, sprockets, ect you need to pull the head. t-chain kits with everything included are only about $60 from enginebiulder. if you are really worried about it drive it up here and we can throw one on.
 
Cperry said:
and to put a new chain, sprockets, ect you need to pull the head. t-chain kits with everything included are only about $60 from enginebiulder. if you are really worried about it drive it up here and we can throw one on.
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I didn't pull the head when I did mine. Did take the oil pan and VC off, but not the head.
 
I've see the guides break at the bottom so that they appear to be intact from the top, but when the oil pan was pulled the majority of the tensioner is in the oil pan. If you can swing it, the LC double row kit with metal guides is awesome. If you don't want to drop the dough on the LC kit, at least get some metal guides from DOA racing. It's worth the extra money to never have to worry about the timing chain again.
 
well, i have some serious leaking going on from my oil pan, so i will be pulling that either tonight or tomorrow or something...i suppose while i'm in there i may be able to get a view of things from underneath...i will decide from there whether or not to start taking pulleys off i guess, depending on if i'm satisfied. haha! i was gonna adjust the valves last night when i first took the cover off, because i think you're supposed to do it with the engine warm, am i right? if so i will reassemble everything, and start it, let it warm up, then take the cover off again then do the valves! hell, at least it gives me something to do, right! haha
 
You do not have to pull the head to replace the timing stuff. I have done it w/o it. There is a complete writeup on 4Crawler's website, step by step.
The biggest PITA is that you have to pull the timing cover... and every damn thing is attached to that thing. The whole job can be done in a Saturday though if you bust a$$ and know what yer doing.
Too bad yer on Concord Chucknut, I could help out if you were nearer to winston, been through it twice now + one total engine rebuild.

is there a reason you suspect low oil pressure? Remember that as you witness it now, there is no pressure. It *could* be that the spring in the tensioner is just worn out so it dosn't hold it very tight right now, but if it isn't leaking/failing it works fine when running.

Just to quantify yer slack here so we know, a few questions. Is this from pulling the crank pulley clockwise (as facing) or counterclockwise? 22re's native state is clockwise, but if you switch directions you'll notice a little freeplay before the cam picks up again.

Been thinking about this. If you are turning the crank clockwise, the slack should only be on the opposing side (passenger side) - that is where the tensioer is. I would think then the slack should be much less that way b/c the tensioner can push out (assuming good spring) to compensate. In contrast, if you turn the crank counterclockwise, the slack is left on the driver's side, since you are "pulling" that tensioner in, it should be greater. This is how it looks you have it in your picture.... remember that the motor will never natively be in the position you have it right now....

i remember on mine I could just about stick a screwdriver through a tooth and under the chain. Just "some" slack. As long as it is not enough (or real close) to enough that you could pop it off or jump a tooth, you should be okay.
 
chain

You do not have to pull the head to install the gear set. You "must "remember to remove the bolt running through the head into the timeing cover. It is located directly in front of the bolt holding the cam gear on the cam in the bottom of the area the distributer driven.
 
Just b/c you have metal guides does not mean you never have to worry about the timing chain again. I think dual row chains are overrated(a decent chain kit will last a 100k and many if all of this will never put that many miles on one). Engine biulders kit for $60 has driver side metal guide b/c that is were the slack is. Slack is on driver side not on passenger side b/c tensioner is taking up slack on pass. side. if you rotate counterclockwise it will take up the slack on driverside and tensioner on pass side.

yes it is possible to do it without pulling head, put you disrupt the head gasket and oil usually leaks at the cover.Scheduled maintance i believe is every 100k. So buy pulling the head you can replace the head gasket evry 100k a good idea i think, service injectors, new valve seals, and polish valves have it vacum tested. all this stuff needs to be done at a 100k or if you are going to go threw the trouble of putting a t-chain on it, why not take care of the rest of the top end while your at it. Otherwise you go threw the hassle of doing the chain with little benefits. The right way is to pull the head.
 
adjustment of valves can be done cold i would set to 11 and 7 instead of 12 and 8 b/c you have to be seriously motivated keep it warm while doing it. but if your adjusting screws are chipped or miss worn they are still going to clack. even 12 and 8 warm can still be loud. some 22re just sound like little diesels i don't think it is a problem.
 
chuckwhut said:
i haven't turned anything though. i "turned" the truck off...got out, and pulled the cover, haha. this is how it was when i found it.
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Ah. So maybe you are a little ahead of yerself then. If you want to check out the slack and timing, get a 19mm bolt and turn the crank clockwise and then see how it it, thsi is more realistic. While yer at it set it to TDC so you can check the valves as Chase mentioned. This is a good way to assess if the chain it stretched or something, b/c when the crank is at 12:00 TDC, the notch/hole on the cam sprocket will be just shy of this, like 11:55. If yer off, it would be less than that.

As I said, do you have some reason to believe the oil pressure is low, or anything like that - or is it simply that you pulled the valve cover off just for the hell of it and check on those guides, saw a little bit of slack in the chain?

Chase, I do not mean to be an a$$ but want to clarify something you said b/c at first it was confusing to me. The driver's side, where the long guide rail is (that SHOULD be metal-backed) is in fact NOT slack when the engine is turning. This is b/c the crank is moving clockwise (as you face it) and is using that chain to pull the cam sprocket. Meanwhile the other (passenger) side is naturally slack when in motion, that is why there MUST be a tensioner on that side, to keep this slack away so that the chain is tight on both sides, and descreases chances of slipping a tooth.

When the engine turns off, crank will stop due to friction, and cam wil lstop b/c it's no longer being pulled by the crank. However if/ b/c there is a difference in the native friction between them, the cam may turn just a litte farther, causing the slack that is seen in the above picture.
The tension of the chain is the largest issue when you first start up the motor - there is a brief moment when the crank is moving faster than the cam , before the chain "grabs". if there were a whole lot of slack on the opposing side, thsi would be a great time to jump a few teeth. However since the chain tensioner is there, and spring loaded, it keeps this from happening - and of course once it has oil pressure, which is as soon as the crank turns at all, the tensioner is even more tight.

If you ever take the timing cover off, just spend a few minutes spinnibng that crank pulley around and you'll see how all this works. It's pretty cool. I am a real nerd so I find this entertaining.

Oh, and YEAH setting valves at full heat takes somebody that likes their finger a LOT less than me. It would be alot easier if they'd publish the intended spacin gat DEAD COLD, eh?

cperry said:
yes it is possible to do it without pulling head, put you disrupt the head gasket and oil usually leaks at the cover.Scheduled maintance i believe is every 100k.
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And I still do not see how the head is the least bit disrpted in changing all the timing components. You can leave all head bolts in place, only one that is even related to the head is the Mystery Bolt and that only goes into the TC and not the block?
Toyota makes no mention of the timing chain as a maintanance service part, like timing belts are for many cars. The plastic guides wear out long before the chain itself does (assuming you change oil like you should).
 
Ya i was talking about slack in the chain when vehicle is not running and when it first starts up on driver side. If the chain is stretched badly but still in time then the distance from cam to crank stays the same but the chain is now longer. on passnger side the adjuster is absorbing the extra length, but on driver side there is nothing to take up the slack just the guide to guide it. This is my own rational and i could be wrong so feel free to tell me if i am.

The head gasket seals to t-cover and one is supposed to put a little RTV at the piont were block,t-chain, and head all meet. this is the part of gasket that gets disrubted and then usually leaks.

I don't know if toyota really recomends timing chain all i am saying is the plastic guides only last a 100k if that. but i do know that they say pull the head to do it. And i have seen alot of 22re's leaking oil from the t-cover at the head and i think this is b/c mechanics can do the job so much faster and still charge same rate as pulling the head. Maybe i am just an ass and should stop pulling the head but it seems to be the right thing to do, and the end result is better quality.
 
RatLabGuy said:
As I said, do you have some reason to believe the oil pressure is low, or anything like that - or is it simply that you pulled the valve cover off just for the hell of it and check on those guides, saw a little bit of slack in the chain?
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just like you said, i wanted to give the guides a once over and noticed slack in the chain...and wanted to figure out what was going on before i went any further. i'm starting to feel less and less like i even have a problem there. but the oil pressure thing was just under the theory that the tensioner might not be operating optimally due to low oil pressure.

another :beer: for everyone for being real kick @$$ about this with me
 
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