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Discussion Starter #21
SO far this is what has been done:

Verified @ TDC (lobes facing away from eachother & 2nd mark (from the left) on crank pulley): That the chain between the Exhaust cam sprocket and crank is tense, that there are (moved the intake cam sprocket one over...was 21 pins) 20 pins between the 2 dots, dowel pins on the cam sprockets are @ 10 o'clock (intake) 12 o'clock (exhaust). Before moving the intake cam sprocket, I had the distributor set in the middle and it read 15 degrees on the crank pulley, so I am assuming that it should still be @ 15 degrees?

From my understanding, the distributor timing is running off the exhaust cam. So, if I were to move the intake cam the distributor timing should not be affected? I have read in other threads that after installing S3s some cars ran rough for a while, maybe I should let it run for a week or so. Also, I was wondering if anyone would remember or take a look at their cam lobe orientation on cylinder #1 @ TDC. @ TDC both lobes are facing away from eachother, but the intake cam lobe is facing slightly upwards and the exhaust cam lobe is slightly facing downwards, does that sound about correct? ALL INFO is greatly appreciated.
Thanks,
KEN
 

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you might have it right, i don't have a pic of mine but you might want to try it for a week. you are right, i can't really tell if your problem is just the comp needing to adjust or the timing being off. the reason i ask about the dist position is that if your timing is off, you will need to advance the dist. almost all the way to read 15* on the crank pully. hit your car with a timing light, thats where you will find your answer. if the dist. is in the middle, and reading 15* then you timing is correct. if not you have a mech. timing issue still.
 

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TRUSE-R said:
Isn't it supposed to be 21 links (2 pins within a link, correct) & 20 pins? People have stated to count the pins (20) and not the links 21 as shown on the JWT instructions. Currently I have it with 21 pins! When you say to try it @ 19 pins...so I move the intake or exhaust cam???? The distributor is in the middle! You guys have been a great help.... All info is greatly appreciated.
Thanks,
KEN

by the timing i meant the ignition timing set by the distributor. you should really verify that it is correct, not just assume it is. and as far as the links go, the mark on the intake cam sprocket should be on the 20th space inbetween the pins over from the exhaust cam. so if you were to mave the chain 1 link at a time 20 times, that is where the intake cam sprocket should be in relation to the exhaust cam sprocket. i really wouldn't just move one cam at a time unless you have a real good idea of what you are doing (not trying doubt your skills or anything, it is just easy to make mistakes here). i would do them both over again, starting with the exhaust cam and pulling up all the tension from it again, and making sure that when you put the chain on it that the dowl pin is at 12 oclock.
 

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Could someone please clarify how the cam lobes for cylinder 1 should be oriented? People say facing "opposite each other", but does that mean 180 degrees opposite each other (like two rain drops pointing sideways), or is it that the top of both lobes should be horizontal and the narrowest parts of the lobe facing 10 o'clock (intake) and 2 o'clock (exhaust)? Think of two rain drops falling inward at a 45 degree angle.
I have read threads where a person says "opposite each other", but I read another thread in which the fellow says the narrow part of lobes will point to 10 and 2 o'clock when all is correctly positioned and timing is right.
Please clarify.
 

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Could someone please clarify how the cam lobes for cylinder 1 should be oriented? People say facing "opposite each other", but does that mean 180 degrees opposite each other (like two rain drops pointing sideways), or is it that the top of both lobes should be horizontal and the narrowest parts of the lobe facing 10 o'clock (intake) and 2 o'clock (exhaust)? Think of two rain drops falling inward at a 45 degree angle.
I have read threads where a person says "opposite each other", but I read another thread in which the fellow says the narrow part of lobes will point to 10 and 2 o'clock when all is correctly positioned and timing is right.
Please clarify.
1959

just like that. 5 links to the cam gear notch on the intake (left side) .20 links between the two cam gear notches. 9 links (the 9th one is a bit below the head rockercover level) on the exhaust (right)
 

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OUTSTANDING! This is a huge help, I Thank you! Almost everyone that makes a video with their valve cover off pointing to the cams and the sprockets at Top Dead Center never lingers long enough on the cam lobes to get a good, clear view of their orientation. Thank you very much. I definitely appreciate it. Where did you find this diagram, by the way?
 

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Could you please let me know something else? I have been looking and looking and can not find the answer to this question. Because the timing chain is not a "serviceable" part, I am unable to find this answer in the FSM. Here is my question: When the timing chain tensioner is extended and putting tension on the slack side guide, should there be any slack in the chain, in the section between the two cam sprockets? I have not run the engine yet. I had to reset the chain, as it had skipped a tooth when I was installing the new tensioner. Will oil pressure affect the amount of pressure that the tensioner exerts on the chain guide? (It is a mechanical, ratcheting-type of tensioner, so I have been under the impression that the oil pressure doesn't affect the force exerted by the tensioner.)
 

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Isn't it supposed to be 21 links (2 pins within a link, correct) & 20 pins? People have stated to count the pins (20) and not the links 21 as shown on the JWT instructions. Currently I have it with 21 pins! When you say to try it @ 19 pins...so I move the intake or exhaust cam???? The distributor is in the middle! You guys have been a great help.... All info is greatly appreciated.
Thanks,
KEN
There is a total of 11 LINKS involved in order to create 20 pins between the two sprocket marks.
9 links in between the marks with the additional 2 links at the ends "straddling" the two marks on the cam sprockets.
1 link = 2 pins
9 links = 18 pins
2 links = 4 pins, However, only the inner pins of these 4 are added to the 18 in order to give a total of
20 pins between the sprocket marks.
Example: (o-X-o) (o-o)(o-o)(o-o)(o-o)(o-o)(o-o)(o-o)(o-o)(o-o)(o-X-o)

  • (o-X-o) and (o-X-o) are the outermost links of the 11 links involved in creating 20 pins.
  • X represents the marks on the cam sprockets. Between theses marks there should be 9 links (18 pins).
  • The underlined o's are the outermost pins of the 20 total pins that should appear within the two sprocket marks.
9 links (18 pins) between the outermost 2 links, plus the two inner pins on the outermost links beyond these nine. Because there are 2 inner pins to add to the 18 pins, in total there are 20 pins between the marks on the cam sprockets.
Also, See Post #27:
I also found it helpful to refer to the number of sprocket teeth that appear at head-lip level or above on the sprocket, as the count approaches the sprocket marks, starting at the head lip. Counting this way, confirms a total of 20 pins between the sprocket marks.
  • "5 teeth and a valley" on the Intake sprocket, "9 teeth, even" on the Exhaust sprocket.
 

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Why do I have slack in the chain between the two cam sprockets when the crank pulley is approaching TDC from 1/4 turn before TDC until 1/4 turn after TDC, AND at the same points for Bottom Dead Center?
When I crank the pulley, the slack goes away, until it is at the range I mentioned, for both TDC and BDC. I noticed beginning at 19:45min there is a little slack at two separate occasions while the fellow rotates the crank manually. 19:45 min SLACK IN CHAIN WITH TENSIONER EXTENDED
I have 20 pins between the sprockets. 5 teeth on the intake sprocket from the head to the mark on the intake sprocket, and 9 teeth from the head to the mark on the exhaust cam sprocket.
I noticed the slack side chain guide had a lot of play in it, when I was setting the chain on the sprockets. Is it supposed to be able to rock in and out when the chain is not riding on it? In and Out, as in towards the passenger side and towards the driver side, not to the firewall and bumper. I wonder if the bolt that secures it in place is loose.
 

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Why do I have slack in the chain between the two cam sprockets when the crank pulley is approaching TDC from 1/4 turn before TDC until 1/4 turn after TDC, AND at the same points for Bottom Dead Center?
When I crank the pulley, the slack goes away, until it is at the range I mentioned, for both TDC and BDC. I noticed beginning at 19:45min there is a little slack at two separate occasions while the fellow rotates the crank manually. 19:45 min SLACK IN CHAIN WITH TENSIONER EXTENDED
I have 20 pins between the sprockets. 5 teeth on the intake sprocket from the head to the mark on the intake sprocket, and 9 teeth from the head to the mark on the exhaust cam sprocket.
I noticed the slack side chain guide had a lot of play in it, when I was setting the chain on the sprockets. Is it supposed to be able to rock in and out when the chain is not riding on it? In and Out, as in towards the passenger side and towards the driver side, not to the firewall and bumper. I wonder if the bolt that secures it in place is loose.
some slack is fine.the oem tensioner is oil pressure activated if you put a ruler vertically between the the top cam gears, you should be able to get 5-6mm of upward chain movement between the top gears by pushing up the chain
 

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Thank you for your information. I sincerely appreciate it. Do yo mean to say that because the tensioner is oil-pressure activated, only after I run the engine will there be 5-6mm of upward movement on the chain? Because currently I can make the chain touch the upper guide, pressing upward between the two cam sprockets.
I will probably remove the upper guide altogether, but I want the tension in the chain to be correct.
Currently, I have NOT started the engine, as the oil pan and valve cover are still off.
The timing chain tensioner's plunger is extended and exerting pressure onto the slack-side chain guide, and there is more than 6mm of slack in the chain with the tensioner is extended.
 

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Thank you for your information. I sincerely appreciate it. Do yo mean to say that because the tensioner is oil-pressure activated, only after I run the engine will there be 5-6mm of upward movement on the chain? Because currently I can make the chain touch the upper guide, pressing upward between the two cam sprockets.
I will probably remove the upper guide altogether, but I want the tension in the chain to be correct.
Currently, I have NOT started the engine, as the oil pan and valve cover are still off.
The timing chain tensioner's plunger is extended and exerting pressure onto the slack-side chain guide, and there is more than 6mm of slack in the chain with the tensioner is extended.
yeah, its pretty much it. there are solid type tensioners (mazworx/taarks) who run on 6mm play. obviously theres more in an adjustable type with no oil pressure, so sorry if that last post was misleading.all i wanted to say was there is quite a bit of play there.
 

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Alright, Good information. Very insightful and relevant. Having the tensioner in place and extended was making me expect to see no slack in the chain, at any point. But you are saying that the oil pressure creates even more pressure to be exerted onto the chain guide, thereby eliminating all but 5 - 6mm of vertical movement if one pushes up on the chain between the two sprockets. That is very helpful information.
There is currently enough slack in the chain that when pushing upwards on it, it easily touches the upper guide. This extra slack makes me concerned the chain could jump a sprocket tooth upon start-up. What do you think?

I noticed on my old (failed) tensioner that the "ratcheting device" no longer has the little piston that pushes upon the little lever that engages on the teeth of the plunger. There is no tension at all on that little lever because the piece (mini piston) is gone. Do you know what causes that piece to fall out or wear out?
 

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get rid of upper guide,motor dont need it, if you use the new style tensioner to replace your old one. chain jump is very common, but not off the bottom sprocket, always the cam gears, mainly exhaust.
 

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Ah, ok. I was wondering how necessary it was. I read that it is there to keep the chain from hitting the valve cover if the tensioner fails. That would be a lot of slack in the chain for it to be able to make contact with the valve cover.
 

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Ah, ok. I was wondering how necessary it was. I read that it is there to keep the chain from hitting the valve cover if the tensioner fails. That would be a lot of slack in the chain for it to be able to make contact with the valve cover.
new tensioner, and you wont have that problem, but yeah, thats what its for.
 

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I have replaced the old style, stock tensioner with the updated style, stock tensioner, seen here stock tensioner part number 13070-2J203 . I just have not cranked up the engine yet and am seeing a considerable amount of slack between the two cam sprockets, which made me wonder if that slack should be there, at all.
Were you saying that with this style tensioner, there won't be any slack in the chain once there is oil pressure? Or were you referring to a Mazworx manually adjustable tensioner?
 

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I have replaced the old style, stock tensioner with the updated style, stock tensioner, seen here stock tensioner part number 13070-2J203 . I just have not cranked up the engine yet and am seeing a considerable amount of slack between the two cam sprockets, which made me wonder if that slack should be there, at all.
Were you saying that with this style tensioner, there won't be any slack in the chain once there is oil pressure? Or were you referring to a Mazworx manually adjustable tensioner?
It's normal to see a lot of slack in the chain when the motor is not going. once going, the oil pressure builds, and the tensioner reduces the amount of play. something like the mazworx or taarks tensioners have a manual ( not oil pressure ) adjustment. once too the right tension, these manual tensioners should have at least 6mm upward play between the cam gears ( as a reference ). to reduce this figure is at your peril, because at idle or commuting around, the chain can contact the nylon chain guides, and debris of this can* end up in the sump pickup.
 
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