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SE. Period.
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323 Posts
Discussion Starter #1 (Edited)
OK I am going to clean up this post for clarity.
If you want to make things easy on yourself when putting cams back in the motor, ensure the Crank is at TDC by checking the position of the #1 cylinder piston with a long screwdriver/thin metal rod, and looking at the crank pulley. Don't mistake the very first mark for TDC or 0*. It goes (for a B14, 98 specifically):

|..........|..........|...........|.....|....|..........|
-5........0..........5..........10...13...15........20

you want it at 0. If its not at zero, it will be tough to install cams as you work against the valve springs. It gets a lot easier at TDC (the cam probably wont fall right in, don't force it cuz you're just compressing valve springs and not accomplishing anything, just torque it down, using fingers at first, veeeeery carefully. Then check for the cam being able to rotate around.

About tools, for cam swaps you will need both a 1" and 1-1/16" wrench. Sometimes the cam hex lines up for one wrench, sometimes for the other, or it felt like one cam would use one wrench, while the other was different. I dunno, but get both. Also, make sure the wrenches aren't too wide, I ran into this problem and it sucks. Try them out on the cam hex if you can.
Deep well 10 and 12mm sockets are fun to have, but a 2" extension or whatever can make up for it.
27mm socket for turning the crank.
24mm shallow socket for the cam sprocket bolts. Otherwise, you wont't be able to fit around the coolant hose or the power steering resevoir.
Get a light if you plan to work into the night.
A bendy socket wrench or a bendy open wrench helps for the timing chain tensioner, or stuff in general.
Patience is the best tool to have. If that doesn't work, I guess you can always get a sawzall...

OK, onto the problem now. The cam timing is off. I need to get it perfect again. Hopefully I can do this without taking the front cover off, essentially requiring dropping the motor, but if it comes to that, o well.

Here's a recap of the key points:
- tensioner out
- cam sprockets off cams
- cam swapped, first at -5*, then really at TDC
- sprockets fell into motor at some point, thought i skipped a tooth on the crank sprocket (apparently impossible)
- rotated crank around until TDC reached, chain links in an unknown position
- exhaust cam dowel set to 12:00, intake set to 10:00 (cam lobes point out)
- chain laid back on sprockets, seemed a bit off, sprockets both moved one roller clockwise to line up the dowel pins even more at 10 and 12.
- torqued cam sprockets back on
- confirmed TDC w/ radio antenna in place of screwdriver
- installed tensioner
- when I rotate the crank to about 40* CW or CCW, I can't rotate the crank anymore. Hypothesis: valves are hitting pistons.

Current plans of action:
(evilsr20degg)
- take sprockets and cams out
- rotate chain again until the silver/black colored-marked-mating links are about in the relative right position (up top by mating marks for sprockets, around 10 and 12 I guess) when the crank is at TDC.
- put sprockets on chain, hang them up.
- install cams, bolt on sprockets
- test again by rotating the crank
- if it rotates fully, check to make sure the cams return to the same position every 2 revolutions of the crank

(worst case scenario)
- Take off front cover. Line up chain by hand.
Do this either by the FSM instructions, leaving the engine in the car, or by dropping the engine out.
 

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Premium Member
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9,405 Posts
My brain hurts from all that. Josh just called me and explained what is going on. My advice:

Remove both cams from the engine. Turn the crank until the TDC mark on the pulley is lined up with the indicator on the front cover. Hold the chain to get some tension on it. Don't worry about the colored links on the chain. Those mean nothing, unless you have the head off and the front cover off. Those line up once every 1000 turns or something. With the crank pulley showing TDC, install the exhaust cam with the dowell at 12:00. Count back 20 rollers, and install the intake cam gear. There should be 20 rollers between the indention on the gear, not the dowell pin. Mark the chain with white out, or s paint pin, so you can see of the chain jumps when you are torquing down the cam gears. Also put a zip tie or 2 on the gears to hold the chain.

I wouldn't try to install the cams any other way, other than that. The motor needs to be at TDC anytime you mess with the chain, otherwise you can seriously screw the motor up. Also make sure you turn the motor by hand, not with the starter, to release the hook on the tensioner.
 

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SE. Period.
Joined
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323 Posts
Discussion Starter #3
the tensioner is out
I have just successfully (and extreeeemely slowly) installed the intake cam. That part no longer needs help, because I think I can do it again without snapping things. Uh, is it ok if I go intake then exhaust? Should I install the cam sprockets on both, or one then the other? Should I take off the intake and start with the exhaust cam? Does it matter if they're not hooked up in the sprockets, but in the right (around 12 o clock, with lobes pointing out) position?
Also, the sprockets are zip-tied to the chain, just so you know. They havent moved, just the crank gear sprocket might've, to clarify. Ok, I'm going to pick up the bolts (for the exhaust cam, that's why i started with the intake) and a better fitting 1-1/16th open end wrench, and then check back.
 

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Premium Member
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9,405 Posts
I standby what I posted. Anything else, and you are on your own. If you called me to come help you fix that cam install, my post is exactly what I would do. Right now, you have no way of knowing if everything is lined up correct, or not. you asked for help, and I gave it. If you don't want to listen, that's fine with me.
 

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Rattle Box
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360 Posts
iMagnusX said:
That part no longer needs help, because I think I can do it again without snapping things.
What did u snap? Cam install is a delicut process, nothing should be snapping. The only force applied anywhere should be the valve springs in which a lobe lands on.
 

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SE. Period.
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323 Posts
Discussion Starter #8 (Edited)
http://www.sr20forum.com/showthread.php?t=160371 is what i broke.

Eric, I mean, will the intake camshaft being there not connected to the cam sprocket affect the timing, or crank, or anything that I need to worry about?

OK, i just checked, and the rollers, as in, each little pin that goes through a link, OKK.... if I start on the one just to the right of the left, intake "indentation" or "mating mark" I reach the pin just left of the right, exhaust mating mark in 20 pins.
Again, pin right of intake mark + 20 pins counted to right = pin left of exhaust mark.
A Pic to sorta clarify:



again, take the intake cam out?

Is there a number I can call you at?
 

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Deviled Egg!
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6,321 Posts
I asked you not to quote me... lol
Me said:
... but don't quote me
:rofl: You still quoted me...

I didn't think you would take our convo and post it for the world to see... baahhhh.. but you're super paranoid right now... :)

The point is... you should have taken your time when doing the cam install... otherwise you wouldn't have even messed with the exhaust cam at all and snapped that bolt. That aside and in the past...

just calm down...

your in a little bit of a mess right now, but try and use the help that eric and I gave, more so eric because he is more knowledgable than I am.

Re-read what is there... look at the FSM again... and do it to it... Your going nuts and don't realize the answer is in front of you...

And read the torque specs thoroughly before you turn a wrench that way you won't snap anything... reading too fast will cause you to find that out the hard way again... :(

You will be fine... just take your time...
 

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Premium Member
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iMagnusX said:
http://www.sr20forum.com/showthread.php?t=160371 is what i broke.

Eric, I mean, will the intake camshaft being there not connected to the cam sprocket affect the timing, or crank, or anything that I need to worry about?

OK, i just checked, and the rollers, as in, each little pin that goes through a link, OKK.... if I start on the one just to the right of the left, intake "indentation" or "mating mark" I reach the pin just left of the right, exhaust mating mark in 20 pins.
Again, pin right of intake mark + 20 pins counted to right = pin left of exhaust mark.
A Pic to sorta clarify:



again, take the intake cam out?

Is there a number I can call you at?
If you leave the cam in and turn the motor without the gear, you won't get too far. The cam is opening at least 2 valves, and one of the pistons will come up and hit them. At this point, you need to remove both cams, and put the motor at TDC. The reason you broke a bolt, is because you had too much tension on the cam. I've done coutless cam installs, and I have never broken one of those bolts.
 

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SE. Period.
Joined
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323 Posts
Discussion Starter #11
OK I'm gonna get up maybe like 6:30, 7 AM central time and try to finish this thing out. If you're up that early, call me. OR when you do get up (say, before 10 am cuz that's when i gotta work) call. I'll be back at way late tonight. call anytime, but i might have to hang up if its in the early evening tonight.

uh, intake is still in, exhaust is halfway in because i hadn't read that last post yet. talk to josh, i called him. I gotta run.
 

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Professor Dingbat
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5,543 Posts
1. It is impossible for the timing chain to fall off the bottom sprocket.

Did you zip tie the gears to the chain or paint mark them?

Install the cams as if the motor were at TDC, then rotate them the half turn so that they line up with the cam gears. Both lobes on cyl #1 should be pointing outwards (intake at firewall, exhaust towards rad) and both should be pointing slightly up. maybe 45° or so from vertical. Tighten them half turn at a time and they will 'find' the spot where none of the valves are open.

Eric, I mean, will the intake camshaft being there not connected to the cam sprocket affect the timing, or crank, or anything that I need to worry about?

OK, i just checked, and the rollers, as in, each little pin that goes through a link, OKK.... if I start on the one just to the right of the left, intake "indentation" or "mating mark" I reach the pin just left of the right, exhaust mating mark in 20 pins.
Again, pin right of intake mark + 20 pins counted to right = pin left of exhaust mark.
A Pic to sorta clarify:
I would recommend against this method. You really must paint mark the gears to the chain or zip tie them. I have installed 10+ sets of cams on an SR20 and the dots never line up to exactly 10 and 12 when the needle is lined up with the TDC mark on the pulley. The only way I feel confident setting the cams up like this is if the timing chain cover is off and you can verify that the marks line up on all 3 sprockets.
 

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Professor Dingbat
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5,543 Posts
Right now, you have no way of knowing if everything is lined up correct, or not
The cam gears are zip tied to the chain. As long as they stay this way (or you paint mark them and put them back exactly as they were) you CANNOTT screw the timing up.
 

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Deviled Egg!
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6,321 Posts
FastNX said:
1. It is impossible for the timing chain to fall off the bottom sprocket.
I'm not contradicting your statements as I'm sure you understand the SR20 more than I, but...

1) How can the timing chain not fall off of the timing chain sprocket with the tensioner removed and a the cam gear hanging loose w/o a cam bolted in it (aka slack in the chain)? I know there is a guide preventing lateral movement, but I'm confused?
2) If the timing chain cannot fall off of the bottom sprocket then how does this explain people jumping teeth on the chain before startup?
3) Why is preventing slack in the chain such a practiced procedure if this is the case?

LMK, Peace...
 

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Professor Dingbat
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5,543 Posts
There timing chain cover fits around the outside of the chain. The chain will run into this cover before it can slip off the gear. This information from JWT.

You post is long and confusing. Can you please direct me to the part about the timing being off.
 

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Registered
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613 Posts
Oh damn, I am not getting into this!

:::::::Turns and runs away:::::::::
 

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Deviled Egg!
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6,321 Posts
FastNX said:
There timing chain cover fits around the outside of the chain. The chain will run into this cover before it can slip off the gear. This information from JWT.
I never knew that... that is very interesting... Thank You


FastNX said:
You post is long and confusing. Can you please direct me to the part about the timing being off.
The only knowledge of the timing being off was from me reading second hand on the forum and other SR20 representative places, but, this still doesn't explain why preventing slack in the chain during cam related work is necessary? Am I just misinformed?
 

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Professor Dingbat
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5,543 Posts
By putting the timing chain block in, you are not preventing slack. You are avoiding having to remove and replace the timing chain tensionner. According to the FSM, you are supposed to remove the timing chain tensionner when you remove the cams. I guess JWT figured it easier to shove a block of wood down there to hold the tensionner back. Saves some time, and eliminates the chance of skipping teeth if you improperly install the tensionner (start it before releasing it)
 

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Deviled Egg!
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6,321 Posts
I see... thanks for sharing that info... good stuff... PMed
 
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