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Discussion Starter #1
Started working at 10pm and putted everything back at 3am in the morning. We wasted 3 hours trying to figure how to put the chain tensioner back in the car and later found out there was a mechanism to compress it. doh! Tried to start the car and it won't start. Wonder what went wrong. Got to redo it again tonight.

Btw, I measured the lobes on the 91intake cam to be 38.5mm and the lobes on my 99 to be 37.8mm. Does a difference of less than 1mm really makes that much difference? Well but at least I think the 91s have a longer duration.
 

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70/30 Racing
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your cam timing is off.

thats going to be fun to reset. be prepared to waste more time, sorry to hear that.

did you zip tie the cam gear on? did you make sure it was at TDC?
 

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Discussion Starter #3
I did zip tie it. Although one zip tie broke but I don't think it slip though. It was near top dead center but not exactly. We set the car in 5th gear and pushed it till it was near tdc. However, I think there's no point of setting it to TDC if all I'm doing is the intake cam. How would I know if my cam timing is off and how would I reset it?
 

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it's an se-l..not an se-R
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the cam sprockets should be at 10 and 12 at TDC. manually rotate the crank and set it to TDC.

if you don't know where TDC is, get a hanger. remove the #1 spark plug. put the hanger inside the #1 cylinder. manually rotate the crank until the hanger reaches it's highest piont. that would be TDC. after that, make sure the intake cam is at 12 o'clock and exhaust cam is at 10 o'clock. then count 20 rollers between the sprockets. the chain between the intake and exhaust sprocket should be snug and not loose.
 

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it's an se-l..not an se-R
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this is what i mean about 10 and 12 when the #1 piston is at TDC.
 

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70/30 Racing
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basically, make sure the timing mark is at 0* on the crank pulley. then, youre gonna have to reset the cams so that the pins are at 10 and 12 (or the lobes face away from each other on the #1 cyl)

there should be 11 links between the 2 pins on the sprocket. this is BETWEEN. so, since the mark will end up on a link that is on the outside (viewed from above) count the inside links until you get to the link that is on the exhaust cam mark. there should be 11.
 

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99SE-L said:
I did zip tie it. Although one zip tie broke but I don't think it slip though. It was near top dead center but not exactly. We set the car in 5th gear and pushed it till it was near tdc.

If it broke, it probably slipped. Believe me, it's happened to me a couple times. Next time, use two zip ties on each gear.

Also, you don't have to roll the car to turn the crank. Just get a socket on the end of the crank and turn it until it's at the position you want.
 

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Discussion Starter #8
Wow, thanks for the input guys.

I don't understand why it's necessary to set it to TDC for an intake cam only installation. And I don't think there is enough clearance to stick a socket in to turn the crank unless I take off the wheel which makes pushing the car easier.
 

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it's an se-l..not an se-R
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you don't have to set it at TDC for a simple intake cam install. we're telling you to set it at TDC so you can determine if you have the cams set correctly or skipped a tooth. i've been through this headache before so just take our advice.
count the rollers, count the links, whatever. it's simple if you just take our advice. when i installed my s4's, my intake and exhaust cam were both off one tooth cuz i lost my zip ties. it wouldn't start. i set it again and it started up fine and idled fine, but it ran real slow. turned out the intake cam was off one tooth. then with the help of a couple of forum members, i had the prblem fixed and felt the benifits of s4's.
 

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99SE-L said:
Wow, thanks for the input guys.

I don't understand why it's necessary to set it to TDC for an intake cam only installation. And I don't think there is enough clearance to stick a socket in to turn the crank unless I take off the wheel which makes pushing the car easier.
makes the install foible proof. if you **** up, it isnt hard to get it back.

you dont need to take the wheel off. all you need to do is jack up the car, and turn the wheel all the way right. PLENTY of room.
 

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Yes Dear.
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hehe this happened to me.. but my car started and i was off.. ran so slow i couldnt keep up with a dx.. doh!!
 

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That sux, hope for the best. This is one of the reasons im gettin my turbo put in my professionals.
 

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Or at least get someone to help you who has experience with the install. That's what I did, and I'm glad I only spent 4 hours on my first cam install!

Justin
 

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Discussion Starter #14
I found out that exhaust cam mark was off the colored link by one tooth. I think it slipped when I did it last time. However the intake cam was off by 3 teeth and I swear it didn't slip because the tie strap was in place. Last time the dealer did the chain for me when I blew the head so they could have messed it up. But my compression was at 200psi for all 4 cylinders. However my trap speed was only 87mph. How much horsepower would a tooth cause.

Now the big problem is after I realigned the chain with the sprocket and tightened everything back on. I couldn't turn the engine anymore. I'm wondering if the chain might have gotten jammed somewhere at the bottom. Does the crank sprocket have enough slack for the chain to slip? I don't dare crank the engine for fear that it might break the chain and break all the valves. Please give me some advice on this one guys.
 

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there is extra chain on the intake side of the engine. DO NOT force it, or you will end up removing the timing cover to replace the oil pump.

the way i did it, once it got ****ed up this far, is i kept turning the engine with a friend holding the chain up so it didnt get bunched up (basically, all he had to do was hold the chain up so it was tight) until i could see both timing marks, and they would line up with the timing marks easily with the engine at TDC. put the cams at the proper orientation (12 o clock for the exhaust, 10 for the intake cam) and it will either line up easily or it wont, as one tooth off on the crank sprocket is like 3-5 (i forgot, but it ends up WAY off) on the timing sprockets. if it doesnt line up, keep turning the engine until both timing marks are visible and it is at TDC again. if it moves farther away from spot on, turn it the other way.

youre gonna be there for a while, there are 72 possible combinations, sorry!
 

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Discussion Starter #16
The timing marks on both the exhaust cam and intake cam are aligned and clearly visible. I put back on the timing chain tensioner too so it is tight. I lifted the chain off of the exhaust sprocket and turned the exhaust cam to align the marks. And since the intake sprocket was off, aligned it was easy. But now even with the timing chain tensioner on, the part of the chain going from the exhaust sprocket to crank sprocket is slightly loose. Is it's possible for the chain to slip on the crank sprocket without taking off the bottom timing chain cover.
 

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you cant possible get them on wrong. if you turn it enough times, it will hit every single one of those marks.

you have to turn it until it ends up meeting the following requirements:

1. the two links on top match up perfectly with the cams at 10 and 12.
2. the engine is at TDC.

if it doesnt meet this criteria, take the cam sprockets off the chain and out of the engine, loosen the cams all the way (so the valves arent stuck down while the engine tries to turn), and hold the chain up tight (basically, pull straight up in relation to the engine until there is no slack and hold it that way) while you turn the engine until the marks are visible again and the engine is at top dead center. try the cam gears again with the cams still at 10 and 12 and if they have moved farther away from correct, turn the engine the other way until this happens again.

repeat until the timing is correct. you may end up turning the chain all the way around 72 times before this is right.

got it?
 

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Discussion Starter #20
I spent another whole day and found out that the engine will not turn when I have both the intake and exhaust cam markings aligned to the colored link. They are at 10 and 12 and TDC. It will turn if there is 19 points inbetween but not if there's 20. Could it be that the crank sprocket mark is not aligned to the yellow link which cause it to be stuck. I'm guessing it gets stuck because the pistons are hitting the valves.
 
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