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Discussion Starter #1
Ok, from my previous post
http://www.sr20forum.com/showthread.php?t=115231&highlight=timing+chain+slack

I decided to go back and redo everything, well I did and still have this problem. I took the front cover off lined up the gold link with the crank sprocket and lined up my 2 black links wiht the cam sprockets. The dowel pins sit at about 10 and 12 but there is slack in the chain at tdc and bdc. There is enough slack in the chain at tdc with the chain tensioner in that i can lift the chain and hit the timing chain guide thats above it without any problem at all. I need help and need to kknow if this is normal. Mcoy told me in that post he had similiar problem and just ignored it but i cant afford for anything to happen to this motor. There is enough slack in the chain that when you hand crank the motor over, the exhaust cam will move a little bit before the intake cam does. Im giving up and dont know what to do about all this, i dont remember it being this loose when i took the motor apart.

anybody please help
 

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Is this a New Chain?
 

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B14 Se-Rious said:
Ok, from my previous post
http://www.sr20forum.com/showthread.php?t=115231&highlight=timing+chain+slack

I decided to go back and redo everything, well I did and still have this problem. I took the front cover off lined up the gold link with the crank sprocket and lined up my 2 black links wiht the cam sprockets. The dowel pins sit at about 10 and 12 but there is slack in the chain at tdc and bdc. There is enough slack in the chain at tdc with the chain tensioner in that i can lift the chain and hit the timing chain guide thats above it without any problem at all. I need help and need to kknow if this is normal. Mcoy told me in that post he had similiar problem and just ignored it but i cant afford for anything to happen to this motor. There is enough slack in the chain that when you hand crank the motor over, the exhaust cam will move a little bit before the intake cam does. Im giving up and dont know what to do about all this, i dont remember it being this loose when i took the motor apart.

anybody please help

OK with the tensioner in and everything bolted up have you rotated the motor by hand? Try rotating all the way around back to #1 TDC on the compression stroke and it should be all good. The tension is a bit different when installing everything but once it is rotated it should be fine...
 

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Discussion Starter #4
The chain isnt new, when I did have it installed I cranked it over around at least 3 times, the slack was still present at tdc nd bdc. Im out of ideas and am ready to drop the motor off at a shop for them to check it out. The slack is more than enough for both the intake and the exhaust sprocket to skip teeth. Right now im in school and my school year ends in 1week, i have 3 days to work on the motor. As of now, i have the black links lined up with the cam sprockets and the gold link lined up with the crank sprokect w/ the chain tension NOT in.

But wes, i tried that before and still dindt get any better results, any other ideas?
 

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When you installed the tensioner did you press it in and hook the clasp to hold it in the "in" position? If so did you remember to unhook it and put tension on the chain once it was installed?

I'd find it hard to believe the chain would/could get that stretched out...
 

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Discussion Starter #6
I did put the hook on the pin on the tensioner, throw it in and saw very very little slack go away, maybe 1/8". Then I hand cranked the motor around maybe3-4 or times, i kno at least 2 times. And the slack was still present at tdc and btc. The slack was enough to hit the upper timing chain guide (if it was still there i tossed it but test fitted it to see how bad the slack is).
 

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I was going to say the same thing... Is the tensioner bad? You can see it extend out once the clasp is unhooked!
 

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wes said:
I was going to say the same thing... Is the tensioner bad? You can see it extend out once the clasp is unhooked!
I am sure the tensioner is not the issue here. I noticed the same thing last month while installing the W11 motor in my car. As I mentioned in his last thead, I compared the Avenir to the stock motor... they both had slack in the chain (only between the sprockets) at TDC and BDC. The biggest things was that the Avenir had alot more slack than the stock motor did.

Everything was right on the motor... we double and triple checked everything that was touched during the tear down and rebuild of the motor. We took a chance and started it since we couldn't find anything wrong...

Since getting the car running I have logged over 2000 miles with 600 of those being on the track. I get no clanking or chain slap on startup... which would indicate a tensioner problem. The car has ran fine... leading me to believe that what I was seeing was probably related to the motor sitting for a while.
 

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I also have the same slack between the cam sprockets at (TDC and BDC) and can press the chain upward to the point that it hits the upper guide. (I will get rid of the upper guide, but for the sake of eliminating factors that might contribute to unnecessary chain slack i the future , I want to replace the guides and their bolts, but I saw this same slack between the cam sprockets and wondered if it was normal given the tensioner is a hydraulic tensioner and there was currently no oil pressure in the engine.
I called jimwolftechnologies and a "technician" told me this slack is normal and that the oil pressure will cause the tensioner to extend and push more on the slack-side guide once the engine is running. He also suggested before cranking the engine, to pull the fuel filter fuse and than crank the engine. This way just the stater is moving the engine without any real rpms or combustion behind the pistons. He said to do this until the oil pressure light on the dash goes away.

After replacing the tensioner, I removed the chain preparing to replace the older guides with the later guides. (I am aware that in the later SR20's, Nissan changed the guide and the bolt, which make think it was for some specific reason.), but when I look at the slack-side guide (the curved one), I see that the guide moves laterally on the bolt (1/8 inch) and it seems concerning.
Front to back is to be expected, but there is also horizontal movement at the pivot bolt. I am thinking this extra movement may have put more stress on the tensioner and caused it to fail. Not really sure about that, which is why I wanted to ask here. LOOSE SLACK-SIDE CHAIN GUIDE, WRONG BOLT (the first three minutes).
I've tried to loosen this bolt, but it will not turn at all, loosen or tighten. Somehow, the Allen hole became rounded out, previously, so I pounded a 1/4 inch bit into the bolt's rounded-out Allen hex and used an impact driver to try to loosen the bolt but was unsuccessful.
The bit does not spin or move at all when I attempt to loosen the bolt, which is good, but the bolt won't budge.
Anyone run into this bolt not wanting to budge?

Should I be concerned about the horizontal movement (1/8 in.) of the slack-side guide on its pivot bolt?
 
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