Timing Chain Skipped

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huntin5L
Posts: 256
Joined: Sun Dec 22, 2002 8:45 am

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Help!!
Modified by huntin5L at 12:29 AM 5/7/2007


huntin5L
Posts: 256
Joined: Sun Dec 22, 2002 8:45 am

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Okay here are my questions in detail. I set the motor to tdc, which if you look at the timing mark it is at the first mark, let me know if im right. Now when i took the distributor cap off the red mark you see is where the #1 plug is and the rotor doesn't look like it lines up exactly, let me know if that is okay. I tried taking the distributor out to line up the rotor to the red mark, but it only seems to fit that one way. Another thing is if the chain jumped does that mean my valve timing is off and if so how do i go about resetting that? Here are the pics, any information would be greatly appreciated.

Here are the links to the pictures

http://www.freepichosting.info...1.jpg

http://www.freepichosting.info...3.jpg http://www.freepichosting.info...2.jpg


Modified by huntin5L at 3:32 AM 5/7/2007

180fan
Posts: 7799
Joined: Sat Dec 14, 2002 12:16 pm
Car: 89 fastback

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to reset a skipped timing chain properly, you'll need to go through the paces of a timing chain job. There isn't much of a reason why a chain would skip, unless a tensioner were going out or the guides on the side (common) have given out. My suggestion would be to do a chain job (unless it was recently done).

Regardless, I'd still suggest you look over your chain assembly. It looks like something else may have happened down below from the look of a link or two at your chain on the cam sprocket.

huntin5L
Posts: 256
Joined: Sun Dec 22, 2002 8:45 am

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Interesting if that is the case, the chain is loose, i can push it it in by like an inch from the side if i stick my hand in thru the top of the timing cover. Any good links to show me how to reset the valves for the correct timing? Ill try to do some more searching on this forum. If anyone else has anymore info it would be much appreciated. Thanks again, Bob.

huntin5L
Posts: 256
Joined: Sun Dec 22, 2002 8:45 am

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bump, anyone?

huntin5L
Posts: 256
Joined: Sun Dec 22, 2002 8:45 am

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It looks like my chain skipped two teeth.

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Pirate_Freder
Posts: 282
Joined: Sat May 05, 2007 5:24 pm
Car: 1993 240SX Coupe

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like that guy was saying, timing chain job.

even if you don't replace any parts you are going to have to take it all apart and set it to TDC again.

huntin5L
Posts: 256
Joined: Sun Dec 22, 2002 8:45 am

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Well i am going to do the chain job, now since it is off by two teeth i just need to set the motor to tdc, which i have and the cam gear's keyway is facing straight up, which is correct right, and the then also line up the crank gear's keyway and just match up the silver links to the corresponding marks on the teeth of the gears and i should be all set right? I should also then set my distributor so it points to the #1 plug, correct? The only problem i forsee is getting the crank bolt off without moving it once it is set to TDC.
Modified by huntin5L at 3:53 PM 5/9/2007

180fan
Posts: 7799
Joined: Sat Dec 14, 2002 12:16 pm
Car: 89 fastback

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you still can't be sure as to one or two links. there is a tension side and slack side of the chain. The slack side number of links does not equal the number of links on the tension side. You cannot be sure that you've got the right link if you're taking a guess. Additionally, in my previous post I mentioned you might want to take a closer look at what's happening below as one of those links at the very least looked like it wasn't in the best of shape.

huntin5L
Posts: 256
Joined: Sun Dec 22, 2002 8:45 am

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Yeah that is true, i didn't think about it that way. I forgot about the tensioner, because the chain is loose. I have to take a few more things off to be sure, so ill take some pics when i get the timing cover ofF. Thanks, Bob
Modified by huntin5L at 6:42 PM 5/10/2007


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