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View Full Version : Please Help! Leaving For AirForce Soon!


vboy720
09-04-2007, 09:58 PM
Yes I trully am leaving for Lackland Airforce Base soon for Bootcamp. But before I go, I must sell my car. So I am sincerly asking help for those who know a little bit about engines, or installing the timing chain. I have a 1990 Sr20Det Redtop.

<b>The Understanding:</b> In order to install the timing chain the engine must be set at TDC, or Top Dead Center, Which also means the 1st piston is at the very top of its stroke. There are Three marking which should help me line up the Timing Chain Correctly. The marking on the left cam gear should be pointing left/up (11 o'clock ish), and the right cam gear should be pointing right/up (1 o'clock ish). The third mark found on the crank pulley/gear should be pointing down. If done right, the different colored links on the timing chain should line up parallel on top of the markings.

<b>My Question:</b> When I crank the engine to the second mark on the very left on the pulley/gear. That should set it at TDC or the 1st piston at the top. But when I go to turn the left cam gear, and then the right cam gear to the correct position, doesn't that also move the piston, thus moving everything from TDC?

Sorry if my question seems very stupid, but I dont know what exactly is moving the pistons. Whether its only the cam gears, the crank pulley, or both. Hopefully I'll Learn more in the Air Force. Any help or understanding would be greatly appreciated. I hope to serve in the military for everyone, so you may enjoy your freedom :).

P.S. Any people who served Prior in the AF/Military, are welcomed to tell me about your experience.

fliprayzin240sx
09-04-2007, 10:13 PM
Wait your moving the engine to TDC and the chains already off?!?! Your supposed to put it in TDC before anything else. WHen you turn the crank, the cams will turn with it due to the chain. If you fuck it up, you can kiss your valves good bye. Your best bet is take the cams off so the valves wont hit the pistons. Make sure the piston is on TDC, take the oil pump off, you should see a marking on the crank itself. Mate the timing chain marking to that mark (PER FSM). reinstall the oil pump cover, Install the cams (Intake divot should be positioned roughly at 10 oclock and exhaust should be roughly at 2 oclock position). The timing chain should have markings on them, line up the chain to the marks on the the cam gears.

PS: since your changing the chain, dont forget to change the chain guides, most of the time, thats what causes chains to rattle and go bad.

vboy720
09-04-2007, 10:19 PM
I have yet to crank anything with the timing chain off, because i was afraid it would be fucked up. I Have the engine at what i believe is TDC. My timing chain jumped a couple of teeth. So I set the engine at tdc by looking at the marking on the cam gears. and using a stick inside the first spark plug whole and watching it rise.

HalveBlue
09-04-2007, 11:10 PM
Dude...

Check the FSM or search here on Zilvia.

I know for a fact that there's at least one thread on Zilvia that outlines, step-by-step, how to replace a headgasket and, in turn, how to reset timing to factory settings.

Good Luck (with both your car and the Air Force)!

cdlong
09-05-2007, 07:17 AM
all i can say is good luck at boot camp. if you happen to get Osan as your first assignment and work in CE, i'm sure i'll see you.

Grendel
09-05-2007, 07:54 AM
No idea about your timing chain problem, but here are a couple tips for basic :P

Keep a low profile, there were kids in my flight that at the end of 6th week the TI still had no idea who they were. Be that kid.

Wear some normal civillian clothes, dont come in with ridiculous hair. I went in wearing blue jeans, a white t-shirt and I had bleached hair... got called trainee Slim Shady for 6 weeks lol ><

Try to get an out of the way job during cleanup. I had pad crew, sweeping where you form up in the mornings. It was awesome, it was like 15 mins of alone time each day :P

Well thats all I can think of at the moment, hope it helps ya. GL :)

BTW, what job did you get?

cbcustoms
09-05-2007, 08:21 AM
Being prior military. Bootcamp is not that bad so dont stress out about it. Just take the experience for what it's worth. Stay under the radar and do what your told. You'll do just fine. What job are you going to be doing? I was a crew chief on C-141's and C-17's
Good Luck

vboy720
09-05-2007, 02:29 PM
haha glad to see everyone in the military coming to chat! lol ill be going in as security forces. I know a lot of people think its stupid, but im really interested in gettin hands on experience so when i get out, i can be a sheriff. But back to the question...

Ok so i did some research, and found some very useful threads, but none state wether or not i may turn each cam gear individually, and the crank gear at different times. I also ran into another problem putting the timing chain tensioner back on. Should it be pretty hard? should i really have to force it back in the whole? or is there a way to reset the thing all the way back in?

vboy720
09-05-2007, 06:35 PM
sigh, im bouta set this thing on fire.... hopefully insurance will pay for it. lol can someone at least give me a good reference for a mobile mechanic in the sacramento area? I know there are plenty of people from sacramento on here.

cdlong
09-05-2007, 07:37 PM
you could set the crank to 90 deg BTDC and turn the cams all you want. that way, all pistons would be halfway down and you'd have all the clearance you need. once the cams are set, you can turn the crank back to TDC and put the timing chain on. (obviously if you do it with the chain on the whole time, it'll shift the cams once you put the crank at TDC and definitely bend some valves)

sorry, i don't have any tips for you for basic, i never went.

lazierhobo
09-06-2007, 11:16 AM
to get the tensioner back in you compress it all the way then flip the little metal latch on the side up and it locks it in, then you can bolt it in, and knock that little latch off with a screw driver from the top, or as you tighten it in, it might pop off on its own.

when rotating the crank seperate from the cams you have to be really careful. but it sounds like you dont need to rotate much in either direction, so you really should be good. just set the crank at TDC with the screwdriver down plug 1, as you described. then take off the chain, and turn the cams so that the lobes on cylinder one are pointed outwards. intake lobes point all the way left, exhaust points all the way right, then place the timing chain back on, install the tensioner and you should be good to go. crank it over a few times by hand just to make sure everything is good.