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Discussion Starter · #1 · (Edited)
I'm going to try to make this as short as possible, but some things require quite a bit description for clarity purposes, so here goes nothing.

I have a 2001 Eclipse GT with 65k miles that I just bought recently. The other owner never did the timing belt component change, so that's what I started with on the car. After doing all that, everything gets put back together, and everything is fine for about a week, and in that week, there was some harder than normal driving. 2 days ago, I started it up, and i immediately heard something wrong with the way the engine was running, so i shut it off. I tried to run it again later, but for a few more seconds than the first time, and this is when it threw a CEL of a P0300. I had already ordered things for a full tune up (cap and rotor, plugs, wires, etc) and figured to start disassembling early. While everything is off, i figured i should double check timing too, so I did. Apparently, my timing belt job wasn't as good as i thought. Timing on bank #2 camshaft was 4 teeth off and there was very little tension between the cams and the water pump, but there was the normal tension around the crank gear and by the tensioner (of course). So I released the tension on the belt by pulling the hydraulic tensioner and loosening the pulley the hydraulic tensioner pushes on while the crank and bank #1 was on their timing marks, and now, my crank is on its timing mark, and the camshaft for bank #2 is on its timing mark, but bank #1 migrated to 8 teeth off time (8 teeth past the timing mark when its spinning clockwise) and with cylinder #1 being at tdc, i have a very bad feeling about that. I know that is confusing as hell, but that's how it somehow happened.

Basically, with this situation in mind, my question is, how likely is it that i did bend valves, and two, how do i get camshaft on bank 1 back on time so i can put the belt on and do a compression test for bent valves? I don't want to spin the camshaft all the way around because that would (at least to my knowledge) definitely make valve to piston contact, but if i try to spin the camshaft backwards (which i know, your not supposed to do either), there is quite a bit of resistance, and i don't know if its just the valve springs resisting or I'm hitting something.

Basically, a shorter way of asking question two is that how do you get a camshaft back on time when it migrated that far off? Any help will be appreciated, even tho i don't know what to expect because idk many people that would have answers to this.
 

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Turning the motor backwards can cause slack in the belt in weird places, and jump teeth in bad places. I think you're ok to turn just that cam backwards to get a mark, provided crank is at zero. It can be very springy turning cams, and when it goes over the top of a lobe it might jump the other way very quickly.

From what I've read 8 teeth off may be a bad thing, but if it wasnt run like that idk.

It's very important to tension the tensioner properly, and even then there are times the belt will be sorta loose in places when you check it.
 

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Discussion Starter · #3 ·
Yeah, my guess is that for the few seconds i ran it, it was at most 3 or 4 teeth off, which is still pretty bad, but idk if its bad enough to bend things. I dont know the timing tolerances of this engine before things start going really wrong. The 8 teeth off happened when the motor wasnt running, all plugs were out and crank was at zero. I hope this didnt cause any damage because as to what i know, 8 teeth off when the motor is running is a sure way to bend stuff.
 

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You would know if one cam was a few teeth off because it would sound awful, like it was missing terribly. With the belt off, turning one cam backwards wont hurt anything unless it is in fact hitting a piston, which you wouldnt be able to damage, just feel resistance. Best bet is to re-do the timing setting everything just right and buying a new tensioner if you didnt already. A compression test will confirm if you have a valve bent or not.
 

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if you back the crank off a few teeth from TDC, it will lower the pistons enough for you to rotate the cams as much as you want. The service manual even explains this procedure in the engine rebuild section.
 
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