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Thread: 01 OB Timing Issue

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    ShiftHappensLTi's Avatar

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    01 OB Timing Issue

    So i have been working on my sister in laws fathers 01 OB 5MT. It threw the timing belt. i got it all timed and he went to start it and it wont run unless you keep it at WOT. thought maybe i was 180 out of time so i took it apart and double checked that 1 was at TDC. then as i triied to line up the marks on the drivers head the cam sprocket simply locks up and wont budge. it will turn but i cant get it anywhere near lined up. he did the tear down and everything and then slit his hand open and had to get 11 stitches so no i get to put it back together but i hit this snag. Is it possible there are bent valves? he didnt take the motor out to do the belt like i told him so i havent torn it down. HELP WOULD BE GREATLY APPRECIATED.

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    Director HolyCrapItsFast's Avatar

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    Quote Originally Posted by ShiftHappensLTi View Post
    So i have been working on my sister in laws fathers 01 OB 5MT. It threw the timing belt. i got it all timed and he went to start it and it wont run unless you keep it at WOT. thought maybe i was 180 out of time so i took it apart and double checked that 1 was at TDC. then as i triied to line up the marks on the drivers head the cam sprocket simply locks up and wont budge. it will turn but i cant get it anywhere near lined up. he did the tear down and everything and then slit his hand open and had to get 11 stitches so no i get to put it back together but i hit this snag. Is it possible there are bent valves? he didnt take the motor out to do the belt like i told him so i havent torn it down. HELP WOULD BE GREATLY APPRECIATED.
    Sorry for the delay...

    First if I am correct is this what we are dealing with?


    Last edited by HolyCrapItsFast; 03-21-2012 at 02:29 PM.

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    ShiftHappensLTi's Avatar

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    Yes u are correct

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    Director HolyCrapItsFast's Avatar

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    Ah ok... The only reason I can think of for the sprocket to bind during rotation is that the crank is off TDC or 180* out and a valve is hitting a piston. It doesn't take much to bend a valve and it is possible that has occurred. There will be some resistance while you rotate the cam because it has to push open valves while you rotate it but it shouldn't bind. you need to align the mark on the crank sprocket with the mark on the block so it is at TDC and then rotate your cams clockwise till the marks on the sprockets line up with the marks on the cover. Then when you install the belt you simply line the marks on the belt with the marks on all the sprockets as outlined above... Also for good measure I found this write-up which is similar to your motor. http://lovehorsepower.com/joomla/ind...d=48&Itemid=64

    Once the motor is together a compression test will reveal whether you have a bent valve or not. Beyond that you may want to check your plugs that they are not fouled and verify the gap.
    Last edited by HolyCrapItsFast; 03-21-2012 at 08:49 PM.

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    ShiftHappensLTi's Avatar

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    Ok then all I can think of this that it has bent valves because i verified TDC on #1. there is the normal resistance up until about an inch and a half before the marks align then it binds. all thats left i guess is to pull the motor and then check it because it was taken apart again to double verify timing and now it wont go into time at all.

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    Director HolyCrapItsFast's Avatar

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    I am very sorry. I can't really think of anything else that would cause that. I think the heads are going to have to come off. Hopefully some one else will have some ideas as well.

    The thing that has me wondering is a bent valve alone should not bind the cam. If any thing a bent valve will simply remain open but it should still travel from that point to it's fully open state with out binding any further. That's why I think something is actually contacting something else. When you do remove the valve cover to investigate, put the cam in a relaxed state on the suspect cylinder with the valves closed and check the spring height. If it is a bent valve you should be able to notice some difference in height between springs.

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    Director HolyCrapItsFast's Avatar

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    Actually I'm remembering something now... when the mark on the block lines up with the mark on the crank sprocket the pistons are not at TDC. You need to verify the crank sprocket marking lines up with the mark on the block. Don't concern yourself with TDC but only the marks on the sprockets. Remeber that TDC is relevant to ignition spark, not valve timing.

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    When you have the marks lined up, all the pistons are actually center stroke.....not TDC like you would do on other vehicles.

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    ShiftHappensLTi's Avatar

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    Is the 252 interference or no? I didn't think it was

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    Quote Originally Posted by ShiftHappensLTi View Post
    Is the 252 interference or no? I didn't think it was
    Everything after 98 is interferience

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