325I Head off & on now timing off?

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Avinit4
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Wed Nov 09, 2016 3:58 am

Hello people, well due to allowing someone else to work on my e30, I ended up finding they had sheared 2 exhaust manifold studs, hence why needed to take head off. However when engine started up the knocking/Tapping meant switched straight off again.
Anyway I thought I'd replaced everything exactly same (as on several previous Occasions) until I started her of course.
I'm thinking when Head was in Engineering place to remove broken studs, that somehow while doing it they moved the cam, just a small amount but enough to put everything out. Action taking
Have striped back down to check timing marks on cam and crank, if out then correct it by moving cam to correct place with timing belt removed. Does that sound about right to you chaps? Looking for some reassurance I'm going right way or that I'm well off and need to do something else, I'm not fused which I just want to sort it, hate working in the road when its cold wet and dark bla bla cheers
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reggid
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Wed Nov 09, 2016 8:37 am

if you ran the engine with timing far enough out probably got a bunch of bent valves. this is who ever timed it ups fault not the machine shop. how far out was it?

it could also simly be the valves are not adjusted correctely, you need to redo them after the head is torqued down
E30 325is with M20B31
Speedtouch
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Wed Nov 09, 2016 9:56 am

Yes, check the valve rocker arm clearances first before taking it all apart.

http://www.e30zone.net/e30zonewiki/inde ... M20_engine
///M aurice
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Brianmoooore
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Wed Nov 09, 2016 2:00 pm

After checking/setting clearances, I'd do a compression test.
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Avinit4
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Wed Nov 09, 2016 6:42 pm

No one set.timing, I just replaced in same place... Moved enough to push sparkplug gap closed... Valve stems I think are good thanks.
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Avinit4
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Wed Nov 09, 2016 6:44 pm

Also done valve clearances twice already so there's good
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Avinit4
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Wed Nov 09, 2016 6:44 pm

Also done valve clearances twice already so there's good
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Avinit4
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Wed Nov 09, 2016 6:47 pm

Had new crankshaft and rings 15000 miles ago so pressure still good.
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Brianmoooore
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Wed Nov 09, 2016 6:53 pm

Avinit4 wrote:Had new crankshaft and rings 15000 miles ago so pressure still good.
Won't be if any valves are bent!
Piston cannot come into contact with (correct) spark plugs whatever the timing is set at. The same cannot be said for the valves, which should both be partly open when a piston is at TDC, every other turn of the crankshaft. If the timing is out, either way, and one of the valves is more open than it should be, it WILL be hit by the piston.
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pianist
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Wed Nov 09, 2016 11:07 pm

Am I getting this right? You took the timing belt off and then removed the head without spining any of the pulleys on the engine or head? Then when you got your head back from the shop you just bolted it back on, and slid the timing belt back on the pulley assuming that the pulley on the head rests in the same spot as when you have removed it? Without checking the timing marks?
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Avinit4
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Fri Nov 11, 2016 2:06 am

No that's not what I done... My reference to timing belt removed is saying that's what I intend to do if Cam mark is out, to get back in correct place. When I took Head off I cabled tied the timing belt to the cam timing belt pulls, and marked where was on the Head. No1 piston was TDC at start.
So valves defo hit pistons then pianist, but only just. I say that because sounded more like loud tapping noise than a loud nocking noise. i guess only way to know for sure is to get myself a compression tester yes?
When weathers better If see where timing marks actually are now! Thanks for your input people.Hope I've made more sense now regarding what I've done? Cheers
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Fri Nov 11, 2016 10:35 am

Yes, unless the tapping is simply down to the oil having drained from the head/top end of the engine while it was removed?
///M aurice
ECU Upgrade EPROM Chips, £40 posted within the UK. Note these are not Zone chips.
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