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fun times with timing belts and cam shafts

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robbo
Posts: 115
Joined: Tue Jul 03, 2012 3:39 pm
Location: Sydney

fun times with timing belts and cam shafts

Post by robbo »

assuming most people would have gotten bored of the frantic posts on facebook asking for help when i had problems changing the timing belt yesterday/today.
began with a basic gearbox and engine oil change, both went fine. then went to change the timing belt over and replace the cam shaft oil seal and the other gasket behind the timing belt plate. this was due to the crap built up on the tensioner that i was not happy with.
Image

lined up the timing perfectly and had the spark plugs out to confirm that tdc indicated was tdc for piston 1, all good.

pulled off the cam shaft oil seal and then the plate, cleaned it up and put it back together with a new seal and gasket goo for the plate.
go to put the new belt on, discovered that i put the timing out a few teeth and some helping advice from Adam (dexi) put me on the right track to sorting out that problem. belt off, line up the timing, get the timing right. belt back on and tensioned correctly, double check spark plug holes to make sure valves not off. go to rotate the crank by hand and it moves smoothly a split second then jumps teeth on the belt so i go and check to the cam shaft pulley to find that it hasn't moved an inch. won't budge at all... shit
repeated this process plenty more times during the day and stripping back all of the work from the night before to see what i'd done wrong but still can't get the cam to budge in either direction. at the moment rego is due in 4 days and the car has been rolled out of the gf's rents garage onto the street, where it will be towed either back to mine or to a workshop depending on what the problem is likely to be. Seriously considering taking it off the road for an extended period to build it up to a better machine than it currently is. any advice on where to start with this problem, or if anyone has experienced a problem like this before? it's a stage 2 cam and i think it may also have stronger valve springs from memory, not sure if that helps?
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zoomzoom
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Post by zoomzoom »

turn the crank back to 17c btbc, if I read it right you're got the pully mark on 0,if so the pistons are hitting the valves



zoomzoom
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baz
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Location: Hobart / Tasmania

Post by baz »

So go back to the beginning, pull the timing belt off!..Set the crank to TDC #1. Spin the cam around so that necessary markings line up (crank is in the right position & the cam is in the right position) Will need to spin the crank a bit at a time & then the cam a little at a time to work your way back around ..Wack the belt back on & it should be fine..If its not then it sounds like the cam is jammed from when you put it in or the cam is incorrectly timed up & it's possibly hitting a valve..For more info, Post a picture of the engine at TDC & the position of the cam
My old exa I created from granny spec to a neat little BRIGHT car: http://forum.n12turbo.com/viewtopic.php?t=3903

Current Car: 2004 Vz SS Ute
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tassuperkart
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Post by tassuperkart »

I know what he did.
He removed the cam cover backplate to change the seal, removed the gasket and didnt use a gasket when reassembling it all.
Camshaft endfloat is set by this gasket and without a gasket there, the ally cover has locked up the cam.

Oracle
Forcd4 wrote:Oh fuk no dude it's you a again, the oracle.
robbo
Posts: 115
Joined: Tue Jul 03, 2012 3:39 pm
Location: Sydney

Post by robbo »

thanks guys, i got a mobile mechanic specialising in timing belts to come look at it yesterday. told him step by step everything i did and he went over the engine, agreed with Evan that i would need to create a new gasket to put in place. the other problem related to this was that i have caused the valves to need readjusting hence the cam being locked up so for $250 he will readjust the valves and fit the timing belt, whilst letting me look on and learn how/where i f****d up so i figure that's a price worth paying
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baz
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Location: Hobart / Tasmania

Post by baz »

tassuperkart wrote:I know what he did.
He removed the cam cover backplate to change the seal, removed the gasket and didnt use a gasket when reassembling it all.
Camshaft endfloat is set by this gasket and without a gasket there, the ally cover has locked up the cam.

Oracle
Similar problem happened to a friends 4age, over tightened the cam caps, locked them up real proper lol
My old exa I created from granny spec to a neat little BRIGHT car: http://forum.n12turbo.com/viewtopic.php?t=3903

Current Car: 2004 Vz SS Ute
mret
Posts: 5
Joined: Mon Feb 18, 2013 8:05 pm

Hey

Post by mret »

Hey mate did u end up sorti g it out ?
robbo
Posts: 115
Joined: Tue Jul 03, 2012 3:39 pm
Location: Sydney

Post by robbo »

Guys coming out to repair it on the 13th march then I'll re rego it
mret
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Joined: Mon Feb 18, 2013 8:05 pm

.

Post by mret »

No worries if u get stuck I can help if u live near me
robbo
Posts: 115
Joined: Tue Jul 03, 2012 3:39 pm
Location: Sydney

Post by robbo »

Thanks mate, appreciate it :)
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