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Model specific boards => Golf mk2 => Topic started by: twistedblack69 on 21 January 2009, 20:18

Title: And it begins...cambelt went on the motorway :(
Post by: twistedblack69 on 21 January 2009, 20:18
Luckily managed to get onto the hard shoulder from doing 70 in the fast lane. Turns out something has dug into my cambelt while it was going around, and perforated it in 2. This in turn has bent valves, so gotta get it sent off and head skimmed  :sick: gonna be out 'til the weekend earliest. Joyous
Title: Re: And it begins...cambelt went on the motorway :(
Post by: dan7 on 21 January 2009, 20:20
Bad luck mate. And good luck with the fix.
Title: Re: And it begins...cambelt went on the motorway :(
Post by: Jay on 21 January 2009, 21:20
Bad luck matey, maybe time for an engine upgrade ?  :rolleyes:
Title: Re: And it begins...cambelt went on the motorway :(
Post by: DAVEMARX on 21 January 2009, 21:28
are you serious?......
Title: Re: And it begins...cambelt went on the motorway :(
Post by: twistedblack69 on 21 January 2009, 21:48
Yea, a couple years in the future, when I have some no claims, a VR6 swap maybe called for.

Dave: yea I'm being serious. There was no wear on it, 'cause obviously you had it changed end of 2007, f**k knows what happened.
Title: Re: And it begins...cambelt went on the motorway :(
Post by: DAVEMARX on 21 January 2009, 22:08
yeah the cam was sweet.....f**k man thats mental sorry dude i think its just plain old bad luck i feel for ya m8....chin up ay... :smiley:
Title: Re: And it begins...cambelt went on the motorway :(
Post by: Ben Lessani on 21 January 2009, 22:32
I thought the 8v was non interference??
Title: Re: And it begins...cambelt went on the motorway :(
Post by: twistedblack69 on 21 January 2009, 22:40
What does this mean??
Title: Re: And it begins...cambelt went on the motorway :(
Post by: Ben Lessani on 21 January 2009, 22:45
That even if the cambelt snaps, the pistons don't make contact with the valves. Which means, set timing up, pop a new belt on and away you go.

I didn't think you had to skim the head either, even if you bent valves?
Title: Re: And it begins...cambelt went on the motorway :(
Post by: Chris-White on 21 January 2009, 23:44
I thought the 8v was non interference??

I also thought this.
Title: Re: And it begins...cambelt went on the motorway :(
Post by: twistedblack69 on 22 January 2009, 00:00
I've just read up on it, and apparently the only interference engines in the mk2's were the 16v engines. Wtf!! How did this happen??
Title: Re: And it begins...cambelt went on the motorway :(
Post by: Ben Lessani on 22 January 2009, 00:00
Unless he's running a lairy cam - I've heard that could affect it, not the duration, but the lift.

How do you know your valves are bent - I take it you can't turn it over by hand?
Title: Re: And it begins...cambelt went on the motorway :(
Post by: twistedblack69 on 22 January 2009, 00:02
My dad's a mechanic, he was taking it apart earlier, I don't have the foggiest. Apparently the belt actually jumped the pulley or something.
Title: Re: And it begins...cambelt went on the motorway :(
Post by: Ben Lessani on 22 January 2009, 00:06
That's some amazingly bad fortune if it has bent a valve.

But take this opportunity to replace the valve stem seals and overhaul the tappets - saves doing it twice.

Or even stick in a 268 cam, a quick port and polish and a 2.0 lump :evil:
Title: Re: And it begins...cambelt went on the motorway :(
Post by: danny_p on 22 January 2009, 00:24
i've droped a belt on an 8 valve before  and nothing bent  it just  coughed and farted to a hault,     if 16v or 20v drops belt  ouch 
Title: Re: And it begins...cambelt went on the motorway :(
Post by: twistedblack69 on 22 January 2009, 00:56
He said the belt jumped the cam or something...I'm not sure, I'm trying to slowly learn haha but I am known throughout my circle of close friends as the one that has the luck with cars........that's sarcasm btw  :embarassed: :embarassed: lol
Title: Re: And it begins...cambelt went on the motorway :(
Post by: pro-biotic on 22 January 2009, 01:04
i've droped a belt on an 8 valve before  and nothing bent  it just  coughed and farted to a hault,     if 16v or 20v drops belt  ouch 

x 2

tell your old man to stop, put a belt on and try the engine.

your old man means its jumped the cam sprocket.... it will be futile to strip it down TBH

Title: Re: And it begins...cambelt went on the motorway :(
Post by: billinjah on 22 January 2009, 02:09
all 4 cylinder vw engines are interference i thought? pg's certainly are.
Title: Re: And it begins...cambelt went on the motorway :(
Post by: Ben Lessani on 22 January 2009, 08:42
I'm trying to slowly learn...

Look here http://auto.howstuffworks.com/engine1.htm, in the diagram, P (crank) and I (cam) rotate in harmony - this is ensured from your timing belt. If the belt snaps, it means that the piston (N) is at risk of hitting the valve (A).

In that animation, the engine could be interference - unless the piston crown was recessed, it would impact the valve.
Title: Re: And it begins...cambelt went on the motorway :(
Post by: twistedblack69 on 22 January 2009, 09:07

x 2

tell your old man to stop, put a belt on and try the engine.

your old man means its jumped the cam sprocket.... it will be futile to strip it down TBH



Yup tried it
Title: Re: And it begins...cambelt went on the motorway :(
Post by: Martz on 22 January 2009, 09:17
i've droped a belt on an 8 valve before  and nothing bent  it just  coughed and farted to a hault,     if 16v or 20v drops belt  ouch 

I had this on my old 20v, 80mph on the A40 accelarating and pop, made a right old mess. all 20 valves were shot engine was proper fooked!


Good luck with the fix mate, lucky your old mans a mechanic!
Title: Re: And it begins...cambelt went on the motorway :(
Post by: DAVEMARX on 22 January 2009, 11:24
i wonder if its got anything to do with forceing the power steering belt back on if it was to tight it could of buckled the pulley on the crack causeing it to wobble thus leading it to jump a few teeth and snapping under presure...

the head and gasket were changed at the same time as the belt went on so i dont think theres any need to reskim the head unless the gaskets fooced..

you were unlucky but you might be a bit lucky at the same time in that its only a case of replacing the belt and valves so its a good job theres only 8.....which is the best thing about the 8v same great look just without the bigger bills and less to go wrong.

good luck m8 let us know how it goes....

dave

 
Title: Re: And it begins...cambelt went on the motorway :(
Post by: rubjonny on 22 January 2009, 12:59
i doubt it, for a start the timing belt runs off a sprocket inside the belt pulleys, would take serious force to bend that and your engione would be totally trashed if you had :grin:
Title: Re: And it begins...cambelt went on the motorway :(
Post by: danny_p on 22 January 2009, 18:41
if there has been piston valve contact,   you will have to be carefull with what you reuse and check everything as the valves are square onto the piston,  possoblity of buggering, the valves, valve guides, tappets and cam.

8V  pistons have quite a dish in them tho  and the valves are in the chamber roof so shoudl be ok
Title: Re: And it begins...cambelt went on the motorway :(
Post by: twistedblack69 on 22 January 2009, 18:52
3 exhaust valves and an inlet valve shot. Got the head and manifold off, getting the head skimmed tomorrow and hopefully she should be back on the road saturday sometime
Title: Re: And it begins...cambelt went on the motorway :(
Post by: DarnPB on 22 January 2009, 19:51
If you are looking at skimming the head, I would get it dimensioned first. If these are non interference engines, then something somewhere has gone wrong, possibly due to the following.

1. The head may have been skimmed before, possibly due to overheating or purely for tuning. Anyhow, material would have been lost bringing the valves closer to the pistons and thus losing the non interference properties.

2. You may have a high lift cam in there, again for increased performance. This may also cause the engine to lose its non interference properties.

3. A combination of the above.

Now if the head has been skimmed and you go and skim it again, you could take it out of limits.
Title: Re: And it begins...cambelt went on the motorway :(
Post by: Mr Blue on 22 January 2009, 20:07
Are you running a cambelt cover?

If not then maybe a stone or something has flicked up between the belt and nocked it out.