norfolkluego
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| posted on 11/7/10 at 05:42 PM |
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Oops - big bang
Sprinting at Debden today, had a bit of a problem, just coming up to the finish line on my second pratice run, foot flat down on the throttle pedal
and bang. Came across the line with smoke, steam, oil pouring out everywhere. My helmet and visor were covered in gunk, it was everywhere. Pulled off
to the side and got out sharpish as there was smoke pouring from under the bonnet and there was a nasty looking oil and water mix dripping from
everywhere. Got towed back to the paddock and found a damn great hole in the crankcase.
 
Rescued attachment Crank.jpg
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norfolkluego
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| posted on 11/7/10 at 05:45 PM |
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Obviously done for the day so we trailered it home and started poking about, number 2 carb looks like this, bits of metal everywhere, both sides of
the butterfly (we've now cleaned it up and it actually appears undamaged)
 
Rescued attachment Carb1.jpg
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beaver34
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| posted on 11/7/10 at 05:45 PM |
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ooffff, least you did it properly
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norfolkluego
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| posted on 11/7/10 at 05:46 PM |
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Number 2 plug looks like this
 
Rescued attachment Plug.jpg
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Werner Van Loock
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| posted on 11/7/10 at 05:46 PM |
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ouch, you're also in a game over for this summer position. I destroyed my rear axle 2 weeks ago.
At least it's all repairable.
Haven't seen many zetecs go bang like that, you know the cause already?
replied too fast and didn't see th eother pictures, that looks nasty, possible head damage too. Metal stuff coming throught the valves = not
good
Guess when you drop the sump you'll get to see a disaster
[Edited on 11/7/10 by Werner Van Loock]
http://www.clubstylus.be
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norfolkluego
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| posted on 11/7/10 at 05:47 PM |
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And the sump could do with a clean
 
Rescued attachment Sump.jpg
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iank
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| posted on 11/7/10 at 05:48 PM |
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Something air filter side disintegrated and got into the engine?
Good job zetecs cost pennies.
Did you win?
[Edited on 11/7/10 by iank]
--
Never argue with an idiot. They drag you down to their level, then beat you with experience.
Anonymous
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Werner Van Loock
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| posted on 11/7/10 at 05:54 PM |
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quote:
Originally posted by norfolkluego
And the sump could do with a clean
Is that a chopped sump without capacity compensation? If so then that could be your problem as it wont hold enough oil for demanding applications like
racing
http://www.clubstylus.be
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norfolkluego
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| posted on 11/7/10 at 05:54 PM |
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Simple question really, is there something wrong with it? 
Seriously, when I saw the hole in the crankcase I assumed the bottom end had gone but it seems the piston has let go. If you shine a torch in the hole
in the crankcase(it's that big!!!) and lookg down the spark plug hole you can see the con rod apparently intact, the mangled remains of the pin
and no sign of a piston at all, none.
1. What would cause that kind of failure.
2. Anyone want to buy a Zetec (slightly used - £500 ono )
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Werner Van Loock
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| posted on 11/7/10 at 06:02 PM |
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piston desintegration could be caused by it running lean and having high speed knock going on, as you have injection throttle bodies it could mean 1
of the injectors not delivering the same amount of fuel as the others at high speed. mostly a hole is burned into a piston, but it can also
desintegrate when going well wrong
Does the zetec have oil squirters aimed at the bottom of the piston? If one of those got blocked it could also be the cause icw runnig lean
http://www.clubstylus.be
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norfolkluego
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| posted on 11/7/10 at 06:11 PM |
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quote:
Originally posted by Werner Van Loock
piston desintegration could be caused by it running lean and having high speed knock going on, as you have injection throttle bodies it could mean 1
of the injectors not delivering the same amount of fuel as the others at high speed. mostly a hole is burned into a piston, but it can also
desintegrate when going well wrong
Does the zetec have oil squirters aimed at the bottom of the piston? If one of those got blocked it could also be the cause icw runnig lean
They're actually bike carbs from a Honda Fireblade and I'm pretty sure the fuelling is about right (or rather was about right)
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norfolkluego
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| posted on 11/7/10 at 06:19 PM |
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quote:
Originally posted by iank
Something air filter side disintegrated and got into the engine?
Good job zetecs cost pennies.
Did you win?
[Edited on 11/7/10 by iank]
Don't think it was something air filter related, it had filter socks on and they were full of shards of metal like the carbs so I'm
assuming if they could stop stuff getting out, they could stop it getting in.
Don't think I won no, think I'm in the book as 'retired hurt' (or is that cricket)
[Edited on 11/7/10 by norfolkluego]
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Stuart_B
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| posted on 11/7/10 at 07:01 PM |
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ouch that is very bad.
hope you get it sorted, or maybe a new or seconded hand engine in soon.
stuart
black mk indy, 1.6pinto on cbr600 bike carb's.
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PAUL FISHER
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| posted on 11/7/10 at 07:13 PM |
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Looks like oil control problems to me, lack of oil pressure, has caused the big end to fail, causing the damage to the block, the piston will have
then hit the valves and spark plug etc, pushing/blowing debris back out through the carbs
Could be down in part, to the extra grip you would have been getting on a hot day, on the new R888.
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daviep
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| posted on 11/7/10 at 07:14 PM |
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In my experience running lean tends to burn a hole in the piston.
My bet would be on big end failure allowing the piston to hit the head.
Davie
“A truly great library contains something in it to offend everyone.”
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madteg
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| posted on 11/7/10 at 08:11 PM |
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Feel for you, looks like time for a upgrade. Was it a silvertopor a blacktop.
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norfolkluego
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| posted on 11/7/10 at 08:55 PM |
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Was a Blacktop, more than happy with another one as it's a cracking (no pun intended) engine in that car
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Danozeman
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| posted on 11/7/10 at 09:00 PM |
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The normal failure for a zetec is the con rod bolts letting go hence the need for arp bolts. If as you say the bottom end is ok then you must have
been running very lean and detonated the piston. Oil supply causing the little end to dry out?
Dan
Built the purple peril!! Let the modifications begin!!
http://www.eastangliankitcars.co.uk
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norfolkluego
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| posted on 11/7/10 at 09:36 PM |
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Bottom end looks OK, obviously haven't stripped it down but looking through the new 'viewing window' the bottom end looks OK, the
piston however looks to have been totally destroyed.
Edit.
Just prior to it going pop we'd taken the plugs out to have a quick check on how the engine was running (a rough and ready check I know but
still not a bad indicator) and the plug colour looked spot on. Having said that, the engine did feel very hot, temp gauge was reading around 100.
[Edited on 11/7/10 by norfolkluego]
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mookaloid
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| posted on 11/7/10 at 10:39 PM |
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have you taken the head off yet? this can also be caused by a dropped valve..
"That thing you're thinking - it wont be that."
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norfolkluego
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| posted on 11/7/10 at 11:24 PM |
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quote:
Originally posted by mookaloid
have you taken the head off yet? this can also be caused by a dropped valve..
No, not yet, we intend to strip it down just to try to find out what happened but that can wait for a bit, more interested it getting the car running
again so we can finish the season. I'll post some piccies up when we get it open.
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snapper
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| posted on 12/7/10 at 05:45 AM |
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What pistons (Cast or Forged) ?
What revs when it let go?
I eat to survive
I drink to forget
I breath to pi55 my ex wife off (and now my ex partner)
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norfolkluego
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| posted on 12/7/10 at 09:16 AM |
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Standard pistons so cast.
We had a soft rev limit set on the Megajolt at 7200 and I'm assumung thats what it was doing as I was accelerating as hard as possible towards
the finish line and didn't want to change up.
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Mix
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| posted on 12/7/10 at 03:36 PM |
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Hi
Anyone wondering where the center electrode of that plug has gone - or am I being simplistic?
Regards Mick
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norfolkluego
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| posted on 12/7/10 at 06:27 PM |
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quote:
Originally posted by Mix
Hi
Anyone wondering where the center electrode of that plug has gone - or am I being simplistic?
Regards Mick
I assume it got smashed to pieces by a bit of the piston, it's not just the electrode, the bottom of the plug is totally mashed. Looking at some
of the lumps we've found looks like the cylinder wall got ripped apart too 
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.jpg)
