TangoMan
|
| posted on 25/6/07 at 07:30 PM |
|
|
Could this be the cause of my misfire??
I reckon I might have found out why I got a misfire on the way to Le Mans.
I thought the tappets were a bit noisy!! 
I guess it didn't like running over 7K for a fair time along the payage.
I have seen a few broken pistons in my time but never come across one that was completely gone. The bad news is the head has taken some abuse as well
and may be scrap. The good news is the cams are OK.
I just need to work out what caused it now. I guess either the big end bolts let go (but I am not sure as the rod is still attached to the crank
journal) or the rod stretched to the point of the piston hitting the head or the piston just broke up from the abuse. I reckon I will go for stronger
ARP bolts in the new engine.
Summer's here!!!!
|
|
|
|
|
TGR-ECOSSE
|
| posted on 25/6/07 at 07:35 PM |
|
|
Just a guess but that would probably cause a missfire  Have had a piston snap in 2 before but dont think i've seen 1 that bad  Enjoy the
rebuild
Ronnie
|
|
|
big_wasa
|
| posted on 25/6/07 at 07:44 PM |
|
|
Rebuild ?........................Its scrap 
Still £250 will sort that...cheaper than a bike engine 
|
|
|
Peteff
|
| posted on 25/6/07 at 07:51 PM |
|
|
I've had an exhaust valve melt
and shotblast the piston to death but not as drastic as that.
yours, Pete
I went into the RSPCA office the other day. It was so small you could hardly swing a cat in there.
|
|
|
jambojeef
|
| posted on 25/6/07 at 08:12 PM |
|
|
Wow!
Excellent work!!
I dont suppose you want a 1.8 Zetec block and head do you?
Free to a good home but no idea whether its sweet or sour?!
Geoff
|
|
|
Jon Ison
|
| posted on 25/6/07 at 08:18 PM |
|
|
That should have run............
|
|
|
myeates
|
| posted on 25/6/07 at 08:21 PM |
|
|
brothers ford ka had piston gone at 50000 miles it stopped on him and when engine was stripped the piston was missin and it was the same one !! just
completely gone not even markings on the other chambers from bits of metal in oil.
|
|
|
TangoMan
|
| posted on 25/6/07 at 08:22 PM |
|
|
I did run.
I drove it into the workshop when the breakdown truck brought it back.
I have another 2.0 engine lined up for sensible money. Well OK £175 which is a bit steep but it comes with a guarantee.
Just need to swap all the bits over and strip the head to have a better look.
Summer's here!!!!
|
|
|
Catpuss
|
| posted on 25/6/07 at 08:25 PM |
|
|
Was the piston teleported out?
|
|
|
GeoffB
|
| posted on 25/6/07 at 09:10 PM |
|
|
quote:
TextStill £250 will sort that...cheaper than a bike engine
7000rpm...tickover
|
|
|
TGR-ECOSSE
|
| posted on 25/6/07 at 09:19 PM |
|
|
quote:
Originally posted by big_wasa
Rebuild ?........................Its scrap
Still £250 will sort that...cheaper than a bike engine
Thats not scrap remember its a real engine
[Edited on 25/6/07 by TGR-ECOSSE]
|
|
|
TangoMan
|
| posted on 25/6/07 at 09:55 PM |
|
|
I is a bit past a rebuild as the bore is scored about 2mm deep.
But at least it stayed together which saved me loads of grief. French law doesn't allow my breakdown service to work from French motorways so I
needed to drive off the payage and onto an N road.
A bike engine would have been spread all over the road whereas I could still drive, albeit very slowly, through the paystation and onto an N road.
And it wouldn't be easy to replace a BEC for under £200.
Summer's here!!!!
|
|
|
rusty
|
| posted on 25/6/07 at 10:00 PM |
|
|
Sorry but that is good, I like it, put a hole now meaning to running on three.
|
|
|
davie h
|
| posted on 26/6/07 at 12:37 AM |
|
|
i had a guy come into the place i used to work with a misfire and heavy rattle on a vectra gsi v6 i ended up taking the head off the faulty bank and
found a piston had turned to dust and i mean dust no large chunks just a metal powder covering the sump and no score marks except from where the
gudgeon pinon had hit the bore had me and the other mechanis scratching our heads
|
|
|
jollygreengiant
|
| posted on 26/6/07 at 04:41 AM |
|
|
quote:
Originally posted by TGR-ECOSSE
quote:
Originally posted by big_wasa
Rebuild ?........................Its scrap
Still £250 will sort that...cheaper than a bike engine
Thats not scrap remember its a real engine
[Edited on 25/6/07 by TGR-ECOSSE]
Sorry but it is SCRAP. Just think about all the metal particulates from THAT piston. They will have got into the oil ways. The problem is that you
will NEVER get all the particulates out. ANY rebuild of that unit WILL result in an un-reliable unit that you would never feel happy with.
Take the rest of the bits off the engine and turn it into a garden ornament with soil in the bores and plant in it.
Spend the rest of your hard earned pennies on a reliable engine that you have seen running and do the swop. You know it makes sense. Go down the car
auctions and buy a dog bodied 2.0 mondeo that is a runner (probable cost £250). Pull out the engine and sell the rest for spares that way you will get
some money back.
Beware of the Goldfish in the tulip mines. The ONLY defence against them is smoking peanut butter sandwiches.
|
|
|
TGR-ECOSSE
|
| posted on 26/6/07 at 08:40 AM |
|
|
Thats not scrap remember its a real engine = Sarcasm
|
|
|
awinter
|
| posted on 26/6/07 at 09:11 AM |
|
|
Simalar happened to me, but I new there was more than a misfire, throttle stuck open on a pug Mi16 engine with twin dellorto 45s. Turns out the little
end on piston no2 let go, the piston got mashed to bit taking the valves with it. The conrod still on the crank took the front and rear of the block
out. Found bits of piston on the recovery truck when I got home. Bits of engine all over the engine bay.
|
|
|
CaptainJosh
|
| posted on 26/6/07 at 09:46 AM |
|
|
7000rpm?
For your next engine build I suggest some forged steel pistons, although its a modern engine, cast pistons are not really made for anything 7000+ for
an extended period of time.
What cams do you have? I know its a popular thing to cam up an engine and get alot more power from it, but before you do so you should probably think
about the other engine internals that will get stressed from the extra rpm. Although most engines are understressed for reliability, so uprating your
cams a little bit really won't hurt.
Im amazed this is the first piston failure I have seen on here
But seriousely, get some forged pistons next time and all should be well 
|
|
|
daviep
|
| posted on 26/6/07 at 09:53 AM |
|
|
This was a still running ZZR 1100 engine which had a bit of a miss. When removed had run number 3 big end allowwing the piston to hit the cylinder
head until it disintegrated!
 
Description
 
Description
However it also got home without dropping it guts everywhere
|
|
|
Mark Allanson
|
| posted on 26/6/07 at 07:00 PM |
|
|
1500cc zetec, thats a rare engine
If you can keep you head, whilst all others around you are losing theirs, you are not fully aware of the situation
|
|
|
TangoMan
|
| posted on 27/6/07 at 07:15 PM |
|
|
quote:
Originally posted by CaptainJosh
7000rpm?
For your next engine build I suggest some forged steel pistons, although its a modern engine, cast pistons are not really made for anything 7000+ for
an extended period of time.
What cams do you have? I know its a popular thing to cam up an engine and get alot more power from it, but before you do so you should probably think
about the other engine internals that will get stressed from the extra rpm. Although most engines are understressed for reliability, so uprating your
cams a little bit really won't hurt.
Im amazed this is the first piston failure I have seen on here
But seriousely, get some forged pistons next time and all should be well
ERM...... A Zetec does 7000rpm as standard. OK... maybe not in fifth though
Summer's here!!!!
|
|
|
.JPG)
