Fantastic!!!!
- Thread starter Burty
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Burty
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Burty
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Burty
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Ice Kiddie
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- Just the one :-(
Oh dear... that's very upsetting 
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Burty
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in a nut shell this is what i believed happened.
piston number 2 gave up and broke up causing it to sieze in bore
crank and rods moving at 7500rpm said tough **** we aint stopping and ripped the rod off the piston
no.2 rod then smashed its way around punching a hole in the front half by the injectors and a hole in the bottom of hole no.1
all the bits of piston, bearings etc went everywhere including into the new hole in bore No.1 ruining that liner and piston too
Dunno why spark plug sheared but look on the bright side i now have some reeds and a cage i can sell to Taz
piston number 2 gave up and broke up causing it to sieze in bore
crank and rods moving at 7500rpm said tough **** we aint stopping and ripped the rod off the piston
no.2 rod then smashed its way around punching a hole in the front half by the injectors and a hole in the bottom of hole no.1
all the bits of piston, bearings etc went everywhere including into the new hole in bore No.1 ruining that liner and piston too
Dunno why spark plug sheared but look on the bright side i now have some reeds and a cage i can sell to Taz
Ice Kiddie
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- Just the one :-(
Mebbe loose piston flew up to hit inside of spark plug, pushing conductive core outwards and cracking/shearing the ceramic?Burty said:
The plug snapped because the piston has hit the head really hard and the resulting shockwave hammered the end of the plug off.
The Pistons in that motor are Mahle's. They stopped making these pistons 10 years ago and as they weren't renowned for pin failure like the wiseco's that replaced them they may well be the original pistons, or new old stock. Either way I reckon they've been in there for quite some time and have probably just been re-ringed over and over. The side pins on those pistons are covered over by the ring and were still well in there, not loose at all. They were the best pistons ever made for the 2.5.
Any way it seems as if old age finally got to them. It looks as if the skirt broke up on No.2 piston. The side of the piston is fine no heat marks but in one area it looks as if some debris has got up the side and jamed it in there. The rod has then ripped out the back and proceeded to hammer the crap out of the engine internally including hammering the piston into the head. The top of the piston has a ring round it that matches up with the head. This maybe how the end of plug broke off. It also put a hole in the front case half and another hole just under the rod slot for cylinder No. 1. A roller from the small end roller bearing on the previoulsy mention No. 2 piston has then got into No. 1 snapped in half and found its way past the piston leaving two scores in the cylinder wall. Its/they have then bounced around inside No. 1 cylinder, hence all the half roller shaped marks in the top of the piston. Half the roller was found imbedded in the top of the piston and the other half in imbedded in the head.
So I guess it needs lots of welding, two sleeves, a new rod, 6 new pistons, bearings and gaskets etc. And best have some new reeds too as one of the cages has had a bit of a knock.
The Pistons in that motor are Mahle's. They stopped making these pistons 10 years ago and as they weren't renowned for pin failure like the wiseco's that replaced them they may well be the original pistons, or new old stock. Either way I reckon they've been in there for quite some time and have probably just been re-ringed over and over. The side pins on those pistons are covered over by the ring and were still well in there, not loose at all. They were the best pistons ever made for the 2.5.
Any way it seems as if old age finally got to them. It looks as if the skirt broke up on No.2 piston. The side of the piston is fine no heat marks but in one area it looks as if some debris has got up the side and jamed it in there. The rod has then ripped out the back and proceeded to hammer the crap out of the engine internally including hammering the piston into the head. The top of the piston has a ring round it that matches up with the head. This maybe how the end of plug broke off. It also put a hole in the front case half and another hole just under the rod slot for cylinder No. 1. A roller from the small end roller bearing on the previoulsy mention No. 2 piston has then got into No. 1 snapped in half and found its way past the piston leaving two scores in the cylinder wall. Its/they have then bounced around inside No. 1 cylinder, hence all the half roller shaped marks in the top of the piston. Half the roller was found imbedded in the top of the piston and the other half in imbedded in the head.
So I guess it needs lots of welding, two sleeves, a new rod, 6 new pistons, bearings and gaskets etc. And best have some new reeds too as one of the cages has had a bit of a knock.
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TheOrs
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Burty said:
Probably still run faster than my boat
And there was me yesterday, feeling sorry for myself 'cause I need a new trim cylinder (£150) after 13 years.
Feeling for you dude.
roofer
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feel for you burty dude
MrRob
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HOLLY MOLLY! Were you using TNT for fuel?
On the bright side and being honest with yourself I am sure you feel some sense of pride due to doing so much damage while attempting such insane speeds! Got any spares off that which would come in handy for my 225 promax?
On the bright side and being honest with yourself I am sure you feel some sense of pride due to doing so much damage while attempting such insane speeds! Got any spares off that which would come in handy for my 225 promax?
Dangerous
Senior member
I did exactly the same at Cardiff bay national putting a hole in the side of the block and i also snapped a plug and a rod. We thought ours was the computer but ya neva know. Ironic that we did the first race at about 7k for an hour, then towed a junior in the second race at about 4500k did about 20mins then she let go.
Taz
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Ah mate burty dude bad luck! and i was only thinking how good your engine was standard compared to the tuned ones, What are you going to do get it rebuilt or scrap it? Maybe intreasted in sum spares
Sod the merc get a yam or sumthing thats what i keep thinking
Sod the merc get a yam or sumthing thats what i keep thinking
Taz
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Oh yeh 5 petal reeds are 440 dollars to your door from Jay Smith
Taz
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Dangerous were bouts you from in essex?
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