piston seized [Archive] - ATV Riders Forum

400exstunta

10-25-2002, 04:50 PM

grrr
http://www.atvnc.com/pics/piston.jpg
http://www.atvnc.com/pics/piston2.jpg
http://www.atvnc.com/pics/piston3.jpg
http://www.atvnc.com/pics/valves.jpg
http://www.atvnc.com/pics/valves2.jpg
http://www.atvnc.com/pics/valves3.jpg
yeah i seized the piston in the ole 400... guess im goin for the 416

Taco

10-25-2002, 04:51 PM

what in the world did you do?:eek:

Pappy

10-25-2002, 04:52 PM

dam., thats nasty lookin......wtf happened?

Taco

10-25-2002, 04:59 PM

I hope you plan on splitting the cases.:eek:

DEAL

10-25-2002, 04:59 PM

ahhhhhhh :eek:

400exstunta

10-25-2002, 05:04 PM

i was riding in 5th pinned for like 45 seconds and bam.. locked up dont really know what happened.. i was on hardtop in a straight line.. i guess id have to split the case just to clean out the bottom end eh?

Pappy

10-25-2002, 05:11 PM

i would go ahead and do bearings etc in the bottom end...and ...how bad was the cylinder and head damaged...pic is a lil ruff

400exstunta

10-25-2002, 05:14 PM

pretty bad actually.. gonna go with a 416 bore and a je 11:1 piston and a hotcams stage 2, titanium springs, hardened rockers.

Pappy

10-25-2002, 05:17 PM

soinds like a good combo. have the head checked out real good....looks like it took quite a blow also. new vaves etc...you be ok.

get the bottom end checked....maybe need new rod...depends if metal hurt crank etc. ive seen too many people just redo top end....then blow it again because of trash on the cases....

Dave400ex

10-25-2002, 05:25 PM

Yeah check out the Bottom End and all the Clutch Stuff.

Bean

10-25-2002, 06:14 PM

looks like my R piston after 40hrs of work, LMAO

GoLikeHell

10-25-2002, 06:26 PM

Was that a stock bore high comp piston? It looks like you didnt have enough piston to wall clearance, but the spray of piston on the valves shows some preignition.

Sorry to see this happen to you, but could you please give us some more details so we dont duplicate this problem.

Mark

400exstunta

10-25-2002, 06:44 PM

stock everything in the engine. only thing ive got done to it was the free mods... (no choke, grinded welds, jetted, kn filter and precharger....) i go through alot of water on a regular basis. im not talking like a mud puddle, i mean stuff that 4x4s shouldnt attempt... i ruined my rings last week in a lake, went out on a short ride today... had it WOT in 5th and bam it was done. what else ya wanna know?

Taco

10-25-2002, 07:40 PM

No hammers or chisels were involved?

MOUSE

10-25-2002, 07:45 PM

dern that looks almost as bad as my old 97 kx250. i was racing a cr250 back to the trucks from about a mile away. destroyed the thrust washers crank, rod looked like a "s" , split the cylinder all the way up.

on the good side i still beat him to the trucks :macho

400exstunta

10-25-2002, 07:49 PM

mouse where you located in NC at?

YZROOSTINYA

10-25-2002, 07:51 PM

Oh My F-ING GOD, YOU SMOKE CRACK DONT YA BOY!

WOT IN FFTH FOR 45ECS!!!!!!!!

must be bad muffler bearings!

400exstunta

10-25-2002, 07:55 PM

haha yeah i spose soo. but i mean stock engine and plenty o oil. that shouldnt kill the piston like that....

MOUSE

10-25-2002, 08:02 PM

Originally posted by YZROOSTINYA
Oh My F-ING GOD, YOU SMOKE CRACK DONT YA BOY!

WOT IN FFTH FOR 45ECS!!!!!!!!

must be bad muffler bearings!

man i almost fell out the chair with that one :devil

Guy400

10-25-2002, 08:23 PM

Originally posted by Taco
No hammers or chisels were involved? I agree, that piston looks like it was hit with a hammer until it broke. Notice how the face of the piston has been utterly destroyed, all dented and crumbled, yet the head only has some damage on the one side of the chamber. Looks like some frustration was taken out on this piston before the pic was taken.

ridesa02400EX

10-25-2002, 08:38 PM

if u had bad rings u shouldnt have riden at all the oil will go right past the rings and be burnt iin no time

ridesa02400EX

10-25-2002, 08:41 PM

I did the exact same thing except i went with a 440 kit and i get it back tomorrow:D woo hoo!

redrider ex

10-25-2002, 08:48 PM

10-25-2002, 08:50 PM

Originally posted by 400exstunta
grrr
http://www.atvnc.com/pics/piston.jpg
http://www.atvnc.com/pics/piston2.jpg
http://www.atvnc.com/pics/piston3.jpg
http://www.atvnc.com/pics/valves.jpg
http://www.atvnc.com/pics/valves2.jpg
http://www.atvnc.com/pics/valves3.jpg
yeah i seized the piston in the ole 400... guess im goin for the 416

Holy cow.... :huh ...

400exstunta

10-25-2002, 09:03 PM

ok yes there was oil in it. and no i didnt beat it with a hammer. or anything else for htat matter. the "white spots" on the head are actually aluminum that melted to the valves from the piston... the head isnt that bad, at least as bad as it coulda have been.