Broken Valves .......och

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4wheelin

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Sep 4, 2007
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Location
Peoria Heights, Il.
hey guys check this out, my new White bros carb helped me do all this. I installed this new carb and was tryin to tune it in and next thing i know it makes a branging sound and stops. tore into it to find both vaules brocken off and this piston is trash. My 1st question is why ...how had oil in ........it didn't seem to be running to rich or more importantly to lean. the vaulves was a little noise from the get go. it also smoked so i knew i was gona need rings soon but dam. oil pump maybe stop working and it was just when i was trying to dail in carb? any help would be great. looking for a head, now and this one was built up with a nice cam and hd spring and the works. here is some pictures.any help will be great.
http://i253.photobucket.com/albums/hh70/4Wheelin62/DSCF1127.jpg

http://i253.photobucket.com/albums/hh70/4Wheelin62/DSCF1126.jpg

http://i253.photobucket.com/albums/hh70/4Wheelin62/DSCF1125.jpg
 
To me it looks like the engine jumped time.. like timing chain loose.. cam timing locating pin. Valves could have floated but man you would really have to be reving it hard.. very hard.
Pull the cam out and look at the surfaces to see if you see galling.
 
timing chain seemed fine when i tore it down. was tight . I will pull the cam out and se what it looks like.......i assume iam looking for scoring marks on it. this really suckz.
 
Think of it this way, bore it out 2mm (366 kit), put a .430 cam and a high comp piston, and its even better than new.
 
Looks pretty ugly, I hate to say it but you better check your crank and rod, how long after you put carb. on did it come apart? looks like some foreign object got in there and hammered everything apart, I could see one valve break and it lock up and stop,
 
ok i have a good dude on here gona sell me a head................thanks (whiteBros87)..............iam gona call this a tuff leson learned and I have to wonder if it didn't jumped time some how to cause all this...............anyways now i have a new question ........how do i fish out the broken parts out of the motor. iam sure some got past the piston.......... it broke a hole in the top of it as well. thanks for all the input on this guys, it has been helpfull and i look forward to being able to help someone out myself someday.
 
I would split the cases if you have a hole in the piston and also get a new rod bearing. That would be the best way to go about it.
 
^^^if you havent done that before its really not that hard. Im 16 and did it the fall and i didnt have any problems, but im pretty good with fourwheeler engines idk about you. The only problem i had were the shitty bolts, some still break even if you torque them down to the right specks?
 
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