new engine seized, what went wrong (pics included)

[cr480r]

now i am getting to the jug boring. my box says .020 clearnace. i called wiseco and they said that it needs to be .030? so what is the right number.

i think wiseco's are all forged so go with the .030" my wiseco is pretty loose in my tecate but it runs really strong. you can hear it slap at low r's

I think you guys mean .002"-.003" not .030"... I would run .003 minimum on a wiseco.. I have never had any problems with wisecos at .0035-.004"....

[2quicktecate]

you know what i meant. 30 thousandth's or .0030

[cr480r]

three thousandths is not the same as thirty thousandths...

[2quicktecate]

so we were right in the first place. you want 30 thousandths. three thousandths like your saying is way tight.

[2quicktecate]

i don't know i'm confusing myself. but thirty thousandths is what we run forged pistons in our race vw engines and more when were on the bottle...

[cr480r]

so we were right in the first place. you want 30 thousandths. three thousandths like your saying is way tight.

thirty thousandths(.030") is huge... you want three to four thousandths(.003"-.004")

i don't know i'm confusing myself. but thirty thousandths is what we run forged pistons in our race vw engines and more when were on the bottle...

maybe you are thinking of it like "thirty" ten-thousandths(.0030)... which is reduced to three thousandths (.003)... no automotive engine runs .030" bore clearance....thats a whole piston oversize

[oscarmayer]

if weisco said .030, that's what you go with. they mde the piston and thus know what it should have. actually pretty mcuh ever weisco should have .030 clearance.

[Nick_R_23]

thirty thousandths(.030") is huge... you want three to four thousandths(.003"-.004")

^This. I run .004" on anything aircooled with a Wiseco in it.

.030 is the 3rd bore size, which is wayyyy too much clearance.

Stock > 1st bore: .010 > 2nd bore: .020 > 3rd bore: .030 > etc

-Nick

[Dirtcrasher]

.030 or 30 thousands is double a spark plug gap

.003 or 3 thousandths is what your looking for or whatever Wiseco suggests.

Don't you guys remember your decimal points??

[tri-Z ripper]

what's this math stuff? jk decimal place very important!

[sbjones73]

ok. i called wiseco 2 times here. one last night and one today. one guy told me .003 and the other today told me .002- .0025. i am going to run the .003 clearance since i had this thing lock up on me once before.

thanks for all your help. i hope this thing will run ok. i cann't afford to rebuild it one more time. already got 2times my budget in it.

wish me luck!!!!!!!!!!

[oscarmayer]

ok sorry i meant .0030 forgot an extra 0. sorry.

[Dirtcrasher]

ok. i called wiseco 2 times here. one last night and one today. one guy told me .003 and the other today told me .002- .0025. i am going to run the .003 clearance since i had this thing lock up on me once before.

thanks for all your help. i hope this thing will run ok. i cann't afford to rebuild it one more time. already got 2times my budget in it.

wish me luck!!!!!!!!!!

Good luck!! and I too would go with the larger clearance (.003)......

Those 2 stroke air foolers need time to warm up and expand properly. I always sat and warmed it up a bit for about 1 minute and then rode easy for 3 or 4 minutes before I beat the snot out of it

WOW, imagine if you had asked them for .030?? machine shops don't always know pistons, but they know sizes very well!!

Turned and milled for quite a few years myself

[Nick_R_23]

I dont know the air cooled 250r cylinders very well, but if it has a bridged intake or exhaust, I would have those bridges chamfered out slightly more then the rest of the cylinder. Reason being is that those bridges tend to expand inward toward the piston and can cause seizure also.

-Nick

[sbjones73]

nope no bridge on the older air foolers.

yeah i messed up and said .030 and the machine shop was like "what, i hope that you meant .003," we both kind of laughed.

i should be done friday afternonn.

thanks guys.