250r Seized!!

[caleb200x]

My friend was riding his 85' 250r at my house the other day, and about 15 minutes into the ride his piston seized inside his motor. It won't turn over for nothing! Any suggestions on what he will have to do to get it free again? And also what all new parts is he going to HAVE to have? He said he was running the gas 20:1. But he was also running the cheap Wal-mart oil too. He wants me to help him get it going again and I was wondering if there was any tricks to make this easier?

Thanks alot guys!!

Caleb

[DeePa]

get dirty, pull the motor, and see why and what it needs....then we can help you more.

expect to get a bore and hone, new piston and rings, possibly new wrist pin...

new head gasket, and check the rod while you have it apart.

Sometimes you can pull the carb and reed cage off, and exhaust flange, and get a look at the piston.

mike

[crackshot]

He said he was running the gas 20:1. But he was also running the cheap Wal-mart oil too

That's what did it, I can assure you of that.
89 cent oil is going to end up costing 200.00 in repairs.

[3WW Star-Yamahondaman]

That's what did it, I can assure you of that.
89 cent oil is going to end up costing 200.00 in repairs.

HE IS RIGHT !!!! along with ......... ( NOT ) Checking the Jetting,Plug"Heat" Range and Prolly useing 87 OCTAIN ??? and Maybe running FIVE MILES WIDE OPEN ?

[jason 32]

well guys 20-1 ir richer on oil and thats what you need wide open-
not nessaserily 20 -thats what the air coolers ran stock
get a manuel -
might have been time for a new ring job and broke a ring?
if so see how bad,check the bottom end for broken parts
take the head off see if there is damage,put it in gear push it back and forth see if it moves at all ,it might be the rod berring?
you can use a piece of wood and the piston down,either way it has to come off
let us know some more

[traxxasx]

One time when a go kart engine seized this guy asked me to get it tunning under 20 minutes, and he would give me 30$. Well i let it cool for a min then took the plug out. Poured some engine oil in the hole, let it sit for a secound. Then i took one of those screwdrivers with a fixed but size on it, i dont know what there called, then bet on the piston a lil not to hard. then pull the pullstart really hard and beat some more then it just came loose. After that it ran normal and is still running strong today since last year. Lol he said under 20 minutes no matter what.

[hoser]

Engines don't lock up without a reason, before you begin your CSI you need to pressure test that engine to ensure it does not have a air leak if you just rip it apart in a hurry to see what make it stop you might destroy important evidence that will prevent you from getting at the root cause of the failure, its also a good idea to pressure test a engine before you take it apart if your just doing a basic rebuild. http://12.215.122.222/rebuild1.htm