I have a 1996 yamaha blaster and i was riding the other day and was a bout to climb a hill and i herd a nasty knocking sound from my engine so i shut it off right away and then tried to start it again it had no compression. So i took out my brand new sprakplug to find that the piston was hitting the bottom of it. Has this ever happened to anyone and can someone help me to fix this like what parts i need and stuff. I really miss riding and want to get it fixed ASAP
blaster problem
- Thread starter edfromnj
- Start date
if the piston is broke, yes you can buy a new one, but first check your cylinder wall to make sure it isn't bad.
as for the rod bearing, it isn't that simple. i suggest taking it apart first. your rod could be messed up and you will need a new crank. hard to tell. dont buy any parts till you take it apart.
as for the rod bearing, it isn't that simple. i suggest taking it apart first. your rod could be messed up and you will need a new crank. hard to tell. dont buy any parts till you take it apart.
lots of pics, piston, cylinder walls, lot's of different angles of the cylinder walls, head, crank, and tell us how much play the rod has in it. does it move up and down at all on the crank. stuff like that will help us help you.
well guys took it apart last night and found out all i need is a new piston so its like 80 for a good piston nothing is wrong with anything else. cylinder walls are nice and smooth and the crankshaft bearings a seam ok uiam replaceing them just in case. thanks everyone for your help and i will post pictures to day of the cylinder walls and piston and all that other good stuff.
x2 on this, if you just put another piston in without diagnosing the original problem its most likely going to happen again.
Something else is wrong with it. The piston doesn't hit the plug for the hell of it.take the crank and rod to a local repair shop and have them look at it. This is an engine. You can't be 090% sure on it. You have to be 100% sure or it's going to come back to bite you in the wallet.
That's 90 percent.it keeps changing it on me.
That's 90 percent.it keeps changing it on me.
so what does the piston look like? is there damage to the head? if something contacted the spark plug there was debris in there, and that's a bad thing.
as far as crank bearings, you need to pull the stator cover (the left side as you're sitting on the quad) and see if you can move the flywheel up and down or back and forth, also can you move the big end bearing up/down at all? what is the side play in it?
and then after you get the thing back together you really need to check to make sure that there are no air leaks. to do this buy or make a leakdown tester.
you also need to have that cylinder honed so that your new rings will seat again. you also need to check piston to wall clearance to avoid broken skirts
as far as crank bearings, you need to pull the stator cover (the left side as you're sitting on the quad) and see if you can move the flywheel up and down or back and forth, also can you move the big end bearing up/down at all? what is the side play in it?
and then after you get the thing back together you really need to check to make sure that there are no air leaks. to do this buy or make a leakdown tester.
you also need to have that cylinder honed so that your new rings will seat again. you also need to check piston to wall clearance to avoid broken skirts
sounds like you are starting to discover the problems. are you premixing or still using the oil injection. if you are premixing i would say you had a piston meltdown bc of an airleak not lack of oil. post pics man it will really help
i premix and yes it was an air problem with my reeds so i have to get new reeds and that black rubber gasket that hooks the carb up to the reed is also bad. Sorry i though it was my piston hitting my sparkplug but i was wrong i have the pics and am putting them up today.
