This is my 3rd blaster and first one with this problem. It starts and runs fine until it warms up. Once it is warm it will not idle it just stalls. As it stalling it emits a top end rattle/rapping/knocking sound. If you rev it a bit in will stay running and the rattle goes away. Thinking that maybe the crank seal is bad and leaning out I tried to add a little choke when it starts to stall which kills it quickly. The other think I noticed it that when you ride it hard it smokes a LOT, it is running on premix 32:1. So I am not sure if I have a crank seal problem or possable a balnce shaft issue causing the noise. Anyone have any idea? Thanks:-/
Engine problems
- Thread starter eman5oh
- Start date
Well guys I seized it up last night by running gout of gas with it tapped out in second gear. The back wheels locked right up. I bumped the idle up a bit and it seemed happy till she seized. Pulled the jug and the big end rod bearing has a lot of side to side play in it. I suspect that this was the cause of the noise.
Time some for new go fast goodies. Luckily parts for a blaster aren't really that expensive.... $159 for a new crank and rod assembly (new not rebuilt) isn't too bad. Overbore, clean up your top end a bit, replace the crank, leak check everything, and you'll be back up a running in no time.
what is a lot? because they should have some side to side play.
and running out of gas shouldn't really blow your engine up. and locked your back wheels up.
It's premix, so no gas mean no oil. I think it seized because it was revved up. By a lot I mean like 1/8 in side to side, I think the spec is around .030
i have run out before without that problem.. i suspect somethig else is to blame. make sure you leak test it when you get it back together.
no oil for a couple seconds will not cause the engine to seize. a buddy rode his banshee on straight gas for about 15 minutes before it finally blew.
and i have no clue on the specs for sideplay, but 1/8" does seem high.
i have ran out of gas plenty of times in 4th or 5th. usually it will just start to bog
and i have no clue on the specs for sideplay, but 1/8" does seem high.
i have ran out of gas plenty of times in 4th or 5th. usually it will just start to bog
If the piston was already damaged from flopping around and dragging because of the crank play it would have been a ticking time bomb and running at high RPM and then starving for fuel (and oil) could have sent it over the edge.
That is how I got my blaster. The PO did basically the same thing. High speed running and drained the tank. It starting sputtered, lost power, and slid the back wheels to a stop.
That is how I got my blaster. The PO did basically the same thing. High speed running and drained the tank. It starting sputtered, lost power, and slid the back wheels to a stop.
The top ring had rotated and the gap was not where the pin in piston hold s it. The pin that keeps the ring gaps put was damaged. Anyhow looking at doing a new crank piston and rings to get me back up and running. Can the crank be done without buying the special tools, ie the crankcase separation tool/puller stator puller and crankshaft installation tool? Also I see 3mm and 4mm stroker cranks, any one running one and is it any good?
You must have a flywheel puller. The other stuff is optional but nice. A +3 crank can be done without crankcase mods. The +4 requires some case relieving.
you can not rebuild a crank on your own, that is what he is asking about the tool. they have to be split then pressed together, better to leave that to a pro.
Sorry, shee. I think you are mistaken. A case splitter (crankcase separation tool/puller) is used to separate the case halves to remove the crank. A crankshaft installation tool pulls the crank into the case. He didn't say anything about rebuilding a crank.
use an automotive harmonic balancer puller and some long M8 bolts or studs to split the cases, i have a TUSK crank installer that works well for the reassembly. people have used a rubber hammer to do it, but its definitely not the preferred method. do yourself a favor and get an SMS stainless allen-head bolt kit.
to split cases i use:
flywheel puller
automotive harmonic balancer puller and M8x1.25 studs (had to make them, couldn't get them around me)
small hammer
large screwdriver
TUSK crank installer
i was able to do everything with all hand tools, on a kitchen table, then on my coffee table
to split cases i use:
flywheel puller
automotive harmonic balancer puller and M8x1.25 studs (had to make them, couldn't get them around me)
small hammer
large screwdriver
TUSK crank installer
i was able to do everything with all hand tools, on a kitchen table, then on my coffee table
Well I ordered up all the parts and a flywheel puller tool. I think I can machine some thing to install the crank. I ended up going with a stock stroke wesico crank kit and bearings. I just bought his blaster two days ago so this sucks. At least the motor will be like new again. I think it may have had a bad crank seal that caused it lean up a bit combined with running out of gas further leaning it and lack of oil. I hope that is the cause. In any case i will have new piston and rings new crank, bearings, and seals so it should run like top again. I will be cleaning the carb while it is down as well.
