Strange noise - Do I need more than a Top end?

[seitz729]

I'm starting to tear into my project Blaster. Summary: No history, won't start, has spark, low compression (60 psi). It was kicking over fine, however, I noticed that it seemed to lock up all of a sudden. Kick starter kind of froze. I put it in gear and gently rocked it free. It later, once it was free it made a strange noise last lasted on one or two revolutions of the crank. Hard to describe the noise, almost like a growling type of noise from within the crankcase. I haven't heard it again. So far I've got the jug removed. Every thing appears to be moving smoothly. I have about a 1/16" side to side play, but from what I've read doesn't appear to be much of a concern, no play up and down. I'll take some measurements tommorrow on the rest.

Is there anything I can check into regarding the lock up or the strange noise when kicking over the crank? any thoughts? Thanks in advance.

Dave

 

[motoman159]

i have no idea what your problem is because im stupid but i like your profile picture!! I:I

 

[Larry's Shee]

Pull your clutch cover and start inspecting everything real close

 

[dksix]

I has a similar lock up recently. The float stuck on my Tecate, filling the crankcase full of fuel. Kicker was locked up, try turning it over with the trike in gear. It freed up but never hit again. When I forced it to turn over (with the crankcase full of fuel) the fuel blew past the crankseal, filling the flywheel cover full of fuel shorting out all my electrical. I heard a funny noise right as it freed up, I guess it was fuel squirting through the side of the case. That was the moment I was finished with trying to keep 25 year old ATV's going with the very limited supply of 25 year old parts. A week later I bought an 01 Blaster and ended up here. It's only been 9 days ago, LOL. I liked it so much that I brought home an 04 last night.

 

[Blaaster]

The piston seems a little off centre to me, check if the circlip is still in the piston pin hole.

 

[seitz729]

Pull your clutch cover and start inspecting everything real close

pulled the cover off. everything turns smoothly. I think I will just keep my fingers crossed and rebuild the top end , unless anybody has any thoughts...

 

[Blaaster]

Is the circlip still in the piston, they have been known to pop out?

 

[seitz729]

Is the circlip still in the piston, they have been known to pop out?

Yup, both circlips were intact. Thanks,

 

[Blaaster]

Have you looked at the reeds,? Could have one of them broke or the holding screws fallen out.

In my book any grinding noises should be thourouly investigated, as it may happen again at 6,000 rpm, do I need to saymore?

 

[seitz729]

Have you looked at the reeds,? Could have one of them broke or the holding screws fallen out.

In my book any grinding noises should be thourouly investigated, as it may happen again at 6,000 rpm, do I need to saymore?

no. i hear ya, I picked up this blaster very cheap. I think there must be more than a top end problem. Here are the reeds. Screws intact. I think it looks okay.

My thought was if I can't identify anything, then to redo the top end and do a leak down test to further diagnos any problem. Would you guys recomend removing the other cover? I appreciate the feedback. My 2-stroke knowledge is pretty limited.

 

[Blaaster]

It has been known a screw to come loose, fall out and foul the flywheel.

I know it would be a major pain, as the motor is still in the bike, but I would be inverting it and flushing it out well to be sure that there is nothing in the crankcase..

Main bearings have also been known to throw a ball cage allowing balls to crowd, lock up and make grinding noises.

 

[blasterisfaster]

Just recently my blaster locked up because the magnet on the flywheel broke apart, but after it was freed up it turned like nothing ever happened. The magnet was all cracked up but it wouldnt have an issue untill the magnet decided to drop down and get lodged in there.

 

[Blaaster]

/\ /\ /\ Things do have a way of vibrating loose, especially if the previous repairer had not been introduced to Loctite.

 

[blastngo92]

Also if the previous owner used it regularly since 2001 and never once did a rebuild, hence my case lol

 

[seitz729]

Just recently my blaster locked up because the magnet on the flywheel broke apart, but after it was freed up it turned like nothing ever happened. The magnet was all cracked up but it wouldnt have an issue untill the magnet decided to drop down and get lodged in there.

After hearing these things, it sounds like it would be a good idea to open the stator side of the case and take a look inside as well.

 

[Blaaster]

Lets hope you find something wrong in there because the other place to look is the crankcase..

My fear is that the foreign object that was smashing about in the combustion chamber has not been expelled through the exhaust port.

It is very unlikely that it could have gone back through the transfers, but stranger things have happened.

On the lighter side, maybe the object has been expelled into the exhaust and all is well.

It may pay to pluck the motor out and flush out upside down whilst revolving the crank, maybe something will fall out.

This is turning out to be one of those suck it and see cases, I mean wether to split the cases or not.

Only you can deciede!

 

[seitz729]

It has been known a screw to come loose, fall out and foul the flywheel.

I know it would be a major pain, as the motor is still in the bike, but I would be inverting it and flushing it out well to be sure that there is nothing in the crankcase..

Main bearings have also been known to throw a ball cage allowing balls to crowd, lock up and make grinding noises.

pulled the engine to try to find anything out of the oridnary. Inverted the engine, went so far as to blow compressed air into the oil drain plug to flush out anything loose but found nothing. Would I be able to detect any main bearing issues with just a visual inspection. Still can't find anything that could have caused those funny noises prior to the rebuild. I'm guessing the frozen kick starter could have been due to the bike sitting for so long. I.D.K...

 

[blasterisfaster]

After hearing these things, it sounds like it would be a good idea to open the stator side of the case and take a look inside as well.

Shortly after i got the quad, like 4hours of riding or so is when it locked up and then thats when i decided to tear it down and inspect everything. I put all new seals, gaskets, and the few snap rings that i had to take off in it. I inspected all bearings and surfaces and all was in tip top shape. Previous owner claimed to have a new top end in it and it turned out true, whole topend looked brandnew. I also put a whole new(used) flywheel in. Now i feel safe about riding it now.

Blown motor = $$$ Peace of mind = Priceless