Need help - rattling noise when throttling

[Archania]

I check my bike before i took off to my friends house. there is an oil leak from one of the screws on the top of the crankcase by the oil plug. There was oil in it according to the site glass.
I left for the 57 mile one way trip.
On my way home, the oil light came on and it died.
Tried to restart it but got dim lights. Had a jump from a guy passing by. worked.. on my way again...
Starting hearing a rattling/nocking noise. Not sure if its from the crankcase or the cylinder head.
Any ideas at all... please help.
I love this bike and very upset over it.. considering i was pushing it for about a mile.
I ride it just about everyday to work.. and going on a trip in the beginning of august.

[76FJ55]

I'm not sure what bike you have, but it doesn't sound promising. what was the oil lever when you finally got it home? My first guess is that it's time to source another engine. As to weather it is top end or bottom end... the 4 valve heads are prone to excessive wear and deterioration from low over heated or lack of oil pressure. however if it is knocking I would guess rods. the only way to know is to start tearing it down and seeing what you find.

[bonanzadave]

I check my bike before i took off to my friends house. there is an oil leak from one of the screws on the top of the crankcase by the oil plug. There was oil in it according to the site glass.

Definetly check the oil level. You could have filled the crankcase with gas via a bad petcock hence the oil leak.

[BassCliff]

Hi Mr. Archania,

This doesn't sound good. When the oil light comes on, that means there is no oil pressure, which means there is no oil. Running your engine with no oil is very, very bad.

Fill up the oil to the proper level and test. Hope for the best. Keep us informed.

Thank you for your indulgence,

BassCliff

[psyguy]

you may have several unrelated issues
check your charging system
make sure the oil level in the sight glass is correct and record the use of oil
pay attention to the noise from the engine and record the details of when it happens and what does it sound like (knocking, rattle, buzz, when warm or cold, when under load, at idle, at high/low rpm, etc etc)

[Archania]

well it was out of oil when it stopped.
I put more oil in and it was filled 1/2 way.
It sounds like a knocking noise. It idles fine, just when i apply the throttle, it starts.
Shifts fine also.
i'm still confused on why it would leak oil from under the screw.
I'll be taking it apart this week and see.
Any ideas what to look for? or just take it down and see if something is bent/twisted/ broken?

I do have the clymer book also. But it doesn't really specify what to check.. just what might have caused it.

[Archania]

Just so that I am on the correct page here.
When I do start taking things apart.. besides taking pics of everything.. I need to also get NEW gaskets/seals etc. to put it all back together.
Correct?
And of course before I take anything apart.. drain gas/ oil.

[DanTheMan]

This sounds like an oil leak from the base gasket for the cylinder jug. Also sounds like you've most likely got a blown head gasket which would cause that excessive oil consumption.
My Rx? Buy an engine overhaul gasket set, pull the valve cover, head and cylinders, follow the disassembly/assembly instructions in one of the available manuals, hope you didn't hurt the con-rods and mains, put it back together, it'll work. Mine suffered the same way 15 miles from home, I rode it home with it soaking my right leg in oil.....no major damage, still riding, and I have put 9k mi. on it since. These engines are tough, but if you run them out oil, like any other engine, you're SOL when that happens.

I check my bike before i took off to my friends house. there is an oil leak from one of the screws on the top of the crankcase by the oil plug. There was oil in it according to the site glass.
I left for the 57 mile one way trip.
On my way home, the oil light came on and it died.
Tried to restart it but got dim lights. Had a jump from a guy passing by. worked.. on my way again...
Starting hearing a rattling/nocking noise. Not sure if its from the crankcase or the cylinder head.
Any ideas at all... please help.
I love this bike and very upset over it.. considering i was pushing it for about a mile.
I ride it just about everyday to work.. and going on a trip in the beginning of august.

[DanTheMan]

Don't need to drain gas if your fuel petcock operates correctly (you do need to remove the gas tank). Drain the oil when the job is done, the old oil will catch any particles that fall into the pan and will drain out with it. If you're going to pull the pan to check the con-rods and mains, then yes, drain the oil.

Just so that I am on the correct page here.
When I do start taking things apart.. besides taking pics of everything.. I need to also get NEW gaskets/seals etc. to put it all back together.
Correct?
And of course before I take anything apart.. drain gas/ oil.

[Archania]

I took off the carbs and air box last night.
The air box has a film of oil all in it. I don't think thats a good thing.
Tonight will attempt to look at taking the heads off.

[psyguy]

a "knocking" at high revs is usually related to crankshaft probs, no good
make sure to inspect for any play at the connecting rods

however, what you're hearing may not be that kind of knocking... you'd need an experienced EAR to be able to tell you more about your prob, going by the sound only

[Archania]

i hope its not.. cause from what i understand.. if thats the issue.. then it is too costly to repair - thus bike shopping anew.
Hopefully tonight i will have a better understanding of what is going on...

[Archania]

Update:
With the help of 83Gsrider, we found out that the #4 piston is cracked and the ring is busted.
The housing seems to be alright.. no big gashes in it nor lips. So hone(sp?) it out slightly. If need be. order all 4 new pistons and rebore. Cost is a factor here... but will do it if need be. Really don't want to invest in a new bike if i can get her running again for a 1/3 the cost. meaning 500 for repair instead of 1500 for a new bike with possible issues since not knowing the po take of the bike.
Going to order new piston, gasket set, and put her back together and see.
And of course clean the crap out of it before.. no reason not to now since everything is basically apart enough to clean the engine properly.

pics coming tonight that is if verizon decides to work at my place.

[bleeble]

Just FYI, I've seen used piston sets on ebay go unsold for $10-20 plus shipping. Might as well look into it. :-)

[psyguy]

so, what about the connecting rods?