Horizons Unlimited - The HUBB

Horizons Unlimited - The HUBB (https://www.horizonsunlimited.com/hubb/)
-   Yamaha Tech (https://www.horizonsunlimited.com/hubb/yamaha-tech/)
-   -   engine rattle (https://www.horizonsunlimited.com/hubb/yamaha-tech/engine-rattle-22071)

richardc 30 Jun 2006 00:08

engine rattle
 
Hello everyone, I have a 1985 Srx6, a jap import. It runs nicely except for a rattle in the engine thats difficult to pinpoint. I have read the other threads on cam-chain noises but this rattle (sounds like a ball bearing in a jar) is comming from between the oil filter and clutch drum....I think? It comes and goes, but is audible mostly under load...like really advanced ignition timing. But the spark plug shows no evidence of this.
I didnt want to strip the engine without diagnosing first. Any ideas?
regards,
Richard.

skip 2 Jul 2006 19:48

Hi Mate
Best to wip the side cove off and have a look, sounds like somthing may have come lose. Better safe than sorry. Skip

richardc 4 Jul 2006 10:49

engine rattle still..but spare Oring!
 
Thanks for the reply Skip, I've just screwed it back together. I found a loose adjuster in the clutch pressure plate. The hexagonal shaft of the adjuster was protruding too far so the lock nut wasn't clamping hard against the pressure plate but against the shaft...if that makes any sense.
The end result is a nice smooth clutch, one less rattle...but the main one is still there!!
The engine is nice and quiet at idle but this knocking sound comes in at around 2,000rpm as i lift the revs...then goes away around 3,000rpm. When I ride it the rattle gets worse under load...
Anyone had any experience with balance shaft related bits? bearings, gears, etc???

I also found an O-ring (about 10mm dia) floating in my drained oil. God knows where thats come from..it looks unused?

winmac 4 Jul 2006 23:07

O-ring could be form the oil filter cover, lower bolt

skip 5 Jul 2006 01:43

Hi mate
Dose the engine use much oil, with out hearing it it sounds a bit like the small end ( piston to con rod pin) this will rattle like the timing is out if its worn or has been run low on oil, but as i said i would need to hear it, what dose the plug look like after a good run, dose the rattle get louder as the engine gets hotter. It may be worth taking the side cover off and making sure that the timing chain is ok. Let us know how you get on. Skip

richardc 5 Jul 2006 10:59

-->"O-ring could be form the oil filter cover, lower bolt"
thanks Winmac, the manual I downloaded doesen't show an o-ring here? is this under oil-filter cover or between clutch-cover and engine case? I have refitted the clutch cover with a new gasket...no leaks.

-->Hi Skip, rattle is louder than little-end noises I have heard in the past and appears to come from the bottom of the motor around the counter balance shaft area on the r/h side. Could be big-end I suppose ?(ouch!), but its quiet at idle. Bike has 29,000kms on it, engine uses very little oil, plug looks pretty clean..I've put 6,000kms on the bike since i bought it and its no worse.
regards,
Richard.

skip 9 Jul 2006 01:04

Hi Mate
On rebuilding my engine i found a very worn balence shaft bearing, it had made no noise at all but the conrod the reason for the rebuild rattled like a kid with a tin drum.
It may be worth checking the bearing on the back of the clutch basket if this is worn it can allow the gear teeth to rattle a bit.
A long shot but there is nothing floating around the oil pump strainer, i found the tag from a locking washer under a strainner once, as the oil was sucked up it sounded like the ticking of a clock, as i said its a long shot.
It may be worth getting some one to have a listen before you go any further.
Let us know how you get Skip.

PS Two days ago i had a slight rattle on my engine, it cut 20kms from Buenos Aires on inspection i found a lump out of the piston and a load of broken rings great

Moto Zulu 9 Jul 2006 08:36

crankshaft
 
Hi,

did you check the nut on the crankshaft? That ones like sometimes to come lose. You dont realy see it. You have to move on the gears crank/balancer a little bit. Than you maybe see that the shaft ist standing and the gear on the crankshaft is moving.

Or the piston can also make some noise

regards

Thomas


All times are GMT +1. The time now is 11:54.


vB.Sponsors