they would make a noise for a while then maybe give up but i drove my vr4 legnum for weeks till it died
gadgit3,
Nov 23, 8:47am
No warning really. Cause once you can hear the knock then there is crank damage that will need sorting before a new set of B.E shells can go in.
intrade,
Nov 23, 8:48am
knocking noises esepcially when you take off at intersections. 91 octane fuel is the best way to destroy bigends. and ignoring the nock of death at intersections .
paul861,
Nov 23, 10:34am
what planet are you on! the fuel used in no way effects big end bearings.
strobo,
Nov 23, 10:38am
# 4! utter bollocks !
intrade,
Nov 23, 11:28am
yes it does you morons just got not a single clue how a moderninternal combustion engine works. The anti knocksender will retard the timing untill it reaches its limmit and then it starts pinking whacking the bigends thats what the pinking sound is. the sound of damage to your bearing shells.
mechnificent,
Nov 23, 12:02pm
Ha. I was about to sat that for once I agree with Intrade. till that last post.
Unless Intrade means that the pinking sound is the sound of damage BEING DONE TO the bearing shells!
Low octane fuel can cause pinking, and if they pink, that can damage the bearings and the rings. the pinking noise itself though is not made by the bearings. The pinking noise is fuel exploding. The bearings suffer because of the explosive effect. One is the cause, the other is the result.
mechnificent,
Nov 23, 12:07pm
The most usual symptoms of worn bearings used to be the oil light flashing on at idle and when the motor was warm, or the knocking sound when you were just taking off. A good way to test for worn bearings or low oil pressure is to almost stall the motor when it's warm by riding the clutch with the brakes on. The combination of low revs(the lower the better), which means the oil pump doesn't work very well, and the heavy load on the bearings, will often show up the deep knock sound.
phillip.weston,
Nov 23, 12:08pm
yes pinking doesn't do good for the big ends but a healthy set of big ends will handle it fine. I would have thought the piston crowns and ring lands would have given away long before big ends due to pinking.
unbeatabull,
Nov 23, 12:09pm
This. Pinking is usually pre-detonation or uncontrolled detonation, the noise isnt the bearings, moreso whats happening inside the cylinder.
mechnificent,
Nov 23, 12:26pm
Depends on the motor Philip. some have weak bearings, or thin oil perhaps. but both suffer for sure.
mechnificent,
Nov 23, 12:26pm
Depends on the motor Philip. some have weak bearings, or thin oil perhaps. but both suffer for sure. (Edit) Actually, thinking about it a bit more. you are right, the rings do generally go well before the bearings actually shit themselves. When you pull the motor to bits though the signs are there on the bearings. little holes in the white-metal huh, pits with square edges to them.
mechnificent,
Nov 23, 12:27pm
Yeah that's right Unbeatabull.
splinter67,
Nov 23, 12:42pm
OMG I agree with you
splinter67,
Nov 23, 12:42pm
OMG I agree with you
OP yes they give a warning the knocking is it followed by it going quiet then the conrod lets go usually making a rather large hole in your block and wallet
chebry,
Nov 23, 1:37pm
Preignition produces a pinking soundand will lead to piston failure if ignored long enough big ends! nar but its a shrewd move to throw a set in if the engines in bits
elect70,
Nov 23, 1:43pm
In that case intrade Id better stop using 91 in my 8.5 :1 crdisco .althoughstates use 91 on petrolfiller flap .
chebry,
Nov 23, 1:48pm
Havent had much to do with bearings eh the bearing metal breaking up is from hammering ie its been beyond spec for some time none of that is caused by detonation which causes upper cylinder damage broken rings cracked pistons. Where the noise is the damage will be too
the_chooky,
Nov 23, 2:10pm
I cringe when I hear cars pinging.I'm sure some drivers have got no idea what damage they're doing to the motor by running 91 and letting it ping it's head off.
mechnificent,
Nov 23, 2:14pm
ha Chebry. you are a funny guy. sure I've had a lot to do with bearings. I was probably changing bearings while your mother was changing your diapers.
intrade,
Nov 23, 2:34pm
yes thats exactly what i mean the sound is a indicator for damage on its way.
intrade,
Nov 23, 2:40pm
well do you hear it pink if it does then its not made to run 91 ocaten and you should immidietly fill high octane to bring the octane level back up of whats left in the tank. verry few cars are made to run 91 octane and then there is the problem that 91 is probably only 88 to 90 octane once you got it in your tankand 96 ends up being 94 and so on depending how old the fuel already is.
tim41,
Nov 23, 3:05pm
youll be fine as long as you stay away from intersections by the look of it
splinter67,
Nov 23, 3:08pm
you must be retired then
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