Motor Sound

[Lquad71]

So I had a bad rattling clanking sort of sound in the lower right side of my motor and I was told it was crank bearings. Being the end of the year I decided to do a full rebuild and my motor builder ended up replacing crank, bearings, a couple tranny gears, and the usual head stuff. But I got it back today and it is still making the same sound and im thinking it might be a water pump bearing so does anyone have any ideas of what it may possibly be? And if anyone could help me with the best way to remove the water pump bearing that would be great. Thanks.

[Lquad71]

or is it more likely a counter balancer shaft?

[xcracer416]

Originally posted by Lquad71
or is it more likely a counter balancer shaft?


i was thinking the same thing. counter balance bearings

[Lquad71]

do those go out more often than water pump

[xcracer416]

man they all can wear faster than others. there is no this bearing will go out faster than this bearing.

i have seen issues with the counter shaft bearings causing problems

[Lquad71]

I have to split cases to remove this correct?

[xcracer416]

well i would if it were mine, but rou might could check it from each side or take out the shaft

[d3ktrix]

Originally posted by Lquad71
I have to split cases to remove this correct?

IIRC you don't have to split the cases to replace the right side counter balance bearing.
You will need a bearing puller though to rock the bearing out.

All you have to remove is the right side case cover, the crank output gear and counter balancer gear.

I'd replace the water pump bearing while u are in there also.

If the bearing is bad enough to make noise like that, you will probably be able to jiggle the inner race with ur finger.

[DnB_racing]

you will have to remove both side covers to check all the bearings and seals properly, but you dont have to split the center cases
the bearings pop out pretty easy


if the bearings are bad enough to have a clanking noise, you might want to make sure all the surfaces are not worn (gears, weights, raceway)

if it was just a bearing you would feel the vibration first at your pegs and handle bars, but to make a noise either they are real bad and you ignored the early vibration thinking it was normal, or something is rubbing during the revolutions

during assembly be very sure of all timing marks, or you will be replacing the bearings again.. but after this you will be super sensitive to vibration,and noises... it happens to a lot of us, now when your riding you will feel and hear evey little thing... it becomes second nature, and you become in tune with your quad

[Lquad71]

my new motor builder did everything, and he did replace two tranny gears and after I called him about this he said its not counter balance bearings because he said he would have checked those, but I have just replaced the water pump bearing, and it felt it needed to be replaced so after replacing that I thought the problem would be fixed. Nope still does it.

So Ill be doing the counter balance bearings and if thats not it then i cant think of anything else in that area other than the oil pump, and if its the oil pump i think im in a lot of trouble.

[DnB_racing]

get an automotive stethoscope, and only run for a few seconds at a time and try to narrow down the loudest source point, and type of noise.. with practice you can actually tell the difference in the type of noises the different components make when failing,

I have to agree with the motor builder, im sure he checked the counter shaft bearings...any decent mechanic will be able to pick up a bad bearing.

now the oil pump:( that's a different monster all together the rotor tips could be slipping causing a noise... but I would start by pulling the side cases and turning over by hand with plug out and try isolating the source of the noise, but if I were you I would invest in a stethoscope,,, good luck:scary:

[d3ktrix]

I take a really big screw driver, put the tip on the engine, and the other end to your ear while cupping it with ur hand.

ha that sounds dirty, but its a poor mans stethoscope and works surprisingly well.

[Lquad71]

it turned out to be a really small crack in the case underneath the main bearing on the left side:(

[DnB_racing]

Originally posted by Lquad71
it turned out to be a really small crack in the case underneath the main bearing on the left side:( that bites the big one!!!!

what was hitting it to cause the noise?
it must have broke from something hitting, the crack is probly the end result of the part making contact, let us know what caused it when you open it up


good luck, dont try to go the cheap way ...it will allwasys cost more in the end, fix it right, and fix it all ....and be done with it,

[capecod400ex]

Originally posted by Lquad71
it turned out to be a really small crack in the case underneath the main bearing on the left side:(

The engine builder didn't notice this?