crank bearings

[wsuwrhr]

My father in law rebuilds transmissions in his garage for a living. He has a press and a splitter. Is it pretty straight forward to install the new ones? Do they just go back onto the crank until they hit a physical limit?

Yes.

But they have pin locations and have to go back the same way of course.

 

[D-Roc]

I use yamaha bearings on my crank. they cost more but the best stuff always does. i like to have good stuff. i removed and replaced them myself. the bearing hits a shoulder or a lip once pressed on all the way.

 

[tshank123]

I think we can do it. Doesn't sound too bad. WFO, sending a PM.

 

[SUPERTUNE]

I think we can do it. Doesn't sound too bad. WFO, sending a PM.

Go for it, not that hard to do.
You can heat the bearings to 175 degrees for 15 min. in a home oven and if you stand the crank up (on a pipe or old sleeve) and the bearing will drop right on and seat to the bottom shoulder, eliminating any press work going back on.

 

[Freakrider]

I find this post to be quite funny as the Nachi brand bearings would be coming from where,yep you guessed it WSM,its the only brand of bearings they sell.:thinkerg:

I have been told that WSM uses different suppliers and they can't say for sure they will be Nachi bearings or different ones...

 

[augustaf]

My father in law rebuilds transmissions in his garage for a living. He has a press and a splitter. Is it pretty straight forward to install the new ones? Do they just go back onto the crank until they hit a physical limit?

That's right, they press against a shoulder. I've had a conservative upbringing and prefer to heat the bearings in oil at about 350 deg. Then you just stick them on there, maybe with a light tap. The thing that worries me though is: how good are the rods? The front bearings on a Yam crank are pretty much bullet proof (not so the rear one). Has this crank been exposed to water?

 

[tshank123]

I don't think it was exposed to water. The bearings aren't horrible either. They are just making a slight ammount of noise which I think maybe just from normal wear and tear. The middle bearings sound perfect. The rod bearings look good too.

 

[Crab]

when we un-bag the sbt crank this week i will post the brand of bearings they use

 

[WFO Speedracer]

Bearings were ordered today,I should see them here in about three days

 

[2XLR8]

I have a feeling those bearings will have the groove around them and a CHINA stamped on them.

 

[WFO Speedracer]

I have a feeling those bearings will have the groove around them and a CHINA stamped on them.

Care to put your money where your mouth is? :cool2:

 

[2XLR8]

The Nachi ones I have been able to get don't have holes for the pins. If you can get them I will buy two of them. Let me know and maybe post a pic. Let me know if I am wrong, it is August and I am due to be wrong. In this case I hope I am.

 

[WFO Speedracer]

The Nachi ones I have been able to get don't have holes for the pins. If you can get them I will buy two of them. Let me know and maybe post a pic. Let me know if I am wrong, it is August and I am due to be wrong. In this case I hope I am.

Truefully it makes no difference if the bearing has a groove for an o-ring or a pin,both perform the same function,we will see Friday when they get here I guess.

 

[Big Kahuna]

Terry, would have thought wsm uses china or taiwan bearings !! well blow me down...lol...I would not use wsm crank seals....only oem

that is good to know that wsm are Japan steel bearings...I would buy them

The Standard WSM seals are junk. The premium seals are good. I have used them many times with no problems or leaks. I have had OEM Leak.

 

[tshank123]

Truefully it makes no difference if the bearing has a groove for an o-ring or a pin,both perform the same function,we will see Friday when they get here I guess.

Are you saying these might not have holes for the pins?

 

[wsuwrhr]

If I understand you correctly, I disagree.

The bearings DO use the pins to line up holes to get residual drip oil from the transfer area of the cases.

Whether the motor truely needs them or not may be debatable, I don't know, but I have faith in Yamaha's engineering, if I can't justify a change, I'll trust that there is a damn good reason for it being there.

Kinda like, Why are there two seals on the PTO side and one on the mag side? Crank flex at the coupler maybe, no damn reason maybe? I'll trust there is a good reason why and leave it there.

The groove sets the crank in place to align it.

My advice again to Tshank is to use OEM sh it and not try and save money on a part spins 8000 RPMS and has the potential to wipe out the whole motor if it fails.

Brian

Truefully it makes no difference if the bearing has a groove for an o-ring or a pin,both perform the same function,we will see Friday when they get here I guess.

 

[WFO Speedracer]

Are you saying these might not have holes for the pins?

If the bearings are not correct I will just send them back,I am not in the habit of selling incorrect parts also they charge me nothing to send them back,the kind of groove I was referring to are the ones like on the Rotax engines that accept an o-ring,the o-ring compresses slightly as the cases are bolted together holding the bearings in place.The bearings I have seen from WSM looked just like OEM bearings,WSM used to build crankshafts in house under the names New York crankshaft and USA shortblock,they might just know a thing or two about sourcing crankshaft bearings.

 

[Big Kahuna]

If the bearings are not correct I will just send them back,I am not in the habit of selling incorrect parts also they charge me nothing to send them back,the kind of groove I was referring to are the ones like on the Rotax engines that accept an o-ring,the o-ring compresses slightly as the cases are bolted together holding the bearings in place.The bearings I have seen from WSM looked just like OEM bearings,WSM used to build crankshafts in house under the names New York crankshaft and USA shortblock,they might just know a thing or two about sourcing crankshaft bearings.

I ran one of their cranks from 2004 to 2007. Put alot of hard hours on it until the bearing race (cages) let go.

 

[2XLR8]

The grooves I am talking about is to supply oil into the bearing. I could be wrong but I think the oil hole even on the oem bearings dont not line up with the hole in the case. The wsm bearings have the groove in them and that allows oil to be fed into the bearing. I have a feeling it says nachi in the catalog but you get bearings stamped china on them and with the grooved machined into them. I hope I am wrong.

 

[WFO Speedracer]

The grooves I am talking about is to supply oil into the bearing. I could be wrong but I think the oil hole even on the oem bearings dont not line up with the hole in the case. The wsm bearings have the groove in them and that allows oil to be fed into the bearing. I have a feeling it says nachi in the catalog but you get bearings stamped china on them and with the grooved machined into them. I hope I am wrong.

I will know this afternoon when they get here,if they are correct they will ship out,if not they will go back,pretty simple.