Crank Bearing Damaged, Crank Replacement?

[j_fitz7]

I badly mangled my crank shaft bearing attempting to removed a leaky crank shaft seal.

Here are the options I can think of, I am no expert and some of the forum's expertiese is needed!:

1) buy a new crank on Ebay and split the case to install
2) split the cases and have bearing replaced on my crank (sounds expensive), more down time to have crank reworked.
3) buy a stock crank form someone around here who can verify it is in good shape, install?
4) Shear off the damaged ball bearing "sleve" and pray engine does not explode (dosen't sound safe!)

The picture shows damage to the individual ball "sleve" structure caused by my attempt to drive the seal out with screws threaded into the old seal. Look at the pictures around 7 o'clock position.

 

[Big T]

Since it's an end bearng, #2 is your best option. A machine shop should be able to press the damaged bearing off and a new bearing on.

You'll have to split the cases no matter which way you go.

 

[Suzuki mad]

Oh I say that doesn't look good!

Best option is using your crank and having new bearings fitted. You know the state of the crank and its condition.

Which ever of the options you have to split the cases so why put an unknown into your engine?

I know its a lot to strip the engine complete in work time but you can make one hell of a good motor out of it.

Suzuki mad.

 

[Dave8338]

Yep...do it right! If you don't, it will leave you wishing you had, most likely, too far from home to push it........

 

[j_fitz7]

What would it cost to have a new bearing pressed onto my crank?

What would it cost to have a new bearing pressed onto my crank?

Alpha sports shows the bearing cost:


Part# 09262-30033Desc B1 30X72X19 BEAPrice 28.82

 

[Dave8338]

It all depends on the shop and what mood they're in. It wouldn't hurt to call around and get a few estimates.

 

[Suzuki mad]

Here in the Uk there are several companies who would do this sort of job for the cost of the bearing and there time.

One company used to be Suzuki's main crank repair company during the 1970's and 80's and still operate a full suzuki repair service. From all accounts a very good job.

So to my point, there must be an equivalent company where you are who can do the same thing.

Do you have classic magazines which classified adverts on the back pages for repairs, that's were these guys advertise.

Suzuki mad.

 

[j_fitz7]

Engine Rebuild

Engine Rebuild

What else should i do while I am in there? I found this list on the Old Q & A. The engine had 70K+ on it and ran just fine minus the oil leak I should have never tried to fix.

While you are there you should check:
1. Camchain.
2. Camchain sliders.
3. Cylinder diameter. (if it is over service limit you should rebore and install new, ovesized pistons)
4. Pistons, piston rings and piston bearings. In any case it is better to install new piston rings, othewise you will loose compression.
5. Valve guides.
6. Camshaft bearings.
7. When puting back the head, tight the nuts following rigourosly the manual instructions. Check torque on head nuts after 1000 Km. If you dont do that, you will end up with another oil leak.
If you value your money more then your time, you can try not to install new piston rings. I have done this myself when I was young and careless (and did not have much money). It worked fine, but I would not suggest it to anyone else.


-J

 

[j_fitz7]

Use as is?

Use as is?

I've been thinking more about the situation. The only real damage i can see is to the sleve that cradles the balls in the races.

I have been considering sealing everything up and trying to run it as is. I would change the oil right away to collect the metal shavings and monitor the engine for the sounds and vibrations which might indiacte the crank bearing is damaged.


Can I get anyone on the GSResources to agree with this plan, or does it seem too risky? Why?

Thanks.

 

[CA180]

Sounds like your asking for trouble... And wanting to destroy the rest of the motor. I wont take much for that roller bearing to come apart.

 

[rosco15]

I would be afraid for something to happen to the crank. If you break the crank it could take out the entire motor. cases, valves, head block. I would fix it right.

 

[t3rmin]

I've been thinking more about the situation. The only real damage i can see is to the sleve that cradles the balls in the races.

I have been considering sealing everything up and trying to run it as is. I would change the oil right away to collect the metal shavings and monitor the engine for the sounds and vibrations which might indiacte the crank bearing is damaged.


Can I get anyone on the GSResources to agree with this plan, or does it seem too risky? Why?

Thanks.

It's hard to tell from the picture exactly where those metal shards originate. But if neither the balls nor the inner surface of the race is damaged, and you feel the whole thing has good integrity still, I don't see why you couldn't run it as-is.

 

[j_fitz7]

The damage resulted from threading two drywall screws into the seal in an attempt to drive it out. The points of the screws bore several holes in the soft metal sleve. In one location the sleve no longer connects over the ball and i had peeled it back in this picture. At first glance the races and balls seem ok, but it is hard to say for sure.

I was thinking about just bending the portion of the sleve that is bent out at 90 deg back over its ball and putting in the new crank seal and starting it up!

Any more thoughts?

 

[Guest]

That bearing carries alot of load. Don't do it. Split the cases. The crank will have to be removed and a new bearing put on. Sorry for the bad news.

 

[CA180]

Dont let this come across wrong. I dont want to offend you...

Its your bike, your going to do what you want any ways. Just be warned of the possibilty of EXTENSIVE damage.... Other than that, your good to go! :-D


Just dont be misled. There are no absolutes. Crap, you could take it to a shop, have them replace the bearing and it could still grenade on you! But some misfortunes are easily avoidable.

 

[Guest]

Treat the ole girl right....bite the bullet, split the cases, and do whatever is neccessary before any more serious damage occurs! She will thank you for it in the long run.:-D

 

[j_fitz7]

Thanks for the advice I needed to hear it!

Thanks for the advice I needed to hear it!

Im going to split the cases. What else should i check out while i am in there?

Replace piston rings, replace gaslets and o-rings, examine oil pump, cam chain, sliders and valve heads and seats as a minimum?

 

[Dave8338]

I've been thinking more about the situation. The only real damage i can see is to the sleve that cradles the balls in the races.

I have been considering sealing everything up and trying to run it as is. I would change the oil right away to collect the metal shavings and monitor the engine for the sounds and vibrations which might indiacte the crank bearing is damaged.


Can I get anyone on the GSResources to agree with this plan, or does it seem too risky? Why?

Thanks.

IT WON'T LAST, and what part of that motor do you want impaled in your leg(s) when it does let go? :shock:

 

[j_fitz7]

Anyone think that this bearing could be replaced by just dropping the bottom half of the case off and swapping out the bearing by pulling the pistons down in the bores?

I just talked to a local guy mechanic who said he would try that first and proceed with the full rebuild if that was not secuessful.

 

[t3rmin]

Anyone think that this bearing could be replaced by just dropping the bottom half of the case off and swapping out the bearing by pulling the pistons down in the bores?

I just talked to a local guy mechanic who said he would try that first and proceed with the full rebuild if that was not secuessful.

That's what I was thinking. Motor upside-down, bottom case-half off, pull off the cam chain tensioner and you might have enough slack to get a puller on that bearing...?