Main bearings (2010)

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Hello,

Is there any way to get the inner race of the main bearings from the crank without a special puller ?
The race looks absolutely Ok but my new bearings (NJ306E) have a different diammeter than the old ones (3nu06) so i cannot use the new bearing with he old inner race
 
Mick in his DVD says you can beat it off with a chisel if you are real careful. Take note that there is a raised edge on the journal, so don't go sticking something real sharp in there or you will mess up that flat edge. Of course you will beat up the bearing getting it off, but you have a new one. I got mine off that way. Take it real slow and alternate your whacks. Look at your timing side journal, the bearing probably came off the crank on that side and you will see what I mean about the raised area the inner bearing rests on. Make a chisel with a flat side and use that flat side against the crank (kind of like a wood chisel, but not nearly so sharp). Keep putting things under the chisel as it starts coming off.

I would have taken it to a shop if I could have found one with a bearing puller rather that beating on it but buying that puller is real expensive.

Dave
69S
 
Thanks Dave i will try that but will it really work ?
The surface is hard as hell !!!! :twisted:
 
Use a mini angle grinder (very carefully!) to grind about half way through then split with a chisel,
Dave.
 
twinshocker said:
Hello,

Is there any way to get the inner race of the main bearings from the crank without a special puller ?
The race looks absolutely Ok but my new bearings (NJ306E) have a different diammeter than the old ones (3nu06) so i cannot use the new bearing with he old inner race

Step 1 - sharpen a chisel
Step 2 - heat up the inner race with a torch
Step 3 - tap the chisel between the race and the cheek of the crank

Once you heat up the race, it doesn't take much to get a sharp chisel between the race and the cheek. You should be able to move the race enough to get a regular puller behind the race. The "special" pullers are pretty cheap if you can get one of the Chinese units.

OR go to a vintage VW garage and they'll pull that race off in about .2 seconds.
 
Builder,
With a sharp chisel, you risk damaging the cheek on the crank. That is why I said "don't use a real sharp chisel". I know, I ended up with a bunch of little marks on the outside of the cheek and I had to take a file to the cheek. You don't want to be beating on the cheek, just the flat surface of the crank outside the cheek. Like I say, make a chisel flat on one side and tapered on the other, not too sharp.

Main bearings (2010)


Twinshocker,
Yes, it can be done. It takes a while and heat would probably help, take your time, I did it. Cutting it off would work too, if you don't damage the crank.

Dave
69S
 

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Thank you guys for all the hints i finally got that thing off.

I grinded a little groove into the surface with a small pneumatic drill and a tungsten-type very hard cutter.
Then i could put the chisel onto that edge and hammer it of a little bit until i could fit a two-arm puller.

Next question : I took the crankshaft apert to clean it in the middle. Is there any trueing required after bolting it together again or can i just mount it into the cranccase ? How much sideplay should this crankshaft have ?
 
DogT said:
Builder,
With a sharp chisel, you risk damaging the cheek on the crank. That is why I said "don't use a real sharp chisel".

Main bearings (2010)


Dave
69S

Fair enough...I just prefer the chisel to be very sharp, I haven't hit a journal yet. With that inner race warmed up it only take a little "tap" to get the race to move away from the cheek. Then again I haven't had to use this method in many years as a puller is readily available for $40 brand new.

http://www.harborfreight.com/automotive ... 30305.html

This will pull the inner races off with ease. It takes longer to pull it out of the box that is does to actually pull the races.
 
Gents,
We are talking about the crankshaft for goodness sake. Get the correct bearing separator, and try never to tell anyone you took a chisel to a crank bearing journal! The correct puller should cost about $30-50. A replacement for your crank is a bit more. Journal repair also not too cheap.
 
Builder,
Yes, I didn't hit the journal, just chewed up the cheek a bit on the outside edge.

Twinshocker,
According to Mick's DVD he just bolted them back together, make sure you use new nuts and bolts on the crank and on the con-rod bolts and nuts too. Side play depends if you are using 2 roller bearings or 1 roller bearing and 1 ball bearing (timing side). Side play is not adjusted with 1 ball bearing in the timing side, with both roller bearings, I have seen everything from .005 to .02". I am going for between .005-.010 on mine http://www.oldbritts.com/11_067569.html and http://www.nortonownersclub.org/support ... e-releases. Norvil has a real good price on the bottom end rebuild kit if you need the nuts and bolts.

Dave
69S
 
It always pay to pay that extra for a decent puller, small investment even if only used once but while you have your Norton its good to have every tools that is needed for it and all my bikes.

Ashley
 
Agree but its finding them
It always pay to pay that extra for a decent puller, small investment even if only used once but while you have your Norton its good to have every tools that is needed for it and all my bikes.

Ashley
Bought mine from a dealer clearout about 40years ago... looks of US manufacture.. good kit.. but given Freddie's location would try Norman White or maybe Russels of Falconroad London both ofwhomwill have the necessary kit
 
Crank half in a bowl of ice water. Mapp gas torch heating the bearing journal. Two utility knife blades - one each side of the bearing with the knife edge at the interface of the journal and crank. Light taps on the utility blades with an aluminum drift - be sure to alternate between sides.

The ice water could just be water as the point is to protect the crank from excessive heat. The journal usually comes right off. Sometimes, the blades just get it to come up enough to get a puller on it or to use something thicker to lift them.
 
Use a mini angle grinder (very carefully!) to grind about half way through then split with a chisel,
Dave.

This one from back in 2010 for me but you need to be very careful, no chisels though.
Then this with the inner heated with a heat gun.
Makes life easy for the journal and the oil seal area that it part and parcel of it.
Same going back on with a weight on the heated inner so it can not creep as it cools.

Main bearings (2010)


This was the flywheel out of my Sunbeam that mounts on a large taper, hard enough that the usual lathe tip tools would not work.
That was one of many bruises on it, just shows what determination can produce.

Main bearings (2010)
 
Mick in his DVD says you can beat it off with a chisel if you are real careful.

I find it hard to believe Mick Hemming's would suggest such a Bogan method.
If the inner race is going to be removed in that dodgy manner at least use fox wedges not a chisel which has an tip angle for cutting not wedging. :eek:
Coming to you from a Boilermaker.

A fox wedge.

Main bearings (2010)
 
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