Main Bearing Removal

I am trying to remove the main bearings from the crank cheeks. In the Mick Hemmings video, he removes the ID Race with a specialized tool which he reiterates of it being quite rare and expensive. The issue with mine is that the roller bearing (center piece) part of the bearing did not come off with the crank casing like in Mick's case. In fact, on my timing side (If my memory does not fail me) the whole bearing stayed with the shaft. I tried to heat one in a kitchen oven but it did not come off... I started to second guess my thermal expansion theories and wondered if I should have even bothered heating the sucker up... I also removed the cheek from the oven and gently used pry bars to try to remove the bearing, with no avail of course.
Do I need this bearing removal tool? Or is there alternatives?

If you want to reuse the bearings, you will need a bearing puller, which are not expensive and easily available. If you intend to fit new bearings, simply remove the outer bearing races, and cut almost completely though the inner race with an angle grinder, and spilt with a cold chisel.

CDubb said:

I am trying to remove the main bearings from the crank cheeks. In the Mick Hemmings video, he removes the ID Race with a specialized tool which he reiterates of it being quite rare and expensive. The issue with mine is that the roller bearing (center piece) part of the bearing did not come off with the crank casing like in Mick's case.

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It sounds like it's the older 'NF306, or MRJA30, (or 6/MRJA30) roller bearing. Both NF and NJ (NJ = rollers captive in the outer race and single-lipped inner) roller bearings were used on the early Commando engines apparently.

In John Hudson's NOC engine rebuild video he demonstrates removal of that type of bearing by levering the individual rollers out of the cage which then allows him to remove the cage leaving only the inner race which he extracts with a bearing puller after heating the race with a blowtorch because it was tight on the shaft.

CDubb said:

In fact, on my timing side (If my memory does not fail me) the whole bearing stayed with the shaft. I tried to heat one in a kitchen oven but it did not come off...

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Is that a ball (rather than a roller) bearing?

According to my old workshop manual:

"Removing the roller bearing
Use a stout pair of pliers to grip each side of the roller, when a sharp upward jerk of the pliers will extract the roller."

And

"The inner member can be removed with the use of two sharp edge wedges placed each side of the steel sleeve and crankshaft which will move the bearing member sufficiently far enough to enable a regular claw-type extractor to be used for final removal."

Dave
69S

Carbonfibre said:

If you want to reuse the bearings, you will need a bearing puller, which are not expensive and easily available. If you intend to fit new bearings, simply remove the outer bearing races, and cut almost completely though the inner race with an angle grinder, and spilt with a cold chisel.

Click to expand...

I will be replacing the orginal bearings with the FAG Superblends.

DogT said:

According to my old workshop manual:

"Removing the roller bearing
Use a stout pair of pliers to grip each side of the roller, when a sharp upward jerk of the pliers will extract the roller."

And

"The inner member can be removed with the use of two sharp edge wedges placed each side of the steel sleeve and crankshaft which will move the bearing member sufficiently far enough to enable a regular claw-type extractor to be used for final removal."

Dave
69S

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This means no heat necessary? I am not sure what you mean by Stout? or even what type of pliers you are mentioning? if the plier handle is inline with the pulling motion, how to you expect the pliers to maintain its grip with the rollers? Vise Grips?

CDubb said:

I am not sure what you mean by Stout?

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'Stout' simply means 'sturdy' and/or 'strong': http://www.thefreedictionary.com/stout

You may want to get a clam shell puller. Not expensive, Autozone will lend for free.
My inner was pressed up tight and it was just a matter of getting it away from the butt. Although caution is the word here, I used a sharp cement chisel with a 45 degree grind to separate it enough to get the tire levers in there then it came off with out issues.
NEVER let the chisel hit the crank journals.
WARNING! This may be bad advise, but we're not talking rocket science here, just common sense.
You may want to get a clam shell puller.

With the outer in the casing, set the case half across a couple of 2X4's. Concentrate the heat at the race with a heat gun. The outer will more than likely drop out. The trick is to localize the heat to where it is needed.

Carbonfibre comments on splitting it with an angle grinder. I have done this but used a cut-off wheel on my Dremel tool It is smaller diameter and easier to control than an angle grinder. Obviously you don't want to cut into the crank surface, but get close. The steel in the bearing race will be hard enough to crack when struck with the chisel in the cut you have made. This is pretty much my last resort for bearing removal but it does work. I would prefer to use it on the wheel bearings on a boat trailer or something than on the crank of my vintage bike. Be friggen careful!

Charles
Do you have a Princess Auto close to Saint John? They stock these bearing pullers. I sent you a PM.
Regards,
Thomas
CNN

Another way of removing a bearing race, if you have a MIG welding set, is to firstly remove the outer race, then weld a continuous bead of weld around the inner race, and then lever it off using 2 large screwdrivers, when the weld is still red hot.

and NO big Hammers , thanks . :?

I may be a little late but since I just did this job I thought I'd post some photos. 1st pic has 2 bearing splitters that are likely what was in the MH video. I think it is part #063970 in the Norton special tools but please confirm because my manual only has the pt # with no pic. I found the small one too small mainly because when you turn the nuts to tighten it down the width of the nuts from point to point is wider than the thickness of the tool and the corners hit the fly wheel cheeks. The big one however is so big the nuts are far off from the crank cheeks and it still fits. You squeeze in behind the bearing forcing it off the shaft till you get behind it and before you start clamping onto the shaft you use the perpendicular bolts to pull the whole thing towards the end of the crank. I would think the Norton tool is in between these 2 sizes.





Also in the 1st photo are some set up wedges and some chisels. I used to use set up wedges for this type of work before I had the splitters. Set up wedges are carbon steel usually and cost about $3-4.00 for the sizes shown. They are much thinner angled than the chisels you see opposite and ideal for this work. Set up wedges are sharpened like a broad axe with one side perfectly flat and the other side sharpened down on the end. Because of their very slight angle they are very useful for parting cases off the dowels and many other things too.

10 / 10 .

The thing to watch , particularly with the wedges or something improvised , is bottoming it against the mainshaft , and raiseing welts , bruises , and Stress Raisers / surface imperfections .
particularly on the radius from the face to the shaft . Any edges raised should be dressed flat / smooth before fitting bearings .

I've never heard of set up wedges Rennie but they look like they might be useful for all sorts of things. Any idea where they might be available from?

Looks to me like we need to go play at Rennie's house!

Mark F said:

I've never heard of set up wedges Rennie but they look like they might be useful for all sorts of things. Any idea where they might be available from?

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Any good welding hardware supplier should keep them (the thin wedges are known as 'Fox wedges' in the UK).

http://uk.farnell.com/roebuck/310390/fo ... dp/1552358

I've used that blue one to remove my original main roller. Just enough to bring the inner race off of the crank cheek ,then carefull use of a dremmel tool with small cutting wheel to eat away a slot in race. Weakened it enough to prise off easily.

I have them up to about 10" and it's surprising how often you use them. The main intended use is positioning very heavy equipment or machinery into position so it can be bolted together. Used by steel erectors, boiler makers, pipefitters, machinists etc etc. Any good tool store should have them. I googled and they're pricey at mcmaster carr's and grainger but sears showed up but then after 3 seconds it diverts to sears canada which doesn't have them. I saw a price of $7.95 for the instant the price was up. Everyone else seems really expensive. Stubborn me, I googled some more and look what I found:

http://www.rcttools.com/catalog/wedges/steel-wedges

rvich said:

Looks to me like we need to go play at Rennie's house!

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HA, I'm afraid you'd all get bored pretty quick around here.

I was thinking we should have a raffle to win a week at Jim's or Ken's or CNW. Then there's Ludwig and Weal Norton too but the airfare would cost. I have holidays coming up and was also thinking wouldn't it be great to spend 10 days or so with a bunch of us at cozmoz's garage since it would be big enough. We could all bring a cylinder head or a crank or something. It'd be kinda like the movie "City Slickers" where Billy Crystal and his buddies go to a working dude ranch for their holidays.