Separating crankcases

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Daddy Dom
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Re: Separating crankcases

Post by Daddy Dom »

I thought I'd strayed onto the Laverda forum for a minute! :P
MRC 3082½
70sbikes
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Location: Melbourne Australia

Re: Separating crankcases

Post by 70sbikes »

A guy from NSW Australia posted a question on Facebook about removing the cam belt pulley from his 1976 3 1/2 Sport. The picture he posted shows the exact same case as mine! Looks like a few transitional bikes were sent to Australia. I gave him the correct answer (and threw some more business Ralph Restorations way).
MickeyMoto
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Re: Separating crankcases

Post by MickeyMoto »

Al B wrote: 29 Sep 2021 09:12 In a Joyce Grenfell style...

Now now children, this is a family forum
Yes, you are quite right. Apologies, I have amended the post so that it does not offend. Sorry it took so long, been away driving on motorways to deliver some herbal substances. Just waiting for the speeding and undue care and attention tickets.

Don't want the forum descending into the gutter.
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Daddy Dom
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Re: Separating crankcases

Post by Daddy Dom »

70sbikes wrote: 02 Oct 2021 12:23 A guy from NSW Australia posted a question on Facebook about removing the cam belt pulley from his 1976 3 1/2 Sport. The picture he posted shows the exact same case as mine! Looks like a few transitional bikes were sent to Australia. I gave him the correct answer (and threw some more business Ralph Restorations way).
If it's not too late, you can always change your belt the easy way:
*cut the belt in half lengthwise, creating two thin cambelts.
*remove the outer strip, then fit the new belt half on.
*cut the inner strip off and push new belt home fully.
*have a beer.
MRC 3082½
70sbikes
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Location: Melbourne Australia

Re: Separating crankcases

Post by 70sbikes »

Success!!

The stainless M6 threaded rod arrived. I looked at it, and wasn't happy with its structural strength. I had a "Eureka!" moment when lying in bed late at night - what I needed was some stainless tube with an ID of just over 6mm. eBay soon had that sorted. It arrived, and I set about cutting the bits to size:

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I then secured these to the engine case:

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Then I flipped the motor and attached the tool:

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Following the sage advice on this forum, I got the case nice and hot with my trusty heat gun. It took a fair bit of pressure before the case finally came away from the bearing. It was a matter of heat, turn the tool, pry, smack the protruding bits, repeat. When the bearing released I actually sang the "Hallelujah Chorus"!

Image

The great thing about being retired is I can take my sweet time on this project. I think I'll have a bit of a rest before taking the next step...
70sbikes
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Location: Melbourne Australia

Re: Separating crankcases

Post by 70sbikes »

I went out to the garage and looked at the bearing. I then looked at a two jaw bearing puller, ground it so it would fit, and whipped off the bearing!

Question about my crank. It only has one grub screw on one side for the sludge trap. Normal?
EVguru
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Re: Separating crankcases

Post by EVguru »

As previously stated, the bearing should have been a slip fit on the crank. Make sure that's the case with a replacement bearing. Have the crankshaft sleeve polished to correct tolerance if required.

There are two oil gallery screws on ball race cranks. One on the face of the timing side crank web, to cap the crankpin drilling and a smaller one on top of the oposite crank web that caps the drilling from the crankpin gallery down to the mainshaft feed.
Paul Compton
http://www.morini-mania.co.uk
http://www.youtube.com/user/EVguru
70sbikes
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Re: Separating crankcases

Post by 70sbikes »

It definitely wasn't a "slip fit"! I'll make sure the new bearing is though.
70sbikes
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Re: Separating crankcases

Post by 70sbikes »

I measured the sleeve and the bearing. Sleeve is approximately 29.97 mm OD, bearing is approximately 29.90 mm ID. So, I have a difference of 0.07 mm. I checked a brand new SKF bearing, and it also measures 29.90 mm ID. What size should the sleeve be for an ideal fit?
70sbikes
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Re: Separating crankcases

Post by 70sbikes »

Today I tackled another job I'd been dreading - a seized sump plug. After watching Paul Compton's YouTube video, I bought a step drill. Success! I reckon at the exact same moment as in Paul's video the plug tightened, after which it came out very easily. The man's a genius!

Image
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P&S
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Location: Roma

Re: Separating crankcases

Post by P&S »

Hello 70sbikes,
could you please post the link to the video?
For the future better try these from Ducati Monster.
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70sbikes
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Re: Separating crankcases

Post by 70sbikes »

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P&S
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Location: Roma

Re: Separating crankcases

Post by P&S »

Thanks!
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