Hidden bolts

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MickeyMoto
Posts: 2415
Joined: 22 Nov 2008 17:41
Location: Even further oop North

Hidden bolts

Post by MickeyMoto »

I found the source of my oil leak, it was a loose crankcase bolt, the one above the alternator.

Looking in the blue book, it shows an Allen head on the internal side, the same as the external bolts. On mine, it has a hex nut shape in the crankcase on the internal side. Was there a change, as I may have placed the copper washer incorrectly. I presume the washer goes on the internal, nut side?

Thanks,

Mike.
3potjohn
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Joined: 02 Jun 2007 13:58
Location: Devon

Re: Hidden bolts

Post by 3potjohn »

I think my K has hex headed hidden bolts. Have only seen them twice in ten years, which sounds like the punchline of a joke.
I too got a leak from them first time, probably bodged by a wipe of threebond.
John
MickeyMoto
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Re: Hidden bolts

Post by MickeyMoto »

Thanks, John. I'll have to see if there is enough room in the other side for a socket for a nut...
EVguru
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Re: Hidden bolts

Post by EVguru »

The socket head goes on the "wet" side with a copper washer under it and the nut goes in a hexagonal recess on the "dry" side.

Late engines use a rubber seal between the case halves (same seal as the oil pump feed) for the uppermost internal bolt.


cases.jpg
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Paul Compton
http://www.morini-mania.co.uk
http://www.youtube.com/user/EVguru
MickeyMoto
Posts: 2415
Joined: 22 Nov 2008 17:41
Location: Even further oop North

Re: Hidden bolts

Post by MickeyMoto »

Ok, thanks. That is the conclusion I have come to. I assembled it incorrectly. I did add the rubber, but was confused by the hex in the wet side. Not a big deal as it takes 45 minutes to disassemble the clutch side. Just waiting for the parts to arrive and put it back together.

The fears of a knackered plain main bearing have gone. I thought it was the main bearing oil seal. The oil came out with no metal in it.
EVguru
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Re: Hidden bolts

Post by EVguru »

OK, I had to go and check and it appears Morini may indeed have changed their mind about which way the bolts go through.

One of the dry side recesses on the 500 Sei cases in my picture has a hex recess, but the other one doesn't. The clear hex recesses are on the wet side.

The drawings on the parts microfiche differ. Early ones show the bolt heads on the wet side, but later ones on the dry side.

They may have changed it just for ease of assembly. I can recall having problems getting the nut to sit in the hex recess.

In any orientation, I'd have the copper washer under the head of the bolt.

case 500.PNG
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case 501.PNG
case 501.PNG (107.12 KiB) Viewed 4122 times
Paul Compton
http://www.morini-mania.co.uk
http://www.youtube.com/user/EVguru
stuartgurney
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Joined: 06 Nov 2020 14:41
Location: lyme regis

Re: Hidden bolts

Post by stuartgurney »

Not sure if this is in the right place - subject wise.
My dry clutch rattles when loose - normal I guess.
It's quite snatchy
I see ref to wet and dry clutches on the strada?
Can I just add oil to smooth it a bit.
Are there softer plates available?

Must be loads of info on the forum but hard to find!
Stuart
3potjohn
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Joined: 02 Jun 2007 13:58
Location: Devon

Re: Hidden bolts

Post by 3potjohn »

It is by design a dry clutch. These do rattle a bit. Wear on the slots and the corresponding tabs on the plates will contribute to this. Any burrs can be dressed out. Worth undoing the cover and stripping out, Likely some muck which will clean off with a squirt of brake cleaner. When tightening the clutch pack screws I find it best to tighten fully then turn back a quarter turn. I put a very fine rub of dry moly grease on those threads,
Useful videos by Paul Compton on the clutch exist if you search.
Any evidence of oil suggests a failing seal or oil getting past the clutch bush.
John
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Ming
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Re: Hidden bolts

Post by Ming »

stuartgurney wrote: 29 Jul 2021 07:06 Not sure if this is in the right place - subject wise...
...Must be loads of info on the forum but hard to find!
Stuart
Subject wise, no - but neither is this reply! To find info, try the following: your query site:morini-riders-club.com/forum
For your query, try clutch rattle, other queries such as engine oil, fork oil, spark plug, will turn up lots of previous posts.
MickeyMoto
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Joined: 22 Nov 2008 17:41
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Re: Hidden bolts

Post by MickeyMoto »

If a search is made against engine oil the Internet will slow up...
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