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  #1  
Old 2nd May 2021, 05:12 PM
Markiii Markiii is offline
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I'm really not sure if i should feel unlucky.............

or lucky that none of the things you've found so far killed anything
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  #2  
Old 2nd May 2021, 07:37 PM
MikkiJayne MikkiJayne is offline
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Quote:
Originally Posted by Markiii View Post
I'm really not sure if i should feel unlucky.............

or lucky that none of the things you've found so far killed anything
Every time I look at it, I find it astounding that the broken piece of starter didn't get jammed up in the flywheel and punch a hole through the gearbox casing.

I can't fathom how it happened in the first place, let along how it didn't take anything much larger out with it. Possibly it was dropped when the gearbox was changed, but based on the exhaust manifold bolts that must have been well over a decade ago. Possibly a crack started which very slowly propagated until the day it failed completely?

The water from the exhaust manifold is somewhat less lucky though.
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Old 2nd May 2021, 07:42 PM
Markiii Markiii is offline
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Is it possible something jammed up making it so hard to start that the starter pulled a huge amount of juice, thus frying the insulation and fracturing the starter motor?
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  #4  
Old 2nd May 2021, 07:58 PM
MikkiJayne MikkiJayne is offline
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You could stall the starter on the gear without putting a fracturing load on the casing though. Even if the bearing in the nose seized and stalled it, that wouldn't break the end off.

I think that day it wouldn't start was when the crack finally let go, the nose broke off, and it twisted the bearing such that the spindle couldn't turn. The stalled starter took enough current to fry the insulation, but when you let off the key it un-jammed itself. Possibly the broken piece fell off at that point and then it was able to start. The bearing does still turn now, although it is slightly distorted.

The starter came out without that piece attached at all - it was just sitting in the gearbox bellhousing, so it fell off through action of the starter at some point. Its pretty hard to tell where anything started though as its been bashed around by the flywheel.
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Old 2nd May 2021, 07:45 PM
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Adrian E Adrian E is offline
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Are you expecting bearing carnage when the cam covers come off, or does it appear to have been lubricating OK despite the emulsion in the sump?!
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  #6  
Old 2nd May 2021, 08:10 PM
MikkiJayne MikkiJayne is offline
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Are you expecting bearing carnage when the cam covers come off, or does it appear to have been lubricating OK despite the emulsion in the sump?!
Cautiously optimistic the bearings have survived as its only done a couple of hundred miles like this and it still turns over by hand just fine with no unpleasant noises.
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  #7  
Old 8th May 2021, 07:44 PM
MikkiJayne MikkiJayne is offline
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A slightly delayed update from Monday as I needed to talk to Mark about what I found before posting it, and then I was ill for the rest of the week

The engine has been steam cleaned on the inside! It turns out this mayonnaise is quite a good detergent.





The cam bearing journals are still perfect so no bearing damage



At this point I built a pressure testing rig which was derived from my radiator pressure tester. I hooked up a header tank and either looped or blocked off the various water pipes, vacuum filled it, and then pressurised it to 1 bar.

This was the result There is a crack in #7 exhaust port.



The water pools up in the port when the valves are shut, and drips out of the inlet manifold



When the valves open it pours in to the cylinder and sits on top of the piston



The water in the sump is from the water seeping past the piston rings



So, the left (bank 2) cylinder head is toast, and used heads are pretty much unobtanium. It might be possible to find the crack and weld it, but it would be contaminated with water and soot so welding would be extremely difficult, and not economically viable. Having discussed with Mark we decided the best way ahead is a replacement engine.
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  #8  
Old 8th May 2021, 08:16 PM
MikkiJayne MikkiJayne is offline
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Having made a shopping list and ordered a bunch of parts, I wanted a better look at the broken engine to see if it is saveable, should a head turn up in the future. Also, we wanted to see if the cam chain tensioners were still good, as I know the ones on the replacement engine are not.

Bank 2 tensioner removed - this crud in the oilway is what destroys the filter gauze which then kills the tensioner. I've never seen this much before though. I think this is gunge from the mayonnaise detergent effect cleaning everything out



Amazingly the gauze has survived!



Alas the bank 1 gauze and consequently tensioner has not survived. No idea why its always bank 1 that goes first.



The start pin still locks, but the non-return valve doesn't close fully so this will make a very brief rattle on startup, but not frightening clatter that the start pin causes.



The creamy slime drips out of every oil way



Well, you can tell which cylinder was ingesting water Its spotless!



The head has been cleaned too



The cylinder wall is perfect though - I feared the water may have washed any lubrication off the bore and caused it to be scored by the rings but it has survived, meaning the engine is definitely saveable in the future



A slight stain on the cylinder wall from where the water has been dripping in, but there's no damage to the surface. Its just discolouration.



#8



#6



I started stripping the engine to clean it up. I want to get as much of the emulsion out as possible before storing it so it doesn't end up separating and leaving the engine full of moisture.



Not too bad under the valley cover



The oil retention valves are pretty nasty though. I don't want to retain any of this!



The upper sump is pretty dirty too - all the usual carbon deposits have been loosened up



Very clean in the block though - all the carbon deposits have been washed off in to the sump. Just lots of the emulsion hanging about.





Cleaned with carb cleaner. Once I've got as much slime out as I can I will spray the inside with oil to keep it clean until I find a head for it.



I tipped the engine on its side with the remaining head down, with the cams removed, so the gunge can drip out under gravity overnight.



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  #9  
Old 8th May 2021, 09:43 PM
Markiii Markiii is offline
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looks surprisingly good in there all things considered.

makes me wonder if a steam clean isn't a good idea
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  #10  
Old 8th May 2021, 09:51 PM
spannerrash spannerrash is offline
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These heads of no use?

https://www.ebay.co.uk/itm/GENUINE-A....m46890.l49286
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