the.cern
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« Reply #345 on: 14 May, 2015, 06:05:19 PM » |
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That's an encouraging sight!!!
Have you a photo of the extra M8 bolt at the rear you had to remove? What is it for or attach to?
Here is the best photograph I have of the bolt. It is so close to the rear end of the sump that you can see it in this end on view!!! I know not what the heck it is for!! It bolts into the centre of the rear main bearing cap. Andy |
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the.cern
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« Reply #346 on: 14 May, 2015, 06:26:06 PM » |
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Today I gave the studs (and myself) a rest and decided to tackle the big ends and mains. The main reason of course is that I do not want to do any more on the studs until I have the tools from David and Colin. The good news is that they arrived today. The bad news is that I now have no excuses (apart from the usual laziness) and must try to get the last little beggars out tomorrow. I agree totally that the eccentric load on the stud using Davids tool is an issue. However, this problem does virtually disappear if the tool is positioned at the base of the stud and, more importantly, if the turning load can be applied at the level of the gripping knurled wheel. As the tool requires the use of a socket set 1/2 inch drive this is not possible, but one should avoid the use of an extension piece. More to follow.
Andy
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DavidLaver
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« Reply #347 on: 14 May, 2015, 07:34:49 PM » |
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Feel free to get a pipe wrench on the outside of the tool to apply the load low. I'm not at all worried about the plating being damaged or any other marking on it. Its MUCH more important that it improves your chances as best as it can. Battle scars will be carried with pride.
Also you are more than welcome to modify it, perhaps drill a hole (or two) in it to take a bar? Maybe grind flats on for a really big spanner or to grip it better?
Also don't be so hard on yourself that the studs are the priority. It all needs doing, there's no critical path, any progress is progress, its a hobby and supposed to be fun etc etc.
David
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David Laver, Lewisham.
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DavidLaver
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« Reply #348 on: 14 May, 2015, 07:37:07 PM » |
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I just remembered the other way to shift a stud - weld or braze a nut near the base... It assumes you're going to throw it away after which I think would have to be the case after using a toothed extractor on it.
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David Laver, Lewisham.
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chriswgawne
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« Reply #349 on: 14 May, 2015, 08:25:43 PM » |
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Colin,
Your Koken extractor is a quality tool. Necessary for this application I would say and better than Draper etc. Where in the UK are they available?
Chris
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Chris Gawne
Mobile: 07778 216552
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the.cern
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« Reply #350 on: 14 May, 2015, 09:22:19 PM » |
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David, thank you for the carte blanche to trash your tool, I will do my best ...... not to!!! Seriously, I am looking forward to tomorrow and to seeing how the tools perform. It promises to be an interesting day!!
Not that today was not interesting!!! I am trying to get my head around the cylinder numbering system. I am aware that things are not consistent and have been using my own unique system that, so far as I am aware, does not accord with any accepted system. I simply number the cylinders in each bank 1 to 3 with 1 being at the front and designating the bank, either left or right.
Today I inverted the engine and started on the big ends and the mains. The mains are numbered 1 to 4, with 1 being at the front. However, the big ends are numbered 1 to 6 with 1 being at the rear of the engine. At present I am marking the big ends using my system, for the mains I am using the marked system.
All the caps to the mains are off, a moment of panic as a spacer (shoulder according to TAV 4, item No. 17) from one of the main bearings dropped into the block. I managed to retrieve that, but then realised there should be two, one each side of the bearing!!! After a frantic few moments I located the other one, stuck to the side of the bearing cap!!!!
Now the big ends!!! The nuts to the big end caps for cylinders 2 and 3, both left and right (my nomenclature) were all readily accessible and easily undone and the caps removed, numbered and stored safely.
Then time to look carefully at the journals. I felt they were not at all bad, until I looked at No.4 main!!! See photograph!!! Quite how bad this is I am not sure, I just do not have the experience. That is one for an expert. Also, I have not yet been able to measure the journals .... I must hope that they have not previously been machined down to their limits!!!!
In addition I carefully marked the crank and camshaft sprockets before I removed the timing chain. It should help with re-assembly, but will need careful checking.
Let us see what tomorrow brings !!!
Andy
Photographs ... crank and camshaft marking. Rear main bearing journal scoring
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the.cern
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« Reply #351 on: 14 May, 2015, 09:33:03 PM » |
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I just remembered the other way to shift a stud - weld or braze a nut near the base... It assumes you're going to throw it away after which I think would have to be the case after using a toothed extractor on it.
This is apparently one of the standard solutions to the problem.... It addresses two issues, firstly it provides something on the stud on which a spanner (or similar) can get purchase. Secondly it provides heat to the stud/casting interface which will always help in freeing the stud. I am hoping that I will not need to pursue this option!!! Andy |
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DavidLaver
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« Reply #352 on: 15 May, 2015, 07:49:49 AM » |
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In the last photo with the scoring, is it just confined to that central stripe?
If the side sections are fine that's a very generous bearing area and my instinct is that it wouldn't matter a jot.
At BWE one day we put a 1600HF Fulvia engine next to an Aprilia engine and the Aprilia had perhaps twice the bearing surface. It really doesn't need it all... My memory isn't good so I may have overstated it. The crank case also was much more chunky. I wonder how the bearing area and crankcase would compare to a modern bike engine of the same power?
David
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David Laver, Lewisham.
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DavidLaver
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« Reply #353 on: 15 May, 2015, 07:51:17 AM » |
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Of course you don't know until you measure it but so far that looks like very good news with the crank.
David
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David Laver, Lewisham.
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DavidLaver
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« Reply #354 on: 15 May, 2015, 07:58:21 AM » |
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Just because its such a beautiful thing any chance of some photos of the sump inside and out? By way of contrast the extent a pressed tin sump has to be modified to come close: http://www.ralloy.com/images/RAL057xLarge.jpg |
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David Laver, Lewisham.
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the.cern
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« Reply #355 on: 15 May, 2015, 02:02:34 PM » |
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In the last photo with the scoring, is it just confined to that central stripe?
If the side sections are fine that's a very generous bearing area and my instinct is that it wouldn't matter a jot.
At BWE one day we put a 1600HF Fulvia engine next to an Aprilia engine and the Aprilia had perhaps twice the bearing surface. It really doesn't need it all... My memory isn't good so I may have overstated it. The crank case also was much more chunky. I wonder how the bearing area and crankcase would compare to a modern bike engine of the same power?
David
David, reference the scoring in the main journal. It appears to be merely that central stripe. I agree with you that there should be more than adequate bearing area ignoring that. The other journals that I have inspected seem good, maybe some ridging, whether or not it is significant I really do not know. I will have to have them checked. Also I must measure the journals, hopefully there is enough meat on them to allow for any necessary work!!! Now, stud removal tools, both did the job excellently. If I had realised how good they were I would have bought something without going down the two nut route. David's (Draper) tool was more cumbersome and suffered with the disadvantage of the eccentric loading but fitted in amongt the studs and performed well. The Koken looks and feels a better tool, but I am sure is more expensive, especially if you are working with different sized studs as the tool is suitable for one size only, The Draper would operate on studs from 3mm to 24mm (my assessment of the range, not official figures). In my opinion the Draper would be suitable for the occasional user, whilst the Koken would be worth the extra cost for someone who frequently finds themselves attacking studs. The two nut method is best left for emergencies only!! My present situation, the score is ..... Sheared by others 1 Sheared by me 5 Successfully removed 26 Not too bad. I will get the stud stubs removed by the machine shop when all the other work is done. The biggest surprise was the badly corroded stud, the Draper removed it easily. The Draper is almost always set at the base of the stud, in this case well below the corroded section. I am sure the Koken would have done an equally good job, but would have required the top of the stud to be cut off to allow the tool to grip at the base of the stud. If I had used the two nut method I would have just sheared the stud in the corroded area. Photographs ... Koken in use, Draper in use, block without all those sticky out bits!!!! The red and yellow lines around the block in the last photograph are to secure the crankshaft in place. All the main bearing caps have been removed plus the big end caps for the four rearmost cylinders. Theoretically the crankshaft is held in place only by the big end caps of the two front cylinder and could move. This would induce a bending moment in the con rods, not advisable!!! Jim says I am overcautious!!! Andy |
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ColinMarr
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« Reply #356 on: 15 May, 2015, 07:41:49 PM » |
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Good result – well done!
Just one comment: The concentric Koken tool is designed to fit over the stud and go right down snug close to the block, with actuation then by either a tubular box spanner working on the flats, or an open ended spanner rather than a socket.
I think the journals look OK, subject to measuring up.
Colin
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the.cern
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« Reply #357 on: 15 May, 2015, 09:56:13 PM » |
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Thank you Colin, I thought it was excellent even though I did not know how to use it. Hopefully I will not ever need to tackle these again, but if I do then I will do it properly!!!
Andy
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DavidLaver
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« Reply #358 on: 15 May, 2015, 10:39:02 PM » |
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Well done indeed... As for ties round the crank can you be too careful?
Was the Koken more gentle on the studs? Does it bite or crush?
David
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David Laver, Lewisham.
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the.cern
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« Reply #359 on: 15 May, 2015, 10:54:34 PM » |
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I think bite rather than crush. It was certainly very effective, The fact that today I managed to shear 4 studs today is not a reflection on either the Draper or Koken tools Rather that all the studs I tackled today, with the exception of the badly corroded one, were the most seized, having previously resisted the two nut method!!!
Tomorrow is get the crankshaft off and tackle those seized pistons. Jim will be round to play, so definitely there will be a lot of abuse and hopefully there will be a lot of progress!!!
Andy
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