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#45
by
Mark(The Miser)UK
on 01 Mar, 2012 20:12
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I always thought that the cross hatch pattern was to facilitate a "honing" between the rings and cylinder wall so that there would be a match of surfaces. 30* for street engines and 45* for race. The theory was 45* will wear in faster and seat more quickly. Unfortunately, it will also wear out faster hence the 30* for street engines. Every oil holding scratch is a potential compression leak. Oil holding capabilities are enhanced by knurling the piston skirts which will not wear as much as the friction between it and the wall is less than the ring & wall.
Not heard the skirt knurling idea before. I don't think it is correct though because even with my rings stuck in flush [remember 7 out of 12], and they were able to do this because their radial thickness had reduced by 2 or 3 mm IIRC, only one skirt had any bore marking at all, other than it's original machining, so it doesn't touch.
That is not to say that it isn't floating in a film of oil though.
I used to have trouble grasping why a glazed bore isn't the optimum, after all a polished ring on a polished bore has to be the closest fit. It probably is in the end, but as I understand it, the deglazing allows ring to form the correct shape during the short break-in period. The remaining fine traces of the knurling aid to trap small amounts of oil that won't burn away but give and a degree of lubrication to the rings.
A big question is perhaps how many knurls per inch of travel are sufficient for long bore life. I assume their depth has to be just sufficient to hold the oil, as too deep and as you point out they could get flushed by passing combustion gasses...
What resistance to flow does a short length of hair sized 'tube' have, and how much more does it's resistance increase when say halved?
With the bottle method, I wouldn't say that the remaining knurling was very deep. It is certainly working well at the moment, but for how long I don't know. It's been about 18 months. Now I can actually change the oil rather than keep topping it up.
The black grease that used to be on the splash cover is not appearing anymore, so whatever I did seems to be an improvement fuel economy wise and with the engine condition...I don't race it other than going up to 85 or so I'm not sure of the benefits of knurl angle. I suspect that too many knurls spoil the broth 
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#46
by
clbanman
on 07 Mar, 2012 09:37
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Just received an original copy of Mechanics for Young America, a 1910 Popular Mechanics compilation. No other copy to be found other than print to order. Windmills, early cars, paper covered canoes. and the earliest wind surfers I've ever seen...[/color]
It's available online at The Library of Congress
http://www.archive.org/details/mechanicsforyoun00chic.
Nothing wrong with trying new things in my opinion. Based on what you paid for your car, I consider your approach to be sensible. As far as the "correct" way to do things, yes technically they are right. However, I regularly deal with suppliers that have better equipment than I have available for both manufacturing and measurement, and yet cannot meet the proper dimensional specifications. As previously mentioned, good equipment is not a substitute for truly understanding what the requirement of an assembly is. I've seen old school tool makers who can hand file a dovetail to mate two metal parts that very few machinists could duplicate.
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#47
by
theman53
on 07 Mar, 2012 13:35
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Right.
I guess what I and some others have been trying to get across is this...Cheaper is not nessesarily better. I can't tell for sure as I didn't see it in person, but the pics I saw here looked bad. I never got a block back from a machinist looking like that, and if I did I would probably question taking something back to him.
I don't care what someone does to their own stuff, but if I am going to publish something I did on the web *as I have stated before* I would put a disclaimer on it.
For me it comes down to doing something better, not cheaper. Sometimes it costs more, sometimes less, but I strive to do the best I can, not the cheapest I can...sometimes they can be the same.
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#48
by
belchfire
on 07 Mar, 2012 13:50
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Amen to that.
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#49
by
Mark(The Miser)UK
on 08 Mar, 2012 02:17
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Right.
I guess what I and some others have been trying to get across is this...Cheaper is not nessesarily better. I can't tell for sure as I didn't see it in person, but the pics I saw here looked bad. I never got a block back from a machinist looking like that, and if I did I would probably question taking something back to him.
I don't care what someone does to their own stuff, but if I am going to publish something I did on the web *as I have stated before* I would put a disclaimer on it.
For me it comes down to doing something better, not cheaper. Sometimes it costs more, sometimes less, but I strive to do the best I can, not the cheapest I can...sometimes they can be the same.
Sorry I don't quite get your point. Looking like what? You mean the bores or the environs? Clearly the deglazing of the bores worked, and sending the engine to the machinists, doesn't usually mean sending the complete dirty car with it.
I don't have the view that cheaper is better. I have the view that paying through the nose to all those trying to make a 'crust' or indeed a complete 'loaf' out of my pocket is not neccessarily better. Unless sending engines to one-man-bands, mundane work often gets handed to understudy, apprentice, or novice, coupled with a time constraint...
This forum is littered with apparent failures by 3rd party 'experts'
I do not recommend that everyone does this, but if they doit is merely a harmless ad/venture. This is merely a demonstration of what can be achieved, with almost nothing. I know it worked, is working for me.
If some wish to only follow the Bentley which is a copy of VAG, which said in the era of plenty heads, do not reskim heads, although they changed their mind after production stopped, then so be it. More fool you/them. Is this forum to only promote VW policy.
What harm could it have done?
What harm has it done?
I would like people including you to answer those points.
I'll be first on the list. After 18months...No harm could be done other than a little time waste if unsuccessful. No harm has been done.
This has been a total success and so must be a professional job [I have to say that due to the lack of humour on your side of the pond] This great job[free] was done on the 12th August 2010. On 17th June 2011 the car complete with this engine went through it's annual MOT here in the UK. The official pass limit smoke test for a car of this era is 3% [modern TDI's 1.5%] This car didn't need the best of 5 attempts but passed on the Fast Track for under 1.5%, with a score of 1.1% .
Need I say any thing else?
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#50
by
theman53
on 08 Mar, 2012 05:07
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I have explained earlier that the harm done could have been:
Junk in the engine/crank
Poor ring seal=you are still using oil, more than any VW engine I have ran.
All the parts ex: HG, bolts, antifreeze, oil, and TIME that you could have possibly had to do over.
You could have scratched the walls to a point that it needed bored, thus causing more $ to be spent.
What harm has it done? I don't know, other than this thread.
I have also stated earlier that I have personally done some things not in the Bentley. I do however think that it should at least be consulted if you are thinking of doing a practice that is non standard, IF you don't know exactly what you are doing. Most days I do not need my Bentley as most of it is in my head. I mainly use it for electrical and interior work, but for someone who doesn't know it or what the jist is they should have it open IMHO.
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#51
by
Mark(The Miser)UK
on 08 Mar, 2012 06:04
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I have explained earlier that the harm done could have been:
Junk in the engine/crank
Poor ring seal=you are still using oil, more than any VW engine I have ran.
All the parts ex: HG, bolts, antifreeze, oil, and TIME that you could have possibly had to do over.
You could have scratched the walls to a point that it needed bored, thus causing more $ to be spent.
What harm has it done? I don't know, other than this thread.
I have also stated earlier that I have personally done some things not in the Bentley. I do however think that it should at least be consulted if you are thinking of doing a practice that is non standard, IF you don't know exactly what you are doing. Most days I do not need my Bentley as most of it is in my head. I mainly use it for electrical and interior work, but for someone who doesn't know it or what the jist is they should have it open IMHO.
Oh dear truth out then. You just don't like innovation.
It is good that all your engines are better than book for oil burning, but then a rebore will give you a new engine.
Perhaps you can write a correct thread of how you do it, then those who have recently or historically filled this forum with tales of rerings and attempts to follow the book, or even sent it to an'expert' can see where they have gone wrong and are still burning oil.
As I said I have oil leaks from the brand new bushing on top of the cam cover, but doesnt seem to be burning anything.
What junk into the engine? Please remember I did take the sump off and the pistons out, and can you see the rag draped on the crank? I can't, yet it was there. 
Anti freeze? Don't you collect yours? Cheaper than heatshields now so even I renew.
Deep scratches? I think you are in error there. I think you will find the bores quite hard and resistant, and, unlike a honing stone at a relatively high speed, the paper was air cushioned. I thought you were going to say it weasn't knurled enough for your liking. So rest relieved the scratches are minimal. Having given you the smoke results they must be sufficiently small.
I went to the great expense of importing a Bentley from America for the Quantum. Was it worth it? Alas nope.
Good gearbox stuff, but unfortunately [fortunately] they rarely go wrong on a Quantum, unless totally abused.
Poor descriptions generally and an obsession with merely showing proprietary tool for rempoving seals that can only be used on the Quantum or Audi 4000 etc and only hanging on a dealerhip wall.
At least the Haynes was based on someone stripping the car down and rebuilding, or at least the mk2 and earlir stuff back into the 60's and 70's Mk3 manuals had the worst elec diagrams around, and it seems all mauals that followed went the same way.
If you write a thread it will be good for balance, and I'm sure without the damnation that follows mine.
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#52
by
srgtlord
on 08 Mar, 2012 06:09
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A job well done! I have heard of people using a sponge to wipe off rust in an engine, and people who slap rings in an engine without reboring, but not sandpaper. If it works then props to you sir! The proper way is not always the most cost effective way. For instance rusted out rear shock tower, spare sheet metal, rivets, arc welded suppport bracket, and bondo = drivable car
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#53
by
belchfire
on 08 Mar, 2012 10:07
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As Bugs Bunny once said, " No sense arguing with a genius". I think I'll quit this thread. British humor? Yeah, that Benny Hill sure was a knee slapper alright.
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#54
by
smutts
on 08 Mar, 2012 14:24
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This forum is littered with apparent failures by 3rd party 'experts'
So It wasn't just me that noticed this?
Unfortunately more should take the doctors pledge of "Do no harm" to heart.
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#55
by
theman53
on 08 Mar, 2012 15:14
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I think you are arguing just to argue now. I left out besides scratching the cylinder too deep, from uneven pressure and coated abrasives being what they are, you could have left them not roughed up enough or in a pattern that didn't work with the rings.
The end to my story is this: which one would you rather have in your car if both cost the same?
OR
If you feel ok with it in your car fine. I nor anyone else that has a different opinion than you on the bottle isn't attacking you and trying to convert you to proper hone only. I and others are just trying to show that there is a different option to what you see as a different option. I am removing comments that are not in line with the thread.
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#56
by
truckoSaurus08
on 08 Mar, 2012 16:36
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Wow the man is really being "the man" about this.
I think marks methods are not for everyone but at least he offers an alternate way of doing things for those willing to take the risk.
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#57
by
Mark(The Miser)UK
on 08 Mar, 2012 17:04
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I think you are arguing just to argue now. I left out besides scratching the cylinder too deep, from uneven pressure and coated abrasives being what they are, you could have left them not roughed up enough or in a pattern that didn't work with the rings.
The end to my story is this: which one would you rather have in your car if both cost the same?
OR
If you feel ok with it in your car fine. I nor anyone else that has a different opinion than you on the bottle isn't attacking you and trying to convert you to proper hone only. I and others are just trying to show that there is a different option to what you see as a different option. I am removing comments that are not in line with the thread.
Well your example is a tidy, good example of a deep hone, although what are those vertical scratches? A reflection of something or actual remnants of a damaged bore.
It certainly looks better than mine, as I felt I had been too lenient. If the costs are the same then there is no incentive to use a bottle, unless nothing else is available.
My method does appear to have worked, but who knows perhaps my experiment will only last a few more years, whilst yours might last longer. Only time can tell.
I am only showing what I have done to my engine in my car. Judging by those ring gaps on an earlier picture, this engine had done a lot of mileage prior to the rering It is a little noisy, but as it is still getting 45 to 60mpg imp and it's reliability is why I don't take the GTD engine out, which is quiet like a mouse.
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#58
by
Blocksmith
on 09 Mar, 2012 17:58
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My method does appear to have worked, but who knows perhaps my experiment will only last a few more years, whilst yours might last longer. [/color]
I think that's the core of the debate right there. Whether or not to experiment, or when experimentation is justified.
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#59
by
ORCoaster
on 09 Mar, 2012 18:54
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Experimentation is justified when several conditions exist; not all have to hold true on only will do.
1. You have nothing to lose by trying. This is applied when the part is already broken and what ever you do will likely fix it.
2. You are pinched for either time of more often money. If you can't "run out and get the right tool or part" then experimentation is warranted.
3. You have a backup. If you can go to another spare part that is still in serviceable condition if the experiment blows up in your face.
There may be others as well but I move on.