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francoangellini Samba Member
Joined: January 10, 2012 Posts: 223 Location: Chile-South America
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Posted: Sun Nov 27, 2022 8:00 am Post subject: Main bore steel job question |
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Hi;
My T3 case already has the main bore worn over 0.040", I plan to return it to std like this......Look the steel main bearing bore job photo.... Advantages and disadvantages''
My best
Last edited by francoangellini on Tue Nov 29, 2022 8:23 am; edited 8 times in total |
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Zundfolge1432 Samba Member
Joined: June 13, 2004 Posts: 12452
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Posted: Sun Nov 27, 2022 9:37 am Post subject: Re: Crankshaft bore question |
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I assume you are talking about what we would call shuffle pins? Keeps engine case halves from working against each other (fretting). This was more of a problem long ago using poor quality crankshaft and or being being way out of balance turning high RPM’s. Because it makes interference fit if you need to get back inside the engine you’ll be looking for a case splitter tool. So unless you were building a big engine, maybe turbo doing 1/4 mile passes you’d not need that. Some would say shuffle pins are a bandaid fix as a cover for using shitty parts just throwing parts together without balancing.
Or are you referring to steel backed main bearings? |
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jimmyhoffa Samba Member
Joined: February 16, 2014 Posts: 1046 Location: St. Louis
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Posted: Sun Nov 27, 2022 10:36 am Post subject: Re: Crankshaft bore question |
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Woah I don't think he's asking about shuffle pins! Look carefully at that case, it looks like it actually has a different material for the main, like someone hogged out the main and added half-shell bushings to sleeve it back down. My BMW was like that too, basically. It was a magnesium block and all the critical stuff was aluminum.
I would think if one were to do something like that, a strong alloy of aluminum like 6061-T6 or 7075-T651 aluminum would be the ticket. _________________ 1974 Chenowth 2RL #1244 Street Legal
My other car isn't ridiculous. |
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francoangellini Samba Member
Joined: January 10, 2012 Posts: 223 Location: Chile-South America
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Posted: Sun Nov 27, 2022 1:28 pm Post subject: Re: Crankshaft bore question |
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Zundfolge1432 wrote: |
I assume you are talking about what we would call shuffle pins? Keeps engine case halves from working against each other (fretting). This was more of a problem long ago using poor quality crankshaft and or being being way out of balance turning high RPM’s. Because it makes interference fit if you need to get back inside the engine you’ll be looking for a case splitter tool. So unless you were building a big engine, maybe turbo doing 1/4 mile passes you’d not need that. Some would say shuffle pins are a bandaid fix as a cover for using shitty parts just throwing parts together without balancing.
Or are you referring to steel backed main bearings? |
Sorry my poor english....(edit the post).. the post is about the steel main bore case ...... this repair is recommended or feasible when you want to extend the useful life of the case?....can this work be done on the four crankshaft bore?...the vw machinist in my country make the job for years in worn main bore type1 cases
Last edited by francoangellini on Mon Nov 28, 2022 7:50 am; edited 1 time in total |
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rugblaster Samba Member
Joined: March 31, 2016 Posts: 1163 Location: San Angelo, Texas
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Posted: Sun Nov 27, 2022 2:49 pm Post subject: Re: Steel main bore question |
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I recall something about kicking a dead horse. _________________ '69 Karmy, '69 Camper, Meyers clone, '65 drag bug, 10.78 @ 128 (sold it) '51 Dodge farm truck,
'09 MB E350 '18 MB E400, '65 Plymouth Valiant convertible and a '19 Ford F250 King Ranch (nicer, but dirty, farm truck)
VWoA factory trained line tech 75 till 90 or so
ASE Master Certification
VWoA Assoc. of Quality Technicians inductee (One of 25 in the five state southwest region)
La Confrerie des Chevaliers du Tastevin (San Angelo Chapter)
TCU ......GO FROGS!!!!!! |
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Zundfolge1432 Samba Member
Joined: June 13, 2004 Posts: 12452
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Posted: Sun Nov 27, 2022 5:08 pm Post subject: Re: Steel main bore question |
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This reminds me of a video someone posted here a couple years back about a fellow in India that welded broken crankshafts. He worked in a shop with dirt floor and primitive tooling. Also reminds me of what people have done in Cuba to keep things going. If your machinist has done this repair before successfully and he has a way to align bore and get the crush on bearings right then Who’s to say it won’t work. I think people shy away from this because of labor costs and the unfamiliarity |
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francoangellini Samba Member
Joined: January 10, 2012 Posts: 223 Location: Chile-South America
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Posted: Mon Nov 28, 2022 7:30 am Post subject: Re: Steel main bore question |
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Zundfolge1432 wrote: |
This reminds me of a video someone posted here a couple years back about a fellow in India that welded broken crankshafts. He worked in a shop with dirt floor and primitive tooling. Also reminds me of what people have done in Cuba to keep things going. If your machinist has done this repair before successfully and he has a way to align bore and get the crush on bearings right then Who’s to say it won’t work. I think people shy away from this because of labor costs and the unfamiliarity |
This began at the 80s early, when it was very necessary to repair the Brazilian type 1 kombi engines used by delivery companies, people transport and cargo with many kms engines... Currently they sell new type1 cases in my country (US1300), there are very few used cases in good condition for sale, this stell main bore work is currently worth US 200.....The machinist's son is still repairing cases with this method today....Some said that the temperature of the bearings was higher when resting on a steel ring....unfortunately there is very little information on the networks!!....My type3 case already has a lot of wear in the main (+0.040") , I am considering the option!!....the old maquinist son also repair Subarú boxer race engines!!
Last edited by francoangellini on Tue Nov 29, 2022 8:26 am; edited 2 times in total |
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Zundfolge1432 Samba Member
Joined: June 13, 2004 Posts: 12452
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Posted: Mon Nov 28, 2022 9:18 am Post subject: Re: Steel main bore question |
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francoangellini wrote: |
Zundfolge1432 wrote: |
This reminds me of a video someone posted here a couple years back about a fellow in India that welded broken crankshafts. He worked in a shop with dirt floor and primitive tooling. Also reminds me of what people have done in Cuba to keep things going. If your machinist has done this repair before successfully and he has a way to align bore and get the crush on bearings right then Who’s to say it won’t work. I think people shy away from this because of labor costs and the unfamiliarity |
This began at the 80s early, when it was very necessary to repair the Brazilian type 1 kombi engines used by delivery companies, people transport and cargo with many kms engines... Currently they sell new type1 cases in my country (US1300), there are very few used cases in good condition for sale, this stell main bore work is currently worth US 200.....The machinist's son is still repairing cases with this method today....Some said that the temperature of the bearings was higher when resting on a steel ring....unfortunately there is very little information on the networks!!....My type3 case already has a lot of wear in the main (+2mm) , I am considering the option!!....the old maquinist son also repair Subarú boxer race engines!! |
Necessity is the mother of invention 😀 |
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Alstrup Samba Member
Joined: July 12, 2007 Posts: 7177 Location: Videbaek Denmark
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Posted: Mon Nov 28, 2022 11:20 am Post subject: Re: Main bore steel job question |
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If a case it that worn, the lifter bores are most likely toast too. If a case needs that much love to come back to life i would find another case. _________________ https://www.thesamba.com/vw/forum/viewtopic.php?t=435993 |
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francoangellini Samba Member
Joined: January 10, 2012 Posts: 223 Location: Chile-South America
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Posted: Tue Nov 29, 2022 8:05 am Post subject: Re: Main bore steel job question |
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Alstrup wrote: |
If a case it that worn, the lifter bores are most likely toast too. If a case needs that much love to come back to life i would find another case. |
Yes, It is a very reasonable conclusion, I would not invest in a worn or damaged case, but on this occasion the reason for the reconstruction is due to the fact that the previous owner did not know how to do the job well; upside-down connecting rods&pistons, incorrect torques, wrong parts... (maybe main bore crank overheating)..... ..The lifters fit tight, and the rest case is in very good conditions.....in my post I was only looking for opinions and experiences about this main bore type reparation..
Thanks |
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modok Samba Member
Joined: October 30, 2009 Posts: 26740 Location: Colorado Springs
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Posted: Tue Nov 29, 2022 8:46 pm Post subject: Re: Main bore steel job question |
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If this steel sleeve DOES work well, then that does raise a lot of questions and it MIGHT be so, for all I know.
I would never attempt it because of the difference of expansion with heat...... BUT in truth I don't know what would ACTUALLY happen.
If it DOES work well then ......HOW? We would need to RE examine some beliefs.
If it does NOT work well why is your guy doing it so many times over many years.
It is still easier to make a bearing of whatever size is needed since the bearing only costs 20$ plus machine work.
If larger bearings are not available I might use an aluminum sleeve or make a bronze bearing.
If the bearing is steel shell then I might use a steel sleeve.
Putting a steel sleeve between an aluminum bearing and a magnesium case does not make sense, but if it DOES work.....then thanks for telling us. More detail of how to make it work or what is the reason for doing it would be nice to know. |
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Clatter Samba Member
Joined: September 24, 2003 Posts: 7527 Location: Santa Cruz
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Posted: Tue Nov 29, 2022 9:41 pm Post subject: Re: Main bore steel job question |
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Yes!
Nice!
Do you have details?
Is this steel main bore sleeve an interference fit of some kind?
Perhaps this raised groove is oversize of the groove in the steel sleeve to create a press fit?
I have a great old case with many tricks and only the main bore worn over.
This kind of treatment would seem ideal.
Was in Brazil years ago and it was impressive how many aircoolers were still on duty everywhere.
It doesn’t happen without skilled mechanics. _________________ Bus Motor Build
What’s That Noise?!? |
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francoangellini Samba Member
Joined: January 10, 2012 Posts: 223 Location: Chile-South America
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Posted: Sat Dec 03, 2022 3:44 am Post subject: Re: Main bore steel job question |
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Sharing the photos, maybe you have to see it as a curiosity .........IMO I think that having a reliable healthy stock vw case is the best option, or buy a good quality new one , but as I mentioned, this work has been done in my country for years without major problems, there are no studies that can exactly compare the real differences.
VW's aircooled market began in my country in the 50s, many German aircooled cars arrived, then Brazilian in the 70s and finally Mexican in the 90s. I am not a scholar who dares to recommend it, but being the "steel main bore" with more than 40 years of experience may be a sign!
I don't know where other countries do this job, but it is increasingly difficult to find good used or new parts....always thinking in a stock engine.
My best
Last edited by francoangellini on Mon Dec 05, 2022 4:15 am; edited 1 time in total |
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difrangia Samba Member
Joined: December 29, 2020 Posts: 58 Location: OK
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Posted: Sun Dec 04, 2022 9:41 am Post subject: Re: Main bore steel job question |
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As was mentioned above, 'Necessity is the mother of invention'. In many locations and in particular times a mechanical device that needs to be repaired when there are no replacements available or are completely beyond price availability. Critical thinking individuals with some degree of mechanic
ing/machining skills can perform mechanical feats that would not be remotely considered by someone who has access to availability and $$ to just replace with new and junk out the old.
I acquired a 61 FIAT 500D in 1974 with the two-cylinder 500cc engine scattered around inside the car. In that period the only parts that I could find for the FIAT were J.C. Whitney and I rebuilt that little engine for $17. J.C. soon after that quit carrying any parts for the car. I drove the little microcar for the next 13 years seasonally (If you have a low opinion of some AC VW's heaters, they're blast furnaces compared to the FIAT). I kept the little car going over that time frame, many times needing to do machining salvations and sometimes adapting other automotive parts for a repair. I worked in/around smaller machine shops for my whole career in a number of manufacturing fields and job titles and generally had access to machinery and materials. We often take the internet for granted now-a-days. Back then it was mainly Hemmings and Autoweek where you could occasionally find parts for oddball foreign cars.
If people have been doing the kind of fix that francoangellini is showing for decades and new stuff is not available or affordable, I'd judge it an acceptable fix for a lower stressed engine. I look at it as an opportunity to observe how other talented people overcome mechanical hurdles and glean some tid-bits that might be helpful in the future. I have, myself, done some fixes in the shop that worked out OK that I wouldn't consider telling people about. |
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pablovent Samba Member
Joined: July 14, 2010 Posts: 900 Location: Chile
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Posted: Mon Dec 05, 2022 4:49 am Post subject: Re: Main bore steel job question |
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Hi, I live in Chile, over the years I have rebuilt a few aircooled vw type 1 and 4's, I have also built three stroker engines that run great over the time.
At least 1/3 of the stock I have been dissasemble engines (after running many kms) have been repaired previously like this, and apparently everything seems to be very good, some have steel sleeves in only 3 main bore and others in all 4 like the photos.
As far as I know many vw machinist in my country ream the main bore only up to 1mm oversize even though up to 2mm bearings are available but experience with 2mm has not been fine due to poor end play useful life.
I can't recommend these solutions, but before the rebult work "the inspection case job" at least the new metal parts are still in place very firmly and with std measurements. |
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mcmscott Samba Member
Joined: March 12, 2010 Posts: 4848 Location: sanger ca
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Posted: Mon Dec 05, 2022 8:21 am Post subject: Re: Main bore steel job question |
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Are the inserts something they would sell seperate? _________________ There are no stupid questions, only stupid people,
68 Ghia
67 T-1
65 Notch
02 Mexican beetle
74 Thing
15 Long travel rail
07 Nomad
05 f-250 |
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pablovent Samba Member
Joined: July 14, 2010 Posts: 900 Location: Chile
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Posted: Mon Dec 05, 2022 9:49 am Post subject: Re: Main bore steel job question |
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mcmscott wrote: |
Are the inserts something they would sell seperate? |
No, the maquinist does all the work!.....Is that your question? |
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difrangia Samba Member
Joined: December 29, 2020 Posts: 58 Location: OK
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Posted: Mon Dec 05, 2022 10:05 am Post subject: Re: Main bore steel job question |
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The inserts would be the easy part. CNC lathe would spit them out. The longer that I look at this, the more I like it. It's be lovely to have a modern case with steel inserts cast in from the foundry if the expansion coefficient could be engineered. I'm sure it could, but I'm just a 'shadetree' engineer/mechanic, though I do have a mancave with a lathe, mill, etc. and an auto stall or two.
Last edited by difrangia on Tue Dec 06, 2022 7:01 am; edited 1 time in total |
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modok Samba Member
Joined: October 30, 2009 Posts: 26740 Location: Colorado Springs
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Posted: Mon Dec 05, 2022 6:33 pm Post subject: Re: Main bore steel job question |
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It is easier to make the insert to fit the bore. Same as we do with the thrust bearing.
I actually do these type of repairs.
Price is roughly 300, + 200$ extra for bearing bore that needs to be sleeved.
Takes a long time to do, because each one is different.
never had any request to do a vw.
Did it to a Porsche 924 probably closest to a vw, and even a Lamborghini once, they both burned up the thrust bearing.
But using aluminum for aluminum blocks, and iron for iron blocks, not steel.
A long time ago I took apart a vw engine I bought and it was bored 2mm over, the crank and block were ok so I just put it back together. The heads and rods were junk tho that was the problem. Sold it to a friend of mine and he drove it for several years. He got tired of it before it ever wore out in any way. These days VWs don't work very hard like they do in some parts of the world. They are retired now, only work part time. |
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RWK Samba Member
Joined: June 24, 2009 Posts: 1337 Location: S.W. MI
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Posted: Tue Dec 06, 2022 6:50 am Post subject: Re: Main bore steel job question |
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Puts new meaning to steel backed bearings! _________________ 73 Type 181
63 Type 113
63 Type 261- 428 071
62 Type 241-378 025 178 530 |
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