Date: Wed, 3 Dec 2003 21:18:30 -0500
Reply-To: ROBERT DONALDS <donalds1@VERIZON.NET>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: ROBERT DONALDS <donalds1@VERIZON.NET>
Subject: Fw: 2.1L Align bore and main bearings
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----- Original Message -----
From: "ROBERT DONALDS" <donalds1@verizon.net>
To: "Curt Lewis" <curtis-l-lewis@CFL.RR.COM>
Sent: Wednesday, December 03, 2003 9:14 PM
Subject: Re: 2.1L Align bore and main bearings
> Curt
> the crankshaft can be ground .010ths or 020ths as needed I have cranks on
> hand in both STD and 010 ths. we can do exchange if your core will grind
to
> 010ths I can if needed aignbore your block to 020ths over. no 040ths
> bearings are available. I have all available main bearing sizes on hand
and
> can offer you some tech support along with your parts order. You can ship
> the block and crank to me and I can go over the parts or I can offer you a
> longblock assembled.
> There are no numbers published anyplace for the main bearing bores on the
> 2.1 case. Unlike the 1.9 main bearing bore sizes I have posted
> to the list I hesitate to offer you numbers for a couple of reasons. The
> trimetal composition main bearings needs a higher crush fit. They are also
a
> 1 piece rolled bearing with a tongue and groove joint. Also because of
the
> way they are made, they are not round enough to say what size they are
> without averaging the measurements. Plus I have yet to find some kind of a
> commonly understood crush fit this type of bearing requires. Most mains
> bearing in today's engines are a spilt type and this rolled bearing is
> commonly pressed into a cast iron block for something like a camshaft. The
> other consistent issue is that I have never seen what I would consider a
low
> mileage or good used block that measured in round numbers ( metric ) All
> other VW blocks are 60.MM or 65. MM. So this is a tricky one I don't think
> the case wear or bearing saddle wear can account for the odd sizes I am
> seeing. I have spent to much time and effort to give away what I know
about
> the sizes of the 2.1 main bearing webs but send it to me and I will set
you
> straight.
> The next problem I encountered is that most aluminum VW blocks have
some
> shift. This shift needs to be corrected for in order to measure the block
> near the parting line and determine if the main bearing web is itself
> shifted or just the halve of the block. To do this I have developed a set
of
> tapered block alignment tools they are installed into the front and rear
> seal surfaces and they true the seal bores as I snug the nuts that hold
the
> block together. The alignment tools are then removed and the block is
> torqued for measurement and align bored if needed. The tapered alignment
> tooling acts much like the main bearings would in bringing the block back
> into true.
> Using my tapered alignment tools I have assembled Canadian remand
> blocks and I have seen some that had .005ths case shift and have gotten
> alignbored that way. The block at the crank main bearing bore is now
offset
> .005ths. and when the main bearings are installed and the halves are
forced
> to maintain this shift in this position and the cam bore is permanently
> misaligned. The problem with this might not be seen as the block is bolted
> together In other words it would still spin without any noticeable
binding.
> however what do you think happens when the block heats up and the cam
> bearings halves are misaligned .005ths IT BINDS and this makes the oil
temp
> soar so in a very short time you have lots more than the intended .0015ths
> cam bearing clearance.I would consider this block junk because there is no
> second over size outside diameter main bearings.
> I let me know how I can help you could send you parts in for inspection
and
> repair. I am a full service engine rebuilder and offer parts a competitive
> prices and tech support to my customers.
>
> Bob Donalds
> Boston Engine Exchange
> 1 508 358 6264
> http://www.bostonengine.com
>
> all rights reserved
>
>
>
>
>
>
>
>
>
>
>
>
> ----- Original Message -----
> From: "Curt Lewis" <curtis-l-lewis@CFL.RR.COM>
> To: <vanagon@GERRY.VANAGON.COM>
> Sent: Wednesday, December 03, 2003 5:13 PM
> Subject: 2.1L Align bore and main bearings
>
>
> > I am going to rebuild my 2.1L engine in my '85 vanagon. I am not new to
> the
> > list but unsubscribed probably a year ago because the project got put on
> the
> > back burner. The times I did use the list server in the past, I got
great
> > responses.
> >
> > The engine is tore down and the #1 main bearing was chewed up pretty
good.
> > Running my fingernail across the #1 bearing journal of the crankshaft it
> > catches. So either I need a new crankshaft or get this one turned down
> > and/or polished. Turn down or get a new one? I'd like new but will
have
> to
> > make that call later.
> >
> > My concern is align boring the crankcase and then deciding which
bearings
> I
> > need. I did a search of the archives of the list and some of the hits
> came
> > up about how to figure which bearing is needed and getting the right
> amount
> > of bearing crush. I'm still confused on the proper way to determine it.
> I
> > do understand that deciding which bearings I need depends on if I get a
> new
> > crank or reworked crank.
> >
> > How do I determine proper bearing size, with respect to the case, and
> still
> > get proper bearing crush?
> > Should I send off the case and shaft to someone and let them figure it
> out?
> > Has anyone sent off their case and shaft to have them worked on?
> > If so who was it and how much did it cost? Or what should the ballpark
> cost
> > be?
> > Should I skip the align bore and just get a new or reworked crankshaft?
> (I'm
> > thinking due to the damage of the bearing that an align bore might be
> > warranted.)
> > Does anyone know of a good machinist in the Melbourne/Orlando/West Palm
> > Beach Florida area?
> >
> > I plan on buying most if not all things new, but I feel I can't move
> forward
> > on anything until I get a good idea of what I need to do and how I'm
going
> > to get it done with respect to the case and crankshaft. I know this has
> > been hashed and rehashed on this list, but I just can't seem to find the
> > info I need.
> >
> > Any thoughts would greatly be appreciated. Thanks.
> >
> > Curt
> >
>
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