Date: Sun, 7 Apr 2002 12:47:13 -0500
Reply-To: Stan Wilder <wilden1@JUNO.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Stan Wilder <wilden1@JUNO.COM>
Subject: Re: Boston Bobs tale of an engine stripper or .19 Main bearing
info was Flickerin oil light on 85 auto
Content-Type: text/plain; charset=us-ascii
Karl.
Sounds like your horse has left the barn already.
As for me I'd set the idle up just a little bit and run 20/50 to get that
false sense of security you need while saving up for a new engine.
If you don't have other problems you might stretch another 20K out of
that engine.
Stan Wilder
83 Air Cooled Westfalia
On Sun, 7 Apr 2002 10:29:35 -0700 Karl Wolz <wolzphoto@WORLDNET.ATT.NET>
writes:
> Bob,
>
> Great article. Only problem is you never answered the original
> question
> about oil viscosity!
>
> I've been advised to never use multi vis oils (yes - a long time
> ago) and
> also that modern low vis oils are not the best for the relatively
> low tech
> vw engines we use. The chart in the owner's manual does not go
> above 100
> deg F., and I live in Phoenix (land of 110 - 115), so I use 30
> weight in the
> winter and go to 40 weight in the summertime. I use Valvoline
> Racing Oil
> exclusively.
>
> Your comments on out of round journals and related OP problems tend
> to go
> hand in hand with my use of the 40 weight.
>
> Comments?
>
> Thanks,
>
> Karl Wolz
>
> ----- Original Message -----
> From: "Robert Donalds" <bostneng@FCL-US.NET>
> To: <vanagon@GERRY.VANAGON.COM>
> Sent: Sunday, April 07, 2002 9:33 AM
> Subject: Boston Bobs tale of an engine stripper or .19 Main bearing
> info was
> Flickerin oil light on 85 auto
>
>
>
>
>
>
>
> Mike wrote
>
> My 85 westy is a new one to me. my first wasser at that. it's got
> 168,000
> with 75,000 on a rebuilt engine. My first oil change is coming up.
> Can
> anyone suggest a particular oil and or viscosity for use during the
> hot
> summer months?
>
> Mike and fellow vanagon types
>
> In my time I have taken a couple of 1.9 engines apart and I would
> like to
> share with you some of the things I have seen and learned. Most 1.9
> engines
> are pretty tired by the time I get them in fact they are mostly
> turned in
> cores in exchange for fresh rebuilds but some come from stripped
> vans that
> had other problems. The one thing that is consistent in all 1.9
> engines is
> that the crank bore in the case are out of spec. The specifications
> for the
> crankshaft bore size and the amount bearing crush is not listed in
> any book
> I have seen. This leaves allot of room for a judgment call based on
> past
> experience or advise from others and lack of other options. Some
> would tell
> you that if the bearing sits in the web and seems tight then that's
> OK and
> if the engine does not bind when you tighten the case bolts then you
> are
> good to go. Now we are getting to the difference between going threw
> an
> engine and rebuilding an engine. As I said not knowing the specs
> makes the
> job a little tricky so in order to understand the intent of the
> manufacturer
> I have looked back at some of the older engine specs to see if there
> is any
> details that we can use to interpret the intent of those who
> designed the
> WBX engine. The type 2/4 engine and the bug engine do have specs for
> the
> case bores and wear limits listed in the without guesswork book. The
> without
> guesswork book was handed out to techs as they went threw the
> dealer
> training programs back in the sixties and seventies. As it turns out
> there
> is some good info we can use to determine the intent of the
> designers of the
> WBX engines. First the nose bearing is the same on all flat 4 vw
> engines
> since 1961 right threw to the 91 WBX engine. The size of the bore
> for the
> nose bearing is 50 mm to 50.03 mm. and the wear limit is 50.04 mm.
> The next
> thing I noticed is that the Main bearings bore sizes are all in
> round
> numbers. Yah got to love those Germans need for order and
> straightforward
> simplicity. The two middle main bearings bores are in fact the same
> size on
> the bug main bearings bores as they are on the 1.9 WBX engine and
> that is 65
> mm. with a wear limit of 65.03 mm. The type 2/4 main bearings bores
> are the
> same bore size as the rear main WBX bearing no big surprise! ( no
> its not
> the same bearing ) The rear main bearing bore for the type 2/4
> engine is 70
> mm with a wear limit of 70.03 mm. With all of that in mind we can
> now go
> back and look at the WBX block and use these dimensions to determine
> the
> condition of the used 1.9 cases. The next dimensions we need to
> determine if
> the case is in useable condition is the actual size of the bearings
> and then
> we can do the math and determine the bearing crush IF ANY!!!
>
> At this point I am going to repeated the statement I made at the
> beginning
> of this rant. The one thing that is consistent in all 1.9 engines is
> that
> the crank bore in the case are out of spec. With that said I can
> tell you
> that the new OEM 1.9 bearings I still have on the shelve (no they
> are not
> for sale so don't ask) are 3 ths or .12 mm larger than the main
> bearing bore
> specs I have listed above. So with all this we can do the math and
> see that
> the case crush on the bearing is intended to be between .002ths.
> And
> .003ths.
>
> When the bearings do not have the proper crush or the bearings are
> loose in
> the block as is the case with older high mileage WBX engines and
> with engine
> that have just been redone rather than rebuilt then the engine will
> have
> low oil pressure at warm idle.
>
> Measuring the WBX block to determine the size of the crank bore
> can't be
> done without a good bore micrometer and a lot of practice. The other
> thing I
> has noticed is that the case halves tent not to bolt together as
> intended.
> The WBX block has two locating pins as do all VW air and
> water-cooled flat 4
> engines this is done to hold the block in place so it can be
> machined and so
> the halves will return to there machined position when assembled.
> Over time
> the case halves do shift you can in fact feel the shift at the
> parting line
> when a used case is bolted and torqued together without any bearings
> in
> place. The case shift is commonly .002 to .005 ths. at the parting
> line and
> this can vary from end to end. I have tried to use a block of wood
> and
> hammer to align the halves as I bring the case halves together
> before I
> align bore with limited success and have had to developed tooling do
> get the
> cases halves back where they belong in order to align bore. This is
> important because when the case is not properly centered the cam
> bore and
> oil pump bores will be permanently misaligned by the new bearings in
> the
> nice round holes for the main bearing once we align bore the crank
> bore. One
> other note about used 1.9 blocks is that the thrust surface takes a
> pounding
> and the new main bearings can be loose and the case needs a thrust
> cut. You
> bug types might remember that the bug blocks commonly needed the
> thrust cut
> to keep the rear main bearing from moving.
>
> Now that I have told you all this great info on 1.9 cases and
> bearings I
> need to tell you that the nice folks at Kolbenschmdt have not
> produced Main
> bearings for the 1.9 WBX engine for the last 3 years. There has
> been no
> news from across the big pond as to when they intend to make a
> production
> run if ever. The demand has not diminished so a few brave soles have
> started
> making 1.9 rear main bearings and using the bug bearings for the
> other mains
> bearings. I at first did not want to use these custom made bearings
> for fear
> of the dreaded unknown. As time went by and fellows like Jim
> Digennaro
> former editor of limbo needed main bearings we got brave and tried a
> set or
> two more than a year ago and now many more sets and the engines are
> still
> going strong with no signs of any oil pressure issues.
>
> I have also in the last year made changes to my boring bar that
> allows me
> to align bore and thrust cut 1.9 .20 and 2.1 engine blocks and I now
> offer
> these services hear at the engine exchange. I also stock 1.9 main
> bearings
> in most common dimensions and I have also had made 20 and 40 over
> and thrust
> cut bearings for the discrimination engine builder.
>
> Be aware that with some aftermarket bearing the tolerances are not
> what they
> should be and the bug bearing set aren't much better so measure
> measure and
> remeasure and remember that they say about assuming
>
> All rights reserved
>
> Bob Donalds
>
> Boston Engine Exchange
>
> The Engine Exchange Deluxe
>
> http://www.bostonengine.com
>
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