Jay,

The 20B utilizes a split shaft.  You're going to have to separate
 it inorder to disassemble the engine.  Bob Darrah built a
 splitter tool from athreaded shaft and a 1" thick bar of steel.
 The threaded shaft will needtomatch the threads in the #1
 lobe on the crank, 18mm if I recallcorrectly.Thread the shaft
 into the lobe, slide the 1" bar over the other end ofthe
 threaded shaft until it fits snug against the nose of the eccentric,
 putanut on the threaded shaft to tighten it all down.  You
 may want to use asoft aluminum or brass spacer so you don't
 bugger up the end of theeccentric.  Tighten the nut until it
 cocks the 1" bar a little, then taptheother end of the bar
 with a hammer and it should come right apart, atleastthat's
 how it has worked for me twice.  Now you can finish disassemblingthe
engine.  Remember the sequence for when you are ready to re-
 assemble it.

Mark S.

Mark--do you have a photograph of the 3-rotor eccentric separation
 tool  installed on the eccentric?

Steve Beckham

Steve,

Yes, see the last picture in the group.  The TR (threaded rod) screws
into
female threads in the #1 lobe (the removable one).

I should have mentioned that the picture doesn't show the BN (big
 nut)that gets threaded onto the other end of the TR.  The purpose
 of the BN  isto lock the BB (big bar) down against the end of the
 e-shaft.  I  recommendyou put a piece of softer material (like
 aluminum or brass) between the  BBand the e-shaft to keep from
 damaging the threads.

Once it is assembled, you take a BH (big hammer) and smack the
unsupported
end of the BB.  The #1 lobe should pop right off.

Mark S.

I'm having a heck of a time finding an 18mm bolt with 1.5mm pitch
 longenough to use on getting the E shaft split. Looks like I'll
 befabricating/jury rigging/welding something.

Jay

Welding. Not all bad. The loads are not that high.

Paul Lamar

Jay,

That's the problem I encountered.  As I stated earlier, the one shown
 in
the
picture was built by my machinist friend Bob Darrah.  If you take
 acloselook at the threaded rod, you can see that he turned
 down the largerdiameter and threaded it for 18mm.

Being a welder (not a machinist) I had planned on welding a bolt
 to athreaded rod.  Paul's correct, the loads aren't that great.

Also, make the hole in the BB a little oversize so it can move a
 little.

Mark S.

Tiffany Perez

Spahr Metric, Inc.

421 McGhee Road

Winchester, VA 22603

PH: 540-678-3815 Ext 101

Fax : 540-678-3819

I just ordered an 18 x 1.5 mm threaded rod from the company
 above. It'sthree times the length I need but it's only $22. I
 thought I'd mentionitincase any one else was looking for
 parts to separate the E shaftextensionwith. They have access
 to shorter bolts of that size but you have to buyabox quantity.

Jay

Jay,

Good info on the 18mm all-thread.  Hope you ordered a couple of
 18mm nuts  too.

Do you have a chunk of 1" thick bar stock?  It should be approx.
 10-12" x  3".  You'll also need a drill press (or torch) to
 drill/cut a big hole in  the 1" bar stock.

Mark S.

Mark,
Yes I got nuts to go with the rod and I also have a piece of steel
channel
stock. I thought it might be as stiff as a thicker piece of rectangle
stock.
I already drilled a slightly over size hole in it, with a $20
 drill bit  I'll  probably never use again.

Jay

Jay,

If you were local, I would loan you this one.  On the brighter
 side, nowyou'll have your own puller, just in case you ever need
 to go through yourengine in the future.  Let's hope you never
 need to use it again.  Goodluck!

Mark

Slightly off topic question.
With this email newsletter format, is there any kind of archive that
someone
could search through, rather than asking questions that some of
 you moreknowledgeable guys may be getting tired of answering?

Jay

Other than the web site nothing. I don't mind as things change
 and we areconstantly getting new readers. For new readers please
 read the entire website first and then ask questions. I notice
 some people don't read the website.Not you Jay :) We don't
 have anything on overhauls other than a link to theshop manuals.
 Unfortunately there is no english shop manual on the 20B thatI
 know about. Videos yes but no printed 20B shop manuals. After a 11 years
I am still learning. I have a 20B but it has not been disassembled.

If I get some questions that are not covered by the web site I
 will updatethe web site. I average some kind of update about once
 a week. Some timesit is just to add stuff to the for sale section.

Paul Lamar

I'm still trying to get the 20B E shaft extension apart.
I have pretty much all the torque I can get on the nut with no results.
I attached some photos, does it look like I'm doing this
 correctly?I want to  make sure before I put a pipe(for leverage)
 onto the wrench I'mtorqueing the nut with.The black piece
 between the big bar and the end of the shaft is there justto
 protect the threads and spread the load.

Jay

I would take the rubber out of there and replace the large screw
 in the endof thee-shaft to protect it. Take up the tension
 again and smack the iron anglewith a hammer.The shock should
 cause the e-shaft to vibrate and come apart.

The angle iron might not be stiff enough to do this as the guys
 have beenusing a bar of steel instead of angle iron.

Paul Lamar

 Jay,
 The nut doesn't have to be all that tight, just tight enough so that
 the steel bar isn't sitting flat on the end of the e-shaft.  Just to
 be perfectly clear, you strike the end of the bar opposite the nut/threaded
 rod.

 I have to agree with Paul to replace the rubber with a piece of
 aluminum or brass.  I would bet that the angle iron isn't stiff
 enough for the job.  It may also be too long and thereby absorbing
 much of the energy of the hammer blow.

 Also, you want the threaded rod as close to the C/L of the e-shaft
 in order to get the most leverage for when you strike the opposite end.

 Mark

 Thanks for everything so far gentlemen. That "plastic" was a metal bracket
 but I removed it and used the E shaft nut instead for my latest
 attempt. I also cut my angle bar into thirds, and used two pieces
 one on top of the other. Not as stiff as a single piece I'm sure but
 presumably better than before. In any case it still didn't work. I
 banged on it with a regular hammer and a dead blow hammer, my
 extension hasn't even budged. Either Bob with the spitfire is be
 leading a charmed life, or my extension is welded on. :)

 I'm going to try and pry it off tomorrow.
 http://www.wut2c.com/Knowledge/Automobile/mazda_20b_rebuild_tips.htm

 If that doesn't work, I'll officially be desperate.

 Jay

 You need the thick steel bar Jay. Two angles back to back damp out
 the vibration. Also a carpenters hammer usually does not work. It
 does not trigger the intense vibration you need. Try a ten pound
 sledge. Also warm it with a butane torch. I don't recommend a dead
 blow hammer. You need that metal to metal shock. We have the same
 problems with flywheels. The answer is always the same. A larger hammer.

 Paul Lamar


Wasn't it Truman who said "walk softly and carry a big stick"

Dale Davies


Teddy Roosevelt..


Matt-