rebuilding cranks

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zinc2u
Posts: 0
Joined: Tue Jan 15, 2013 4:45 am

rebuilding cranks

Post by zinc2u »

Hi Bob,
    You will need 6x16 and 6x10 bearings which can be purchased from a bearing
supplier.  I suggest you disassemble the crank and inspect the bearings with a
microscope to determine the damage done to the bearings.
     To quote the message from GNB;
"Bottom line, rebuilding these cranks can concievably/ technically be done, but it's a lot harder and more involved than you realize."
This is very true.  But if you have one of these cars and you need a crank,  you are in a tough position and it is going to take a lot of time and effort on your part and/or a bunch of money to get a crankshaft which is usable.  Rebuilding the crank is going to be expensive.  The approach which most have taken (including myself) is to find two cranks which each have one good connecting rod section,  oress them apart,  inspect the pieces,  press back together one usable crank.  You don't have a rebuilt crank,  you just have a used crank which buys you some extra time.
Oversize wrist pins were available (from Honda) for the Honda 600.
You could take your crank to an auto machine shop and have them hone the connecting rod to fit the oversized wrist pin.  This could be done without disassembling the crankshaft.   If you want oversize wrist pins now,  you will need to find someone who has NOS or special order through a piston manufacturer.
The bearings can be located from a bearing distributor or NOS from a collector.
If you need replacement con rods,  you will need to remove them from another crank or give lots of $$$$ to a connecting rod mfg and have them build you a set.
If you plan on pressing the crank apart with your equipment,  I suggest you collect some extra cranks and pick one which is seriously damaged to practice on your press.  The toughest part is getting the part properly supported and horizontal so you can press it apart.  The first time I tried it,  I had it at a business with an 80 ton press and they were unable to press it apart and suggested it may have been assembled by heating the outer section and cooling the center section.  Then I had a friend show me how it is done and he used a 20 ton press.  It was scary....... the crank was under 20 tons of pressure and nothing had budged.  I was expecting the crank to just slowly come apart but it gave no visible indication it wanted to come apart and it had a lot of pressure on it.  My friend started slowly taping around the crank with a hammer and the crank made an exploding sound as it came apart ..... it had 20 tons of force on it and you could get injured from the bearings and pieces flying around.  So,  if you are working on it yourself,  wear eye protection and think about which parts of your body are exposed in case the crank explodes and sends out fragments.  Also,  have a catch system to capture the parts (e.g. bearings) when the system comes apart.
The reason I suggest practicing on a bad crank is to develop a technique before you work on a partially good crank.  If you don't have the crank properly supported and horizontal,  you could end up damaging the connecting rods and then you have just wasted a good part.
I also would check with motorcycle shops to see who works on their cranks.  And then let them do it for you.
When you press the crank together again,  you have another challenge....getting the two pieces properly aligned.  You need the equivalent of a V-block to line up the sections.  If you are off by one spline,  you have to redo the work.
good luck,
Dale
> I have
> a few pullers but this would probably require a press. I > noticed in the > parts manual this uses a 6x16 bearing. I also noticed > this part was still > available for other earlier honda models. Do you > know if this will work?
> There was a group comment earlier that some
> components are interchangeble
> with a early honda cb450, though there
> wasn't any confirmation. I do plan
> to replace all of the cam chain
> contact components (chain, rollers,
> slippers, etc.) because I did
> notice a lot of wear. I still have to try to
> find those replacement
> parts.
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sangreyb
Posts: 0
Joined: Sun Feb 15, 2009 10:02 pm

Re: rebuilding cranks

Post by sangreyb »

Dale,
Thanks for the info. Right now it appears the bearings are fine. The
crankshaft center stator side bearing (small one) has some axial play
due to a .030" gap. Is this supposed to be like this? There is a
dowel locater pin in both of them. I actually finally got the pistons
out and the cylinder side walls appear ok. I have a new piston set
and they are oversized so I plan to take the cylinder barrel to a
machine shop to have them check the sleeves and bore them out for me.
Next I still need gaskets and all the wearable cam parts.
Thanks for all of the help,
Bob
> Hi Bob,
> You will need 6x16 and 6x10 bearings which can be purchased from a
> bearing
> supplier. I suggest you disassemble the crank and inspect the bearings with
> a
> microscope to determine the damage done to the bearings.
> To quote the message from GNB;
> "Bottom line, rebuilding these cranks can concievably/"Bottom line,
> rebuilding these cranks can concievably/technically be done,
> This is very true. But if you have one of these cars and you need a crank,
> you are in a tough position and it is going to take a lot of time and effort
> on your part and/or a bunch of money to get a crankshaft which is usable.
> Rebuilding the crank is going to be expensive. The approach which most have
> taken (including myself) is to find two cranks which each have one good
> connecting rod section, oress them apart, inspect the pieces, press back
> together one usable crank. You don't have a rebuilt crank, you just have a used
> crank which buys you some extra time.
> Oversize wrist pins were available (from Honda) for the Honda 600. You
> could take your crank to an auto machine shop and have them hone the connecting
> rod to fit the oversized wrist pin. This could be done without disassembling
> the crankshaft. If you want oversize wrist pins now, you will need to find
> someone who has NOS or special order through a piston manufacturer.
> The bearings can be located from a bearing distributor or NOS from a
> collector.
> If you need replacement con rods, you will need to remove them from another
> crank or give lots of $$$$ to a connecting rod mfg and have them build you a
> set.
> If you plan on pressing the crank apart with your equipment, I suggest you
> collect some extra cranks and pick one which is seriously damaged to practice
> on your press. The toughest part is getting the part properly supported and
> horizontal so you can press it apart. The first time I tried it, I had it
> at a business with an 80 ton press and they were unable to press it apart and
> suggested it may have been assembled by heating the outer section and
> cooling the center section. Then I had a friend show me how it is done and he used
> a 20 ton press. It was scary....... the crank was under 20 tons of pressure
> and nothing had budged. I was expecting the crank to just slowly come apart
> but it gave no visible indication it wanted to come apart and it had a lot
> of pressure on it. My friend started slowly taping around the crank with a
> hammer and the crank made an exploding sound as it came
apart ..... it had 20
> tons of force on it and you could get injured from the bearings and pieces
> flying around. So, if you are working on it yourself, wear eye protection
> and think about which parts of your body are exposed in case the crank explodes
> and sends out fragments. Also, have a catch system to capture the parts
> (e.g. bearings) when the system comes apart.
> The reason I suggest practicing on a bad crank is to develop a technique
> before you work on a partially good crank. If you don't have the crank properly
> supported and horizontal, you could end up damaging the connecting rods and
> then you have just wasted a good part.
> I also would check with motorcycle shops to see who works on their cranks.
> And then let them do it for you.
> When you press the crank together again, you have another
> challenge....getting the two pieces properly aligned. You need
the equivalent of a V-block to
> line up the sections. If you are off by one spline, you have to redo the
> work.
> good luck,
> Dale
> I have a few pullers but this would probably require a press. I
> noticed in the parts manual this uses a 6x16 bearing. I also noticed
> this part was still available for other earlier honda models. Do you
> know if this will work? There was a group comment earlier that some
> components are interchangeble with a early honda cb450, though there
> wasn't any confirmation. I do plan to replace all of the cam chain
> contact components (chain, rollers, slippers, etc.) because I did
> notice a lot of wear. I still have to try to find those replacement
> parts.
> **************You can't always choose whom you love, but you can choose how
> to find them. Start with AOL Personals.
> (
http://personals.aol.com/?ncid=emlcntuslove00000002)
zinc2u
Posts: 0
Joined: Tue Jan 15, 2013 4:45 am

Re: rebuilding cranks

Post by zinc2u »

Hi Bob,
    Are you referring to a main bearing or a con rod bearing?  For the con rod,
this amount of axial play is acceptable.  It would not be acceptable for the main
bearing (if it is the area I was thinking you meant).  Anyway, the Honda Sedan
Shop Manual gives you all the details on checking the crankshaft and the serviceable
limits.  I thought an electronic copy of the Sedan Shop Manual was on one of
the group's site or at Steve's page (click here ).
I did a quick look and did not see it
on Steve's page but maybe it is there and I am not very observant today.  The info
you need starts at page 4-41 of the sedan shop manual (thick white and blue covered book).
good luck,
Dale
> Thanks
> for the info. Right now it appears the bearings are fine. The > crankshaft > center stator side bearing (small one) has some axial play > due to a .030" > gap. Is this supposed to be like this? There is a > dowel locater pin in > both of them. I actually finally got the pistons > out and the cylinder side > walls appear ok. I have a new piston set > and they are oversized so I plan > to take the cylinder barrel to a > machine shop to have them check the > sleeves and bore them out for me.
> Next I still need gaskets and all the
> wearable cam parts.
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Robert Sangrey
Posts: 0
Joined: Mon Feb 23, 2009 8:26 am

Re: rebuilding cranks

Post by Robert Sangrey »

Dale,
Thanks for the information. looks like when I got the pistons out the main bearing shaft moved moved slightly out. It is in spec by dial but will need to be pressed back together to tighten the clearance. The conn rod clearance was fine.
Again thanks for the help. The sedan manual is much more informative then the coupe manual.
Bob
From:
"goinhm@..." To:
anzhonda600owners@yahoogroups.com Sent:
Sunday, February 22, 2009 4:22:09 PM Subject:
Re: [anzhonda600owners] Re: rebuilding cranks
Hi Bob,
    Are you referring to a main bearing or a con rod bearing?  For the con rod,
this amount of axial play is acceptable.  It would not be acceptable for the main
bearing (if it is the area I was thinking you meant).  Anyway,  the Honda Sedan
Shop Manual gives you all the details on checking the crankshaft and the serviceable
limits.  I thought an electronic copy of the Sedan Shop Manual was on one of
the group's site or at Steve's page (click here ).  I did a quick look and did not see it
on Steve's page but maybe it is there and I am not very observant today.  The info
you need starts at page 4-41 of the sedan shop manual (thick white and blue covered book).
good luck,
Dale
> Thanks for the info. Right now it appears the bearings are fine. The > crankshaft center stator side bearing (small one) has some axial play > due to a .030" gap. Is this supposed to be like this? There is a > dowel locater pin in both of them. I actually finally got the pistons > out and the cylinder side walls appear ok. I have a new piston set > and they are oversized so I plan to take the cylinder barrel to a > machine shop to have them check the sleeves and bore them out for me.
> Next I still need gaskets and all the wearable cam parts.
You can't always choose whom you love, but you can choose how to find them.
Start with AOL Personals.
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