Tight crank bearing
Posted: Thu Jul 27, 2017 5:27 pm
Hi,
I start with the question and for those interested I add a bit of introduction of myself below. So my first question on the forum:
I started to assemble the crankcase of my G9 53/54 by putting the crankshaft into the drive side, loosely fastening the web (as instructions here on the forum ) and then pre-mounting the timing halve of the case. However, it do not want to fit. (I realized here that the reason for needing to drive the halves apart when dismantling was not from sticky gasket sealant and tight fit of the centre web, it is the timing side bearing fitting too tight in the outer races..). The bearing on the timing side of the crankshaft does not fit into the outer race in the timing side case.
I have searched the internet on how to handle this but I am still very unsure (as this is far beyond my comfort zone). Some questions:
1. Should I be expected to need to heat up the case to fit this bearing?(not to fit the outer race in the case, but to fit the bearing into the outer race)
2. Why would it be too tight, any common reasons? (it is now viciously centre-punched in place by massive marks approx. 10*2 mm, 0.5-1mm deep.. !! , could this be the reason for it to become tight?)
3. Before I took it apart the crank turned relatively easy, can I just heat up the case and put it together? (ignoring that it will be hell again to take it apart…). This will probably make the procedure with pre-fitting to align the centre web not possible..
4. Would a new bearing improve the situation?
5. How the heck can I get the outer race out of the case if I want to??There are no edges to grip it.
6. Could just removing the centre punch marks (how??), extracting the outer race (if possible) , and then refit the race with less centre punches help?
I apologize for the lengthy text. However, I still hope you can come with some thoughts and ideas on this. I am new to this so I probably missed out on detail, but I am happy to provide photos and further details.
Kind regards and glad to be in the forum!
eagle
ps pre-apologizing for newbi forum misstakes as well as lacking terminology...and experience and....ds
------------------------- intro---------------------------------------------------
Hi everyone on the forum! Just registered, read a lot the last few month, found the massive archive, founds loads of valuable input already…finally taking the step to ask for help.
Short intro of myself: Lifelong whish to ride motorbikes, but still no licence…(now in progress). Some weird ( source unknown ) liking of old motorbikes particularly British ones. Like to understand how they work. Last 2 year dissassembled my Honda (owned for 25yrs) down to frame (removed cyl + top, but did not split case) and managed to get it to run after assembly again.
Current time: Stumbled across (looking at ads every day for 2yrs..) a Matchless G9 Clubman from 53/54. Most of it in one (rusty) piece , but engine in boxes. Realized that I stepped into the deep end by buying one in pieces (I had promised myself not to buy one in pieces. If I dismantle something I usually can sort it out. But now..) but I could not resist ….
So, now I have a puzzle since some month ago. I have managed to sort a lot of the pieces correctly(I think..). I started to split the crankcase that was put together but looked dirty (which it was). Here the problems started I realized now when I started to put it together…see top.
I start with the question and for those interested I add a bit of introduction of myself below. So my first question on the forum:
I started to assemble the crankcase of my G9 53/54 by putting the crankshaft into the drive side, loosely fastening the web (as instructions here on the forum ) and then pre-mounting the timing halve of the case. However, it do not want to fit. (I realized here that the reason for needing to drive the halves apart when dismantling was not from sticky gasket sealant and tight fit of the centre web, it is the timing side bearing fitting too tight in the outer races..). The bearing on the timing side of the crankshaft does not fit into the outer race in the timing side case.
I have searched the internet on how to handle this but I am still very unsure (as this is far beyond my comfort zone). Some questions:
1. Should I be expected to need to heat up the case to fit this bearing?(not to fit the outer race in the case, but to fit the bearing into the outer race)
2. Why would it be too tight, any common reasons? (it is now viciously centre-punched in place by massive marks approx. 10*2 mm, 0.5-1mm deep.. !! , could this be the reason for it to become tight?)
3. Before I took it apart the crank turned relatively easy, can I just heat up the case and put it together? (ignoring that it will be hell again to take it apart…). This will probably make the procedure with pre-fitting to align the centre web not possible..
4. Would a new bearing improve the situation?
5. How the heck can I get the outer race out of the case if I want to??There are no edges to grip it.
6. Could just removing the centre punch marks (how??), extracting the outer race (if possible) , and then refit the race with less centre punches help?
I apologize for the lengthy text. However, I still hope you can come with some thoughts and ideas on this. I am new to this so I probably missed out on detail, but I am happy to provide photos and further details.
Kind regards and glad to be in the forum!
eagle
ps pre-apologizing for newbi forum misstakes as well as lacking terminology...and experience and....ds
------------------------- intro---------------------------------------------------
Hi everyone on the forum! Just registered, read a lot the last few month, found the massive archive, founds loads of valuable input already…finally taking the step to ask for help.
Short intro of myself: Lifelong whish to ride motorbikes, but still no licence…(now in progress). Some weird ( source unknown ) liking of old motorbikes particularly British ones. Like to understand how they work. Last 2 year dissassembled my Honda (owned for 25yrs) down to frame (removed cyl + top, but did not split case) and managed to get it to run after assembly again.
Current time: Stumbled across (looking at ads every day for 2yrs..) a Matchless G9 Clubman from 53/54. Most of it in one (rusty) piece , but engine in boxes. Realized that I stepped into the deep end by buying one in pieces (I had promised myself not to buy one in pieces. If I dismantle something I usually can sort it out. But now..) but I could not resist ….
So, now I have a puzzle since some month ago. I have managed to sort a lot of the pieces correctly(I think..). I started to split the crankcase that was put together but looked dirty (which it was). Here the problems started I realized now when I started to put it together…see top.