The BSA A7-A10 Forum

Technical => Clutch, Primary, Gearbox => Topic started by: Cider1 on 01.11. 2011 17:14

Title: Pushrod problem!!
Post by: Cider1 on 01.11. 2011 17:14
Hi
I've been having some issues with clutch adjustment on my '58 Flash.  Do you think that this pushrod could be the cause of the problem?

Only joking.  This is the lever end of the rod which I'm about to replace.  I think this is down to not having a hardened end, if you pardon the expression!!!

Cheers
Frank
Title: Re: Pushrod problem!!
Post by: muskrat on 01.11. 2011 19:18
But if you push it through the mainshaft the other way it should straighten out. *eek* *eek*
Cheers
Title: Re: Pushrod problem!!
Post by: RichardL on 01.11. 2011 22:29
I wonder if there will be any discoloration on the ends of the new rod to indicate they have been hardened? Couldn't you just grind this down and harden it yourself with a mineral or fish oil quench?

By the way,  Frank,  I think it's been some time since you've been on,  so welocme back.  How's that music career doing?

Richard L.
Title: Re: Pushrod problem!!
Post by: Cider1 on 02.11. 2011 12:32
Hi Richard
The old rod doesn't look as though it was hardened.  I know the new one has because I've just done it.
The music career has slowed down a bit recently because our singer decided that after 16 years and over 800 gigs he wanted to do something different so at the moment we are busy auditioning for a replacement.  Watch this space!!

cheers
Frank  *beer*
Title: Re: Pushrod problem!!
Post by: dpaddock on 19.11. 2011 17:36
Frank -
Are you sure you have a steel rod there? Is the steel ball still embedded in the end of the adjusting screw? I've never seen a pushrod end deformed that way. There's a serious other problem involved here if that's a steel rod and the other pieces are proper. In fact, the axial force on a steel pushrod is well below the force needed to deform it (except for the small indentation made by the adjusting screw ball).

David
Title: Re: Pushrod problem!!
Post by: bsa-bill on 19.11. 2011 19:30
Quote
we are busy auditioning for a replacement.  

"Tra la la twiddle de dee dee" - "I was lost in France?" - "tie me kangaroo down mate" - oh nearly forgot "Men of Harlech "

OK I suppose you'll let me know  *contract* *whistle*
Title: Re: Pushrod problem!!
Post by: Cider1 on 22.11. 2011 15:44
Hi David
It was definitely a steel rod.  I don't know what type of steel but I don't think it was hardened.  The replacement that I've made works very well.  I can now select 1st gear with no clunk and even get neutral easily with the engine running.

Hi Bill

Quote
"Tra la la twiddle de dee dee" - "I was lost in France?" - "tie me kangaroo down mate" - oh nearly forgot "Men of Harlech "

Thanks for auditioning but you're too late, the vacancy has been filled.  We're now busy rehearsing getting ready to start gigging again in the early new year.

Cheers
Frank   *smile*  *beer*

Title: Re: Pushrod problem!!
Post by: LJ. on 22.11. 2011 16:59
Looking at that rod...  It might be a good idea to see if you can fish out any bits of broken off steel by using one of those telescopic magnets. You wouldn't want any bits to get in the speedo gearing.
Title: Re: Pushrod problem!!
Post by: mrshells on 08.04. 2012 18:41
any one the correct measurement for the length of the  pushrod lease ?
Title: Re: Pushrod problem!!
Post by: chaterlea25 on 08.04. 2012 19:37
Hi MrShells,
It depends on which type of clutch is fitted ??
I just buy a 13" length of silver steel from my local engineering supplier and make my own
That way you can adjust the length so as to get the clutch arm at the correct angle etc which gives a better clutch action
HTH
John O R
Title: Re: Pushrod problem!!
Post by: trevinoz on 08.04. 2012 22:37
Hi John,
                 Do you harden the ends on your pushrods?
I make them out of bright shafting and harden the ends with "Hardite".

 Trev.
Title: Re: Pushrod problem!!
Post by: wilko on 08.04. 2012 23:44
This has only happened because of constant contact, instead of having freeplay. Even mild steel wouldn't do this if adjusted correctly or you hold the clutch in at every set of lights!
Title: Re: Pushrod problem!!
Post by: BSA_54A10 on 09.04. 2012 12:38
I used to use casenit, but I have not been able to find any for a long time.
Out of curosity Trev where do you get Hardenite from now days in out risk adverse world?
Title: Re: Pushrod problem!!
Post by: RichardL on 09.04. 2012 12:49
Wilko,

Disagree,  soft ends most likely cause.  Sitting at light with clutch pulled in will not increase likelihood of mushrooming like this.  Greatest stress on ends is when clutch is activated,  not when sitting there with the pressure plate (edit: and rod) at rest. Lack of lubrication at rod end may lead to overheating and,  thus, annealing, (edit:  ...though, this is the lever end.)
 
Richard L.
Title: Re: Pushrod problem!!
Post by: mrshells on 09.04. 2012 13:17
trev its a 6 spring clutch in a 1947 rigid
Sorry about the spelling
Title: Re: Pushrod problem!!
Post by: olev on 09.04. 2012 13:40
Hardite & casenit hey? are you decrepit old b's having fun??
probably good for piles too.
cheers
Title: Re: Pushrod problem!!
Post by: chaterlea25 on 09.04. 2012 16:51
Hi Trevor,
The silver steel will harden glass hard by heating to ""cherry red"" and plunging into cold water
only redden the last 5/8in. or so
I dont know why it comes in 13 inch lengths ???? ???? ???? ????
As far as I know silver steel is referred to as "drill rod" in the USA
DO NOT USE it for spindles or in stress bearing applications

Regards
John O R
Title: Re: Pushrod problem!!
Post by: trevinoz on 09.04. 2012 22:46
Trevor,
               I've got a tin of the stuff which was "donated" to me probably 20 years ago.
Trev.
Title: Re: Pushrod problem!!
Post by: RichardL on 10.04. 2012 01:08
Disagree,  soft ends most likely cause.  Sitting at light with clutch pulled in will not increase likelihood of mushrooming like this.  Greatest stress on ends is when clutch is activated,  not when sitting there with the pressure plate (edit: and rod) at rest. Lack of lubrication at rod end may lead to overheating and,  thus, annealing, (edit:  ...though, this is the lever end.)

Oops. Sorry, Wilco, I had a brain stoppage. Of course, pressure plate is not at rest when stopped in gear, but spinning with the rest of the driven plates. Now, a little less boldly, I still believe the problem is soft ends, or soft ends brought on by too little lubrication. I have a hunch that using the ball-bearing-in-the-middle-of-the-tunnel approach probably reduces the amount of spinning friction, at least at the lever.

Richard L.  
Title: Re: Pushrod problem!!
Post by: BSA_54A10 on 10.04. 2012 11:49
Quote
Hardite & casenit hey? are you decrepit old b's having fun??
probably good for piles too.
When men were men and shopping was something that was done when needed , not a pastime or competative sport we used to make things from scratch.
There were quite a few case hardening compounds around . Like pistons ( no spand, low spand, spandex etc, etc ) case hardening compounds had self explanatory trade names ( well some we a bit play full ).
Trouble is that they are just about all based on either cyanide or arsenic two compounds that are considered "too dangerous" for Joe public to get their hands on considering that you get 25 pages of MSDA sheets if you buy hand cleaner in 25 L drums.
Title: Re: Pushrod problem!!
Post by: chaterlea25 on 10.04. 2012 20:28
Hi All,
"Case hardening" compounds are intended for use on more or less "mild" steel components
Markus will fill us in on the exact "specifications", I have a big "Casenit" tin and the instructions are for use on "mild steel" . It will only harden an outer layer of the component
Clutch pushrods need to be hard throughout (at the ends) which is why the steel of choice is "silver steel" or drillrod
HTH
John O R
Title: Re: Pushrod problem!!
Post by: olev on 11.04. 2012 09:56
To the 2 Trevs,
Apologies for the swipe about kasenit and hardite and decrepit old b's.
I should be whipped and beaten and forced to drink xxxx for thinking you were having a lend of us.
cheers.
Title: Re: Pushrod problem!!
Post by: duTch on 11.04. 2012 13:24
Nothin' wrong with xxxx,*grins* *fight* got one on the go right now, you should be made to drink it for the swipe about it!!
     *beer* 
Title: Re: Pushrod problem!!
Post by: BSA_54A10 on 12.04. 2012 22:00
Quote
"Case hardening" compounds are intended for use on more or less "mild" steel components
Markus will fill us in on the exact "specifications", I have a big "Casenit" tin and the instructions are for use on "mild steel" . It will only harden an outer layer of the component
Clutch pushrods need to be hard throughout (at the ends) which is why the steel of choice is "silver steel" or drillrod

The entire end does not need to be through hard,
If it is cased all over then the pressure plate / clutch lever will be pushing against a hard surface because the end will also be hard and will see no difference between a cased end and a fully hardened end provided that they are hardened to the same level.
The depth of hardening depends totally on how long you soak. Leave them in it for long enough and you can get through hardening of thin sections.

You can use these compounds on any grade of steel although the lower the carbon content the better it works.
the higher the carbon content the longer you need to soak in the salts and of course eventually you get to a point where the cost of holding the part at temperature is greater than the cost of using a higher strength grade of steel in the first place. Or if you are not careful and overheat end up with recrystalization and large grain growth which is not good.

The only real difference between using a cased rod and a through hardened rod is that the cased rod needs to be cased all the way back to the point where it exits the mainshaft or it might bend.

Usually you case an item that is hard to fabricate so that you can machine it while soft & easy to do then harden it latter.
Title: Re: Pushrod problem!!
Post by: pedrochapala on 13.04. 2012 04:15
i don't understand. i've had the same rod in for 16 years and nothing has happened to it.