What's new
What's new

Colchester CHIPMASTER question.

Wally318

Aluminum
Joined
Oct 11, 2016
I'm getting ready to open the headstock to address some leaks that I
beleive are O-ring related on the clutch shaft.
I would like to remove the gearbox at the same time.
Can it be done as a comlete assembly w/o draining oil and
removing the front cove I'd like to have a better look at the underside of the headstock.
Whilst looking for leaks/cracks etc.
Which bolts would let me do that? Location?
 

rklopp

Diamond
Joined
Feb 27, 2001
Location
Redwood City, CA USA
Do you have a Chipmaster aka Harrison 10AA manual? You can google for free versions on the web. The manual explains the structure. I don't see a practical way to avoid draining the gearboxes and headstock, and I am not sure avoiding draining would be a wise choice regardless. I doubt you will find a leak or crack on the bottom of the headstock unless your machine has a traumatic history.
 

Wally318

Aluminum
Joined
Oct 11, 2016
I know I'll have to drain the headstock for sure.
As for the underside of the headstock, getting a good look there
may give me clues as to where the oil is coming from.
Right now all I can deduce is that its coming from the headstock
and traveling along the bottom edges of the bed and dumping out
into the front chip tray and into the coolant resovoir.
 

swarfless

Cast Iron
Joined
Aug 31, 2005
Location
South Australia
Hi Wally, taking the headstock off the bed gains you exactly nothing except complete loss of headstock alignment. What sort of viscosity does the leaked oil have? The correct headstock oil is slightly thicker than kerosene, gearbox oil somewhat heavier. One thing you could do is examine the clutch end of the headstock with a good light & see if you can see any oil on there, & from what height. That might give you a handle on what seal/s is/are leaking. The front cover of the brake compartment is another candidate, it doesn't have a gasket, relies on a good non-hardening sealant. Re the clutch/brake shaft o-rings, I recently installed quad rings there, they're better for axial movement (resist rolling) than round section o-rings. Good luck.
 

Wally318

Aluminum
Joined
Oct 11, 2016
Hi Swarfless.
If you read the OP carefully, I was asking about removing the gearbox, not the headstock.
You can tell the leaking oil is the ISO 15 headstock oil.
Besides the gearbox oil level doesn't move.
I've been inside the headstock. The front of the clutch is sealed. As well as the rear backplate.
The clutch does leak a bit of oil off the back end of the clutch. It drops down into a baking sheet/pan.
 

swarfless

Cast Iron
Joined
Aug 31, 2005
Location
South Australia
Hi Wally, I was confused by your comment about 'complete assembly' .. I thought 'with the headstock'. Yes the gearbox comes off as a self-contained unit. It's 20+ years since I had mine off so a manual with stand you in better stead than my memory .. there ARE freebies for download on the Web. Get both the Chipmaster AND Harrison 10AA ones, the latter has more detail in the features common to both.
 

Wally318

Aluminum
Joined
Oct 11, 2016
I Have the Chipmaster manual and took a look at the Harrison manual. It indeed is a bit more detailed than the Chipmaster version. But upon closer looking noticed in both cover bolts and gearbox bolts.
So I looked at my gearbox and there are 3 larger bolts at the front that are long enough that the should allow me to remove the complete assy.
I like your suggestion re: quad rings.
I didn't know such seals/rings existed.
We have a hydraulic/industrial supplier across from where I work, they say they can get me what I need
when I get the exact dimensions.
Thanks.
 

Wally318

Aluminum
Joined
Oct 11, 2016
Well I got the gearbox off. 3 bolt and retract 2 aligment pins and she slides right off the end of the lead/feed shafts.
Well worth the effort. You can plainly see when looking up that only the outboard ring on the clutch shaft seals, but from the outside/not oil.The nexr seal inward just sits there on the shaft in open air doing nothing. Its the 2 seals on the inward end of the clutch shaft that do all the seaking as far as oil is concerned. Same goes for the back gear engagement shaft-2 seals both seal oil.
When removing all the belts/gears at the outboard end of headstock, the 1.5 inch cogged belt between the clutch and main spindle tore. It was quite old.
Will I be able to shimmy/stretch a new one over the
drive pulleys and into place?
I'm hoping I don't have to dismantle the clutch shaft?
 








 
Top