Clutch pressure plate very close to gearbox

[JohnDough]

I've got a 1275 motor and will be using a ribcase gearbox. I'm still using a spring type clutch. It's fairly big and bolts on very close to the edge of the flyweel.

lsat night I did a trailfit of the gearbox and noticed through the top inspection hole that the clutch is very close to the gearbox.

The engine did turn freely but I thought I heard scraping noises, the inside of teh gearbox was not scraped but it looks like the pressure plate might have a scuff mark.

I would like to get the car going and don't want to change the pressure plate as it was balanced with the fywheel.

Is this normal?
Do I need to clean/grind the gearbox a bit?
Do I have the wong clutch?

Thanks.

 

[JerryB]

."""""" I'm still using a spring type clutch""""

maybe I didn't read right but the earlier B&B 6 spring pressure plate won't screw onto a 1275 flywheel.


"""""""that the clutch is very close to the gearbox.""""""

the most rearward point on the cluch assembly might be the pressure plate pad that mates with the t.o. bearing pad. Just possibly tho the p.p. cover might have some interference right in back the spring pockets in the cover.

How you got an early p.p. to screw on a 6 1/2" dia pp pattern on the flywheel I dont know.


""""""on't want to change the pressure plate as it was balanced with the fywheel.""""""

And the common practice is to zero balance the flywheel and then the assembly. You can change the p.p.

 

[JohnDough]

Thanks JerryB.

Looks like the PO owner had the flywheel drilled and tapped to take the spring clutch, at the moment the engine is compiled of the most interesting set of parts you could imagine.

 

[JerryB]

John.....

so we got that out of the way....

use the correct 1275 6.5" diafram pp and matching disc and the 1275 throw out bearing.

That will all clear inside the ribcase bellhousing.

The throwout fork when pulled back by hand and the to bearing against the pp should be just forward of perendicular with the crankshaft center line.

You might have to adjust the pushrod (longer/shorter) if you are using the earlier pushrod (slave cyl to to fork) or get one from a 1275.