CRB to rub or not? & gearbox rear seal...

[timb2117]

Good people I have read and re read the posts, 6 speed caterham gearbox, 2005 to 1800 K engine....

I get the pros and cons but do I leave the new Clutch Release Bearing lightly engaged at all times on the tines of the clutch release plate, or (easy fix) fit spring/ stop point to keep it just clear and not in permanent contact? Million dollar Q?

Then part B, does anyone know the exact rubber seal size/ designation for the rear end seal on the same box (I know CC have it but would like to source locally) - on account of some numpty fitting the new one the wrong way around.....shame on me....- it was a big day though :) thanks a million, Tim

[SLR No.77]

Re. the CRB, I've always setup the clutch with clearance and not had a CRB failure in over 20 years if Seven ownership. I'm aware some people preload the bearing though.  
I do tend re-use the old bearing rather than replacing though, I'm sure some failures are due to poor quality bearings and if the old bearing is good I keep it.

Stu.

[Wrightpayne]

The rear seal is the same as the type 9 ford gearbox.

Re CRB preload - have you found / read John Vine's article on the matter? He advocates a second spring to add more pre-load on the bearing.

[revilla]

... or (easy fix) fit spring/ stop point to keep it just clear and not in permanent contact?

Is it really that simple in a Caterham though?

Even in my SV there's nowhere to put my left foot when not operating the clutch; it ends up resting lightly on the pedal, which must take out any clearance and leave the CRB in light contact. In which case, it will spin all the time and if it slips against the pressure plate will wear and get hoy, hence the requirement for more preload as per John's article.

[timb2117]

Yup I did read Johns article but just wanted some clarification, think I will leave it lightly touching on the spring pressure and go from there. Sadly when I say Ford type 9 in Australia people go gooky eyed "what you mean its not an auto?/ Sierra what?" :)

[John Vine]

Re my Guide, it's not just my advice to have a pre-load but the advice of the CRB manufacturers (INA for the original Ford item and SKF for CC's alternative).  On top of that, Ford implemented an automatic cable-tensioning mechanism in the Sierra to maintain the necessary pre-load.

These CRBs are designed to run at engine speed all the time.  The idea is to avoid the sudden acceleration that would be involved when a stationary CRB hits the rotating diaphragm springs.

...think I will leave it lightly touching on the spring pressure...

Do you mean the existing spring between the pedal and the back of the pedal box?  If so, that spring is too feeble to apply the necessary pre-load.  As far as I can tell, its sole purpose is to prevent the clutch cable from escaping the slot in the clutch fork.

JV 

 

[John Vine]

Re the rear oil seal...

According to my records, this is Ford P/N 80ET-7052-AA, FINIS code 1590441.  Can a local Ford dealer help you out?

JV

[timb2117]

Hi John many many thanks I will revisit the spring, which was non existent when I bought the car, - it was actually running a hydraulic pedal mechanism that was a bit problematic,

I replaced with cable on advice here and fitted a spring arrangement as the pedal was swiningin' in the wind - just now with putting in a  brand new clutch and CRB etc I wanted to ensure longevity, certainly at tickover the CRB is held onto the diaphragm springs, but it will be easy to improve this pressure as the spring is crudely adjustable.

Thanks again, great resource of information.