Clutch Slip or Overdrive Fault

[Borders Dolly]

My 1500HL with overdrive has just become road legal after 3 years of welding (off and on). Unfortunately it has developed a slipping clutch on its first trip after getting an MOT. I can induce slip in 2nd, 3rd and 4th, with or without overdrive. I had briefly jacked the rear up extra high for access and some oil ran out the bellhousing from the gearbox (scroll type seal) so I am assuming some oil has gotten onto the clutch friction plate during these few days when it was at a steep angle. However, I did read that the overdrive clutch can produce similar faults, although it has always worked fine during the many years driving before it sat in my garage for welding. I have checked the gearbox oil level but this made no difference.

Can I assume that my overdrive clutch is still fine and the fault is probably oil on the clutch plate? Is there any checks I need to make before I pull the engine and gearbox out for a look? Although I like my dolly I don't want to have to take the engine out twice if the overdrive is toast.
Thanks

[Carledo]

Definitely sounds more like the main clutch than the O/D clutch, though oil on the plate will often cause an accompanying judder. Don't forget to top up the gearbox if you've lost that much!

Steve

[tony g]

Yes its the normal clutch. If its the O/D it wont slip when engaged as it doesnt drive through the one way clutch (in the O/D). Front seal in the box leaking into the bell

Tony

[Borders Dolly]

I took the engine and gearbox out and the clutch was contaminated with oil. The new clutch is installed and it is driving normally and I went to the Selkirk car show on Sunday with no problems.
Once I took the started motor off and realised the inside of the bellhousing was oily I knew I had found the cause. In hindsight taking the starter off for a look would have confirmed the fault earlier.
Thanks for your help.