235s started in '41 and connector types changed thru the yrs.That connector between shafts on many, not all years, has a 1/2 round loop rising above the shafts about 1.5 ". If yours has that riser loop, this post applies. The oil has to fill the shafts before the oil can reach the overflow end of that loop. The shafts and rockers are not supposed to get full line pressure. This "head/standpipe pressure" design of controlled lubrication meters the oil amount running off the rockers onto the valve tips. Often mechanics would pinch off that overflow as a band aid approach instead of removing and thoroughly cleaning the rocker asmys. Typically the increased flow overloaded the valve guides and the car would smoke after idling, especially. David