Fluorescent Oil Additive Method

NOTE: Due to their remote location, rear engine oil leaks may be very difficult to pinpoint. This area is also very difficult to clean. Make sure to eliminate all other possibilities before removing an engine or transmission to repair a suspected leak in this area.

When diagnosing engine oil leaks, it is important that the source and location of the leak be positively identified prior to service. There are two methods of diagnosing engine oil leaks. The following procedure has been found to be very effective and requires only a minimum of equipment. Prior to using this procedure, it is important to clean the cylinder block, cylinder heads, valve covers, oil pan and flywheel housing areas with a suitable solvent to remove all traces of oil.





To perform oil leak diagnosis using Rotunda UV Leak Detector 164-R0751 or equivalent, perform the following procedure:
1. Clean engine with a suitable solvent to remove all traces of oil.
2. Drain engine oil from crankcase and refill with recommended oil, premixed with Rotunda Gas Engine Oil Dye 164-R3705 or equivalent. Use 29.6 ml (1 fluid ounce) of fluorescent additive. If oil is not premixed, fluorescent additive must be added to crankcase first.
3. Run engine for 15 minutes. Stop engine and inspect all seal and gasket areas for leaks using Rotunda UV Leak Detector Lamp (part of 164-R0751) or equivalent. A clear bright yellow or orange area will identify leak. For extremely small leaks, several hours may be required for the leak to appear.
4. If necessary, pressurize main oil gallery system to locate leaks due to improperly sealed, loose or cocked plugs. If flywheel bolts leak oil, look for sealer on threads.
5. Service all oil leaks as required.