JD 630 gasoline to oil transfer

Jeff

It has a side brass like looking T fitting where oil lines enter it, ones up from an oil tap on the tractor and another goes up to the oil pressure gauge. If it or the lines are removed ONLY OIL SHOULD BE PRESENT THERE but if gas runs out, the internal rubber diaphrams are leaky and need replaced. You can still buy the rubber diaphrams from John Deere and I always clean the seating surfaces and change the lil o ring/gasket on the vertical shut off plunger when Im in there.

If you have a clear glass sediment bowl (or better yet remove it to observe the operation) and the carbs drain is open or its inlet line removed or loosened. You ought to be able to loosen the knurled nut on top center of the assembly and push down on the threads and see the lil plunger go down (open), but when its raised, it ought to seal off gas from entering the bowl if its NOT a leaker. How it works is when theres no oil pressure in the lines to push down on the diaphram, the vertical shut off plunger (is up) shuts off gas to the carb. However, as noted above, if it has a leak, gas can get into the oil then via those oil lines. If you removed the lines and/or that T and if gas (not oil) runs or drips out, its a leaky internal diapram.

Other ways gas can get in the oil is if BOTH the shut of assembly didnt work (maybe the vertical shut off plunger dont rise or seal tight, surfaces need cleaned and/or needs new o ring/gasket) PLUS the carbs float and/or needle valve n seat fail allowing gas to overflow the bowl and drain into the engine. If the tractors sitting and you drain the carb and leave it open to observe, NO MORE GAS should flow into the carb if the shut of asembly is working properly.

Take a look and let us know what you find, get that gas out of the oil for sure before you hram something.

God Bless

John T

Or if that is no longer installed on the tractor and the gas has not been shutoff manually, the needle and seat in the carburetor is leaking and the gas is leaking through the carburetor into the combustion chamber into the crank case.

Both problems could be happening at the same time as well.

I will check the automatic diaphram.

I know my dad does not shut off the fuel valve at the gascolator after use.

The tractor is generally in good shape, but needs a little TLC. I plan on going through the tractor this winter. I think a carb rebuild would be a good idea in any case.

Thanks!!!

Jeff