Going to try to start a JD 70 diesel that has not ran for 5 years

On the pony engine, I would pull the plugs and squirt WD-40 into the cylinders and crank the engine w/o the plugs in place. Put in new Champion J8C plugs, add fresh gas with a little bit of Marvel Mystery Oil to the pony engine tank, new oil in the crankcase and try to get the pony engine so it will start easy and go up to high rpm w/o problems. Once the pony engine is in good running condition, then you can focus on the main diesel engine.

After filling the radiator with clear water,I would add diesel fuel to the crankcase (~2 gallons) and then "motor" the diesel engine with the pony engine in the decompression, throttle all the way back(injection pumps off) mode for several minutes. Drain the crankcase, change the oil filter and fill with new oil. Next, bleed the fuel filters and the fuel rail to make sure the pumps will have fuel when needed. Start the pony engine, motor the diesel engine for 1- 2 minutes (make sure you have oil pressure) w/o compression, bring the rpms's up on the pony engine and then give the engine full compression. It should start after only a few revolutions. I'd then run the engine for a while to bring it up to temperature, shut the engine off and drain the coolant system to check for any signs of diesel fuel (engine flush) or crankcase oil. If you have oil in the coolant then it's time to determine the source ( most likely head gasket on the pony engine, head gasket on the main engine, injection tubes or a crack in a casting (head). Next step..get the check book ready.

I have been through his process with several 70 diesels and if you need help, send me an e-mail. Good luck!!

The black specs of oil are coming probably coming out of the muffler. If you wipe your finger in there, it is probably slimy. This generally indicates poor rings or pitted cylinders. Been there done that (re-bore and pistons). Unburnt fuel from leaky injector tips could also be a contributing factor.

The slime in the coolant could be there as a result of a leaky headgasket at the main engine or even the pony. The pony can get water in it's oil and vice versa through a bad water pump shaft or seals. The shaft is NLA from Deere, but Greg STevens has them. If one seal fails, oil in the water, if the other fails water in the oil. Ponies are $ to repair (been there done that), so be sure you have quality clean oil and pressure in that pony before you fire it up for an extended period. CLean out the oil return holes in both heads....they are very small and will gook shut easily). After sitting for a time, they tend to leak at the rear main seal, which means pulling the pony (not really a bad job).

If the pony is ready to be cranked and ran, I would drain the diesel engine crankcase, and re-fill with diesel fuel and a new filter, and then motor the main engine for sometime to wash everything out. This will do no harm, and it called out in the book as a matter of regular oil changes (in fact they run the engine for 5 minutes....really cleans things up). Then you can re-filter and re-fill and know that you have clean oil. If anything shows up then, you'll know it when it came. It's also easier to tell diesel fuel from water at that point.

I been into just about every area of both engines in the past year. They can be expensive to repair the right way.

Frank-in-Tallahassee
70D // 855

There aren't any plugs you can remove to gain access to the cylinders. You could remove the injectors for access, or remove the intake a squirt some oil in there, hoping it run down into the cylinders through the valves.

I personally wouldn't worry about it. If you establish that the main engine has oil pressure, I'd just motor it for a nice long time. That will get plenty of oil up to the cylinders and wrist pins.

Frank