706 Transmission Oil Leven

Bought an old 706 gasser and I'm getting it ready to make hay. The dipstick for the transmission is in front of the seat like my 656 Hydro and looks the same however it doesn't say anything on the stick about how to read the oil level. The 656 says to read it at 1200 RPM with the oil warm. Do I read the 706 the same way or with the engine off. Also, it 'diesels' on after you turn off the engine sometimes. Is the timing or something off? I'm using 89 octane ethanol blend in it. Thanks.

There is no ignition timing when you shut the tractor off. Just a hot chunk of metal rotating and sucking in fuel. Therefore, ignition timing has zero effect on your dieseling problem.

Make sure your throttle is closed before you kill the tractor and that the idle speed is set nice and low.

Allan

The trans oil level is read with the engine OFF.

Engine run on is caused from an engine running extremely hot so if your timing is advanced to much it could cause it, and from foreign material in the cylinder head (carbon) being hot enough to cause ignition.

From Wiki:

This condition can occur for a multitude of reasons:

Built-up carbon in the ignition chamber can glow red after the engine is off, providing a mechanism for sparking unburnt fuel. Such a thing can happen when the engine runs very rich, depositing unspent fuel and particles on the pistons and valves. Similarly, non-smooth metal regions within the piston chamber can cause this same problem, since they can glow red. It has also been suggested that an improperly rated spark plug can retain heat and cause the same problem.

A carburetor that does not close entirely can contribute to running once the engine is off, since the extra fuel and oxygen mixture can combust easily in the warm piston chamber. Similarly, hot vaporized oil gases from the engine crankcase can provide ample fuel for dieseling.

Incorrect timing.

An engine that runs too hot or too lean may produce an environment conducive to allowing unspent fuel to combust.

An idle speed that is too fast can leave the engine with too much angular momentum upon shutdown, raising the chances that the engine can turnover and combust more fuel and lock itself into a cycle of continuous running.

"Engine run on is caused from an engine running extremely hot"

That is total fabrication.

Also, please explain how advanced engine timing causes an engine to run hot? That just simply is not so.

Retarded timing can make a loaded engine run warm, but when temperatures at the exhaust valve stem are running between 1200 to 1500° anyway, an increase of 100 or even 200° of higher water temp isn't gonna make much of a difference.

Again, kill the fuel and you've solved the dieseling problem.

Allan

The 656 dip stick is for a hydrostatic tractor. The oil level in them must be checked with the engine running. All others are checked with engine off.

The dieseling is caused but a defective or missing shut off solenoid on the carburetor. The solenoid shut off all fuel to the main jet when the ignition is off to keep any fuel from being drawn into the engine while the engine is still turning over.

If you're talking about the hydrualic, I think the full mark on mine is about 1.5" from the end of the dipstick. But I run it about 2 gallons over full anyway, I have a too-big Westendorf loader on it and need the capacity. Lots of 706's are run with an extra gallon or two to prevent sucking air when the MCV seals get leaky.

I'll back it up a bit for you:

Timing advance is required because it takes time to burn the air-fuel mixture. Igniting the mixture just before the piston reaches TDC will allow the mixture to fully burn soon after the piston reaches TDC. If the air-fuel mixture is ignited at the correct time, maximum pressure in the cylinder will occur sometime after the piston reaches TDC allowing the ignited mixture to push the piston down the cylinder with the greatest force. Ideally, the time at which the mixture should be fully burnt is about 20 degrees ATDC. This will utilize the engine's power producing potential. If the ignition spark occurs at a position that is too advanced relative to piston position, the rapidly expanding air-fuel mixture can actually push against the piston while it is still moving up, causing knocking (pinging) and possible engine damage. Compressing the rapidly expanding ignited fuel-air mixture also causes excessive heat.

Any other questions?