Posted by David Sherman on Saturday, March 04, 2006 at 7:29PM :
In Reply to: Concerned-Cold diesel starting advice posted by Mark in NJ on Saturday, March 04, 2006 at 3:36PM :
It can be used safely, but be careful with it and only use just enough to start it and keep it running until it gets warm enough to fire off without it. It should only be necessary if the weather is exceptionally cold or the engine is worn.
The biggest problem is "ether lock" which happens when the ether detonates when the piston is just starting to come up, and it can't get past TDC. That's very hard on the piston and rings. If you encounter it (a definite "bang" or very loud knock coming from the engine itself, not the exhaust, let it set a while until you can crank it without any knock, and then try again using only tiny squirts of ether. WD-40 is actually almost as good as ether as a starting aid for diesels and is much easier on the engine. Take the little tube off so the spray will evaporate as much as possible. I've been told that directing a blowtorch into the intake while cranking (same principle as the "flame heater" on a military multifuel diesel) works well, but I haven't tried it.