M18 Universal Diesel Hard to Start?

[SolNola]

Originally Posted by MarkSF

Try checking the actual voltage at the glow plugs while pressing the button. It shouldn't drop too much from 12.7V. Maybe 1V?


When my voltage was passing through the unnecessary 12ft of dodgy undersized wire and two crap quality trailer plugs, it was dropping a lot more than that.

Thanks.

Another question: how much failed cranking could it take to flood the engine with seawater? I wasn't considering that last weekend...

[Lepke]

If the engine started once, you probably don't have a fuel problem. You could have low compression. Sometimes when an engine sits for a long time, the rings contract. They don't fully expand again until the engine reaches operating temperature. I assume in New Orleans it is warm. A diesel needs to compress the air until it's temperature is above 500°F for ignition to happen. (Air gets hotter as it compresses) In cold weather heat is usually required in the form of glow plugs, block heater, or pan heater. In a pinch, a hair dryer pointed into the intake will usually work. By starting with warm air or heated block you don't need as much compression to reach ignition temp.
You can use ether, but a small engine only needs a whiff. Don't ever run an engine on ether. Too much ether creates much higher pressure and can crack rings. Then you need ether all the time.

[FPNC]

The engine started and ran once and pretty quickly, considering it had not been started in awhile and you had not figured out the glow plugs. So the engine is probably fine. You need to make sure you are getting proper fuel without air or restriction to the engine. Try changing all fuel filters, bleed and try again. If you want to truly isolate the problem, try feeding clean fuel to the engine from a 1 gallon jug. If the engine runs on the jug, you have an off engine fuel supply problem. Never power the glow plugs more than 10 seconds. If you keep that up you will need new glow plugs. If your volt meter drops when the glow plugs switch is activated, that is a good sign they are working. When things are right, in NOLA you should not even require glow plugs to start the engine. Do not use ether.

[rpeebles]

Off topic but can someone help me choose a prop for my M18? Powering a Chesapeake 32 full keel displacement around 11500 lbs. Thanks.

[capt jgw]

Originally Posted by FPNC

The engine started and ran once and pretty quickly, considering it had not been started in awhile and you had not figured out the glow plugs. So the engine is probably fine. You need to make sure you are getting proper fuel without air or restriction to the engine. Try changing all fuel filters, bleed and try again. If you want to truly isolate the problem, try feeding clean fuel to the engine from a 1 gallon jug. If the engine runs on the jug, you have an off engine fuel supply problem. Never power the glow plugs more than 10 seconds. If you keep that up you will need new glow plugs. If your volt meter drops when the glow plugs switch is activated, that is a good sign they are working. When things are right, in NOLA you should not even require glow plugs to start the engine. Do not use ether.

Never use ether, but you can try WD-40. It's mostly kerosene which is very similar to diesel fuel. Spray into the intake while cranking. If it runs on WD-40, it's not a compression problem.