Wondering about glow plugs on 273

[Stumpshot]

My 2009 273 is getting hard to start. It starts after lots of cranking and dumps a ton of black exhaust when it fires up. We seldom have winter temps below 45 degrees here so it's probably not cold related. The preheater light comes on and off like normal and I cycle as many as 3 times before it finally fires up.
Where should I start to check this out? I replaced the preheater 5 or 6 years ago but I think the light didn't come on when that unit failed. Got about 300 hours on this rig and I'm wondering about replacing glowplugs. Don't have a dealer within a couple hundred miles so I'll do this stuff myself. Any ideas about this problem or how to analyze it is appreciated.
Thanks for your thoughts.

 

[Bud Soda]

Check for voltage at the glow plugs after you turn them on. Sounds like all your plugs are bad. You can check them with an ohm meter. My 273 has always started with one cycle of the plugs but I have never tried to crank it under about 40f I have over 700 hours and had to replace the battery one time. A weak battery will make it hard to start also. If the plugs are good could be the relay.

GLOW PLUG Part #
Mitsubishi 32A66-03100 - Glow Plug | Forklift Parts, Sweeper/Scrubber Parts, Aerial Lift Parts and More at TruPar.com

http://bestfarmparts.com/century-glow-plug-2035-replaces-32a66-03100-p-1902.html

This should be the same Amazon.com: NGK (6528) Y114T Glow Plug, Pack of 1: Automotive

 

[pmsmechanic]

You can also check glow plugs with a test light. Disconnect the glow plugs from the wiring harness and each other. Connect the test light to 12 volts and touch the terminal of the glow plug. If the test light lights up then the glow plug is working. If several glow pugs aren't functional then I usually just replace them all and keep the used ones as spares.

 

[Stumpshot]

Thanks for the info! I got a classic case of typing before thinking again. Forgot to mention that, once started, the rig fires right up and will do fine the rest of the day. Only after sitting for several days does this problem occur. I will check the things suggested.
Thanks again!