C-12 Stumbling on Cold Start

[Dick Simonis]

I noticed that the 505 C-12 in the Marguis we're looking at starts a bit harder than mine and stumbles a bit for just a few seconds when started in cool weather......mid 40's or so.

The hard starting might just be the coach batteries being week as using the parallel switch helps.  The rough running is different from mine which starts right up to a smooth idle at all temps.  Granted quite a bit of white smoke at start-up on both but that seems normal and goes away withing seconds.

Any reason why the 505 might stumble a bit on cold start that I should of concern about.  I might push the issue and have the coach taken to Cat as part of the PDI even if on my nickel.

Thanks
Dick

[Michael Marcocchio]

Hello some if not all Diesel don't like starting in the cold. Remember diesels are compression fired which means they need heat in the combustion chamber to fire the fuel vapour.Most smaller diesels have glow plugs or air heaters to help with cold starting the bigger one usually have coolant block heaters my has the aqua heater to help with cold startingThe rough running just means the engine need some heat to warm up some start better then others all depends on hrs on the engine wear of the injectors and piston and rings.Try to prewarm your engine before starting and you should have no further problems if it a little warm. Hope this helps I wouldn't worry to much about it.

[Gerald Farris]

Dick,
The prescreener (plastic cylinder/sight glass) on the Racor primary filter/water separator has a tendency to leak small amounts of air into the fuel system. I would have it checked. Other than that, like the previous response stated, it is probably a combination of old chassis batteries and low temperatures.

Gerald

[Glenn Perkins]

Our 99 Marquis has always (167K miles) stumbled with a lot of blue smoke briefly when the temperature is much below 50 degrees.  Using the hurricane and engine preheat helps but for me, it is just a FOL  In my experience, weak starting batteries exhibit a different symptom ... often requiring use of the cross over with house batteries.  On ours, weak starting batteries could often be traced to a blown fuse on our Magnum Echo Charger (installed after 2 failures within a year with the original Xantrax unit).

My 3 cents.