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chuntag95
10-11-2002, 09:44
Okay, I will ask the stupid question, that I know someone knows the answer too. I have seen and heard to never idle a deisel more than 10 minutes. It even says something about it in the owners manual. Why? :confused: Part II: How does the high idle switch negate this (see questions one's answer) problem? I let my truck idle when cold to warm it up and sometimes it might be 15-20 minutes. :( I want to make sure I am not hurting it and would gladly add the high idle switch. smile.gif Just want to know the skinny.

More Power
10-11-2002, 13:06
We heard some interesting information last spring from an oil-field worker in Prudhoe Bay, AK. He said they have a few dozen 6.5 and Duramax trucks. All of them idle most of every day. He went on to say that they've never had a failure that could be related to extended idle times.

The cold temperatures and exclusive use of synthetic motor oil could be part of the reason why they never see an idle-time related failure, but who knows for sure?

MP

chuntag95
10-11-2002, 13:09
MP,
Thanks for the info. I use synthetic front to back, so I should be okay. Should I go ahead and install the fast idle for cold warmup?

mackin
10-11-2002, 13:16
Just the messenger...

Quote=>"When a gasoline or diesel engine idles for prolonged periods, the engine oil becomes contaminated more quickly than when the vehicle is being driven. Oil contamination is more prevalent in diesel engines because of the large amount of intake air used in the diesel combustion cycle. When idling at low rpms, such as 600 rpm, the excess air in the combustion process cools the cylinder liners, resulting in incomplete combustion and condensation of unburned fuel on the cylinder walls. These deposits are eventually drawn into the engine sump where they contaminate the engine oil and reduce its effectiveness as a lubricant.

Controlled studies demonstrate that prolonged idling typically reduces the operating life of engine oil by 75 percent, from 600 engine-hours to 150 engine-hours.

Compare the convenience of excessive idling against the cost of more frequent oil and filter changes and the amount of time your truck will be out of service while the work is being done."


=============================================
My oil will definitely darken quicker with city driving and idling......Labor day weekend I put all most 800 miles on my truck 95% highway.....When I got checked my oil still blonde.....One week of driving home routes,city,100 miles or so Black......I let my truck idle more in winter then summer normally 10/15 min in cold weather less then 5 in warm weather.....So idling is necessary,but who knows the HOW LONG is a'ok ?? Not me.....High idle would be the trick in the winter with extended idling since these trucks don't warm up fast at 600 RPM'S......I myself would like to do this at some point.....Hope I helped and didn't make it worse to decide......

MAC

[ 10-11-2002: Message edited by: mackin ]</p>

chuntag95
10-11-2002, 14:28
Mac,

Don't need the "Messenger" sign I have for work. I have worn it to a meeting or two. :D That was the info I was looking for. Something base on engineering geekology or logic. I will probably go ahead and do it as the truck finally warms up about 5 minutes before I get to work. Thank the good lord for heated seats! (I hate cold.) I finally dug out the engine heater cord when I changed my fuel filter. I just sent a sample of oil in for analysis as well and am waiting on the results. I could do that again about December and see if it looks worse.

Thanks again, :D

More Power
10-11-2002, 15:32
To expand on what mackin posted:

This provides just one more reason to perform a periodic engine oil analysis. If oil contamination does result from extended idle times (water, fuel, soot, etc.), an analysis will show that. On the other hand, if there is no (or not much) oil change, then the idle times a particular person uses won't be a problem.

Real data for your unique situation will likely provide the most reliable information.

MP

[ 10-11-2002: Message edited by: More Power ]</p>