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famof8
01-20-2010, 03:42 AM
Question for those who utilize "homemade" high idle poles. Does your van increase its idle speed as it warms up? I can set my idle speed between 1500-1800 RPM's just after start-up and have to go out and re-adjust a short time later when the van is racing at 2500 RPM. The things we do until our Espars are fixed. :laughing:

famof8
01-26-2010, 12:47 AM
Does anyone even use a idle pole? Bump :tongue:

Aqua Puttana
01-26-2010, 02:02 AM
Does anyone even use a idle pole? Bump :tongue:
If you're using it to just warm up the engine after long cool down periods, my question would be "Why"? I think that it is harder on the engine to idle even at "higher" unloaded RPM's than starting, letting the oil pressure build, and driving away at reasonable speed and load on the engine while it warms up to operating temperature.:2cents: FWIW.

Using one for specific purpose idling is a different scenario in my opinion. AP/vic

Altered Sprinter
01-26-2010, 02:07 AM
Here's is a Mercedes Sprinter Tip from Daimler do not :lol:idle engine for long periods on Park on an automatic as to oil not be pumped through the transmission.of which has the risk factor of bearing failing.
Richard

talkinghorse43
01-26-2010, 04:04 PM
Here's is a Mercedes Sprinter Tip from Daimler do not :lol:idle engine for long periods on Park on an automatic as to oil not be pumped through the transmission.of which has the risk factor of bearing failing.
Richard

On the face of it does not make sense since the MB high idle option has been available w/ auto tranny.

Also, since the oil pump "...is installed in the torque converter casing behind the torque converter and is driven by the drive flange of the torque converter." (from '03 service manual). And, "When the engine is running, the oil (Fig. 168) is pumped...". Also, the hydraulic flow schematic in P(ark) shows 5-40 psi in the lube circuit - the same pressure range as in any forward or reverse gear.

Can you share your source documentation for this tip?

Mike Horton
01-26-2010, 05:02 PM
We have a 02 3500 that I idled a lot over the years. We experienced catastrophic failure at 330,000 miles. I believe that between frequent 4 hr idles, pulling a trailer and many trips running wide open (80 plus MPH) contributed to wearing out the motor early. With proper care I think it may have gone 500,00 or more. No scientific proof, but common sense would dictate that if we stop long idles, slow down and take it easier when pulling the trailer we will get longer engine life.:thinking: duh! I remember looking at the rear view when leaving the rest area after a long "nap". She would blow smoke while re-entering the interstate. That should have told me all I need to know!

famof8
01-27-2010, 12:51 AM
We only idle it about 15 minutes to warm the coolant. It is our temporary fix until the booster heater can be repaired (definition of repaired... warmer weather to tear it apart.) I don't mind waiting for the van to warm, but the kids and wife sure do.

Since the van is throttle by wire, I found it interesting the idle increased so significantly once it warms to around 110 degrees. At that temperature it appears that the heater core is happy as well the engine overall. I suspect it has something to do with the combustion chamber temps and better burning the fuel, but that is just my guess.

jackbombay
01-27-2010, 06:01 AM
We only idle it about 15 minutes to warm the coolant. It is our temporary fix until the booster heater can be repaired (definition of repaired... warmer weather to tear it apart.) I don't mind waiting for the van to warm, but the kids and wife sure do.

Since the van is throttle by wire, I found it interesting the idle increased so significantly once it warms to around 110 degrees. At that temperature it appears that the heater core is happy as well the engine overall. I suspect it has something to do with the combustion chamber temps and better burning the fuel, but that is just my guess.

The pedal controls %throttle, as the oil warms up there is less internal drag in the engine so with the same amount of throttle the engine spins faster.

rlent
01-27-2010, 07:11 AM
On the face of it does not make sense since the MB high idle option has been available w/ auto tranny.
Yeah ... after having repeatedly studied the schematics, that's kinda what I was thinking ....

I have probably have easily in excess of 300 to 500 hundred hours of idle time (and almost 250K miles) .... I wonder at what point this problem will begin show itself .... :thinking:

Can you share your source documentation for this tip?
:popcorn: