What causes the early morning romps?

[komatsuvarna]

I read the excellent sticky at the top of the page, but still didnt understand what causes this and what makes it do it. Mine does it when it gets down about 30 and lower. Sometimes it romps so hard it dies. It hasnt got cold enough to do it yet this year, but it wont be long and Id like to fix it if I could. Thanks in advance!!

[Degnol]

I rub her back, then......

[dannanw]

I too would like to know, I was origonaly told it is the GP's/Relay staying warm for a while to get the ign going. but would like to make sure.

[Dietoremain]

tired worn out injector. oil needing to be changed, maybe run 5w40 instead of 15w40

[komatsuvarna]

Originally Posted by Degnol

I rub her back, then......

LOL...thats the late night romps

Originally Posted by Dietoremain

tired worn out injector. oil needing to be changed, maybe run 5w40 instead of 15w40

Dont think its an injector, truck runs like new after 5 seconds of rompin. Oil is new, but it is 15w40.

[jesilvas]

Hang on. Holding place to type huge explanation


Ok here goes. Mine does it too. When it's cold (depends on the temp for each truck, mine is a wimp so 35-40 and down is hard), the oil is cold, so thick, so doesn't flow fast at all. Like cold molasses. But when you plug in the block heater, it does just that: heats the block. Which contains oil and coolant as well as the cylinders so everything flows nicely and combusts nicely too.
Well on each head there is a high pressure oil rail that feeds the injectors. The rail is only so big so cold oil can only flow down to the end so fast. AND it's a dead head rail, just an end, no loop. Oil enters near the front of the cylinders (#2 on the driver side) from the HPOP and gets pushed to the back (#8). Well in the firing order, #8 is RIGHT AFTER #6. So once 6 fires, it depletes what oil there is in the general area. Since the oil is cold, thick, slow, the HPOP can't push enough oil ALL THE WAY to the back of the rail to the 8 injector fast enough before that one fires, so it gets an incomplete injection. Just a normal engineering hiccup right and just has to be that way right? No.
You can either get some synthetic, an oil with a lower weight for the winter, or both. OR you can get a HPO Xover hose. Just bridges the two oil rails at the #3 to #6 cylinder area. So once #6 fires with that thing installed, you have oil coming from the HPOP AND the passenger oil rail to help replenish the rail before #8 fires. Smooths the idle, ESPECIALLY in cold starts. Makes it quieter. Keeps the RPMs very very steady. Had it on a dyno pre and post HPO Xover install. Pre install the RPMs on the comp were varying by about 50 or so. Post instal, didn't move at all. Ok, maybe 2-3.

[komatsuvarna]

Originally Posted by jesilvas

Hang on. Holding place to type huge explanation


Ok here goes. Mine does it too. When it's cold (depends on the temp for each truck, mine is a wimp so 35-40 and down is hard), the oil is cold, so thick, so doesn't flow fast at all. Like cold molasses. But when you plug in the block heater, it does just that: heats the block. Which contains oil and coolant as well as the cylinders so everything flows nicely and combusts nicely too.
Well on each head there is a high pressure oil rail that feeds the injectors. The rail is only so big so cold oil can only flow down to the end so fast. AND it's a dead head rail, just an end, no loop. Oil enters near the front of the cylinders (#2 on the driver side) from the HPOP and gets pushed to the back (#8). Well in the firing order, #8 is RIGHT AFTER #6. So once 6 fires, it depletes what oil there is in the general area. Since the oil is cold, thick, slow, the HPOP can't push enough oil ALL THE WAY to the back of the rail to the 8 injector fast enough before that one fires, so it gets an incomplete injection. Just a normal engineering hiccup right and just has to be that way right? No.
You can either get some synthetic, an oil with a lower weight for the winter, or both. OR you can get a HPO Xover hose. Just bridges the two oil rails at the #3 to #6 cylinder area. So once #6 fires with that thing installed, you have oil coming from the HPOP AND the passenger oil rail to help replenish the rail before #8 fires. Smooths the idle, ESPECIALLY in cold starts. Makes it quieter. Keeps the RPMs very very steady. Had it on a dyno pre and post HPO Xover install. Pre install the RPMs on the comp were varying by about 50 or so. Post instal, didn't move at all. Ok, maybe 2-3.

I sure appreciate the explanation. I was wondering what was going on to make it do this and you explained it great. After reading this and understanding what going on, Im sure thats why mine does it. Ive always ran 15w40 rotella, probably why I always develop this problem in the winter. Im gonna try some 5w40,unless something else would be better, and see what happens. Ive got 3 6.0 trucks that Im gonna try it in too.....they need ALOT more help then the ole 7.3 though.

[jesilvas]

Rotella 10-30 would help too.
6.0s problems are kinda different. Stiction in the injectors. The new PCM flash can help.

[justinlogue5_0]

Does Rotella make the 5w40 or ......? Safe for our motors?

[XR-2001]

jesilvas-------EXCELLENT explanation Bud !

Thanks, ,RB