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Noisey cold...start concerns or?

Crankme69

Crankme69

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My 6.5 rattles pretty good in the am cold and does not quiet down for maybe about 1/2 mile. I have the TDCO set at -1.94. Runs super and it quiets down nicely after its warm.

The noise don't bother me any as a matter of fact I kinda like it :)

So is all that noise doing any damage? Is there a mechanical or reliability advantage to setting the TDCO back to say maybe -1.3ish for the cold winter months or?

TIA
69
 
The noise is one of the reasons the factory setting is not -1.9 on the TDCO. Once your temp gets past 160 and the PCM takes over the timing it quiets down. Mine rattles the neighborhood windows for blocks when I try to ease out on a cold morning. (( :rof: ))

It won't hurt anything as long as you don't go stomping on it right out of the gate.
Mike
 
Prolly not any colder here yet then low 40's degrees F. That is one of the reasons I am asking, not really that cold yet here.

Yea if I have time I let err run for at least a minute & then go very easy with it until she quiets down & shows some temp. I never romp on any of my motors cold.

I have kinda got my hopes up that this ole girl will be around a while longer...so that is why I'm asking.

My next thing to change is my injectors & glows...but not sure if that will be before spring.

I would back the TDCO off to -1.35 if the noise was doing any harm...at least for the winter months.
 
should hear mine at -30 for the first 10 min,you would think its gonna come apart.It don't seem to hurt it.
i got close to 20 k on it now.
 
I never start and take off, was told that's the best way to get rid of your pistons on any diesel. Have seen what happens first hand what happens, in the matter of 8 month's an acquaintance of mine took out two 6.5's by starting them and taking off. I always let it run until the temp comes up and the pistons stop slapping in the bore.
 
This is what I use to tell my wife, about just starting up and driving away,, "If I hopped on you and started going at it,, with out warming you up a tad,, you'd be pissed!" Since then she at least let's it warm up for a min or two. Gotta get those juices flowing and up to temp some. :D
 
Mine has got more noisey as I increased its air flow capabilities. Opened up the intake from an S intake and put on a cone filter it got louder, put on the big exhaut the engine itself got louder. Increased the TDCO and it got louder. So its not just the TDCO but also the modifications. Backing off the TDCO will alleive some of it and not really hurt you on performance. Setting it somewhere around -1.0.
 
figment said:
I never start and take off, was told that's the best way to get rid of your pistons on any diesel. Have seen what happens first hand what happens, in the matter of 8 month's an acquaintance of mine took out two 6.5's by starting them and taking off. I always let it run until the temp comes up and the pistons stop slapping in the bore.
Click to expand...
My wife don't baby hers either with no ill effect.

Aparently it don't seem to hurt diesels to run full bore from the get go.
Diesel generators usually fire up and run right away at operating speed. I used to run a generator(air cooled 3 cyl MWM diesel) on my old farm(no grid power) for 7 yrs,started twice daily.It logged close to 20.000 hrs on it before i sold it,still ran good.

But for the most part i warm my diesels up before going WOT
 
my dirtymax usually gets 5-10 minutes in summer and 20-30 minutes in the winter before going anywhere.it's something i've just always done.all my 6.5's have been treated the same.
 
It is just like the old school cold advance kicking out. Cold engine and air means the diesel lights later. So it goes to full advance to help the engine run by overcoming this. Rattles like crazy until 'my' DB2 cold advance switch pops in the coolant crossover. Takes about a block to warm the switch up here in our temps. This advance also warms you up faster as well.

I do other things to kill the engine aside from running it after it has oil pressure. Wouldn't go WOT due to high oil pressure, but, I am not going to sit idling fuel away. You warm up faster when under a load and moving anyway. Why let the cold idle fuel and soot get dumped in the oil any longer than it has to?
 
Well, if you are going on a long trip it may not make any difference, but for people just driving several miles somewhere and maybe doing errands it would pay to warm it up. At idle in park they use very little fuel, and you would more than likely use less fuel letting it warm up in the driveway for 5 minutes and driving 10 miles than just firing it up cold and driving 10 miles. They like to run warm and its most efficient then too, so if driving 5 miles to the store, shutting it off, and then driving another 4 miles to another store and so on, to the post office.... it will never get fully warmed up and will use more fuel.

Cold fuel has more viscocity in the IP and through injectors, potentially more restriction too, may get more pulse width codes in electronic fuel injection when driving cold

Diesels like warm fuel for better atomization and combustion efficiency.

I let mine warm up at least a minute, more if ever actually in freezing temps.
 
Damage?

Nah, not much more than it would anyways.

First time I started my 98 when the temps dropped I almost instinctively turned it off! That was at -1.91 tdco and holy crap was that sucker loud!

I've since backed it off to within factory specs for cold weather and the "bangin" goes away much sooner than when it was -1.91. Truck feels the same to the "butt dyno" as it did when advanced. Swapping out the timing is a simple process and part of my winter/summer maintenance routine now (well, a reflash is now also in there too, but that's my little secret :))

Best thing to do is start 'er up, give it a couple seconds to quiet a bit and then drive off. It'll warm up faster this way.

Why?

As we all should know, our trucks are fuel throttled. That means at idle very little fuel is being injected, so very little heat is produced.

If you want it to warm to acceptable driving temps, you have to step on the throttle to inject more fuel, to make more heat. Or, do the "hi idle mod" and click it on once started.

But you'll waste far more fuel sitting at idle waiting for it to warm (you're getting 0 MPG and diesels don't make a lot of heat at idle as mentioned above) than if you drive it down your street to warm it (getting at least "some" MPG).

There's also more to be considered than just coolant temperature when cold starting a vehicle.

Sure, the engine is coming up to temp if you sit at idle for 5-10-20 mins. But the trans doesn't build much heat, the transfer case stays dead cold, the axles are still dead cold, etc....this reduces lubrication, makes for larger clearances in components and bites you again by sucking back your fuel mileage trying to spin through a cold sump.

From a cold start/warming perspective and considering the whole rig rather than just a part of it, it's better to drive it to warm it rather than sitting still.

Just take it easy on the old girl for a couple miles until the temp gauge cracks off the peg.....;)

I'm lucky in that my street is a cul de sac and I can crawl down the road at 20-30 KPH with a smidge of throttle before I need to get on it with any real authority.

Just some stuff to think about....

:)
 
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I let it idle for a few minutes prior to takeoff.

Winter I plug it in for 1-2 hours prior to take off, and still let it run for 10-15minutes.

And as always I ease it into work.

I also let it cool down for a few minutes ALWAYS. I think of this just as important as the warm up.

Otherwise your killing it with 'hotspots', and that piping hot oil sits in the turbo.

Synthetic oil is HUGE gainer here folks. For those who havn't tried it yet, its truly night and day difference on these engines. The turbo too takes great advantage of it.
 
At idle the same compression ratio is applied so there is still a great amount of heat produced through compression of air regardless of how much fuel is being burned. This is differnt than in gassers that have half the compression ratio and limits air input. And gassers do not have fuel viscosity and gelling concern on the intial start and take off.

The trucks idle at about 8mm3/injection, so at 700rpm, 4 injections per rpm that comes out to 0.006 gallons per minute

0.006gal/min x 10min = less than the amount of fuel to get 1 mile down the road, and the next 15 miles on the road you will probably get better fuel economy so that its no loss at all.

Its not insignificant fuel use, but its pretty small, now sitting in traffic with the truck in gear and A/C on it will suck down some fuel idling, 2.5-3 times as much probably. Putting it in gear will double the fuel consumption at idle.
 
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bison said:
My wife don't baby hers either with no ill effect.

Aparently it don't seem to hurt diesels to run full bore from the get go.
Diesel generators usually fire up and run right away at operating speed. I used to run a generator(air cooled 3 cyl MWM diesel) on my old farm(no grid power) for 7 yrs,started twice daily.It logged close to 20.000 hrs on it before i sold it,still ran good.

But for the most part i warm my diesels up before going WOT
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Air cooled engines are different animals, and most are not turbo charged. All the generators I've ever layed eyes on had a block heater or a hot box that kept the coolant temp at 180 deg. The ones on the drilling and service rigs are idled for 20-30min before they flip the breaker.


sparky18 said:
my dirtymax usually gets 5-10 minutes in summer and 20-30 minutes in the winter before going anywhere.it's something i've just always done.all my 6.5's have been treated the same.
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I do the very same, I wait for when the pistons stop making all the extra clatter , that and the high oil pressure I hate fixing oil leaks which can be cause by too much oil pressure cause the relief valve may be sticking or not operational at all.
 
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