Roll Starting Bad?

[sandcruiser]

Now that my driveway is *really* steep, I've taken to backing in and roll-starting the truck in the morning.

Today as I was driving off I got to wondering if there is any reason that this isn't good... it runs just a tad rougher this way for 30 seconds as usually when I start it I let it idle for about 30 seconds to get the oil pressure up.

For the record, I do still glow it before rolling off. And I start in 3rd, then shift down into 2nd to drive (bumpy road).

 

[Tapage]

I' don't have any reazon to thought are really " bad " but for sure are not the best way .. I'm pretty touchy with cold starts .. more wear on our engines occurs at this time .. also thinking your idea of stay idling for 30 segs are so good .. but I leave idling my both cruiser for at least 1 or 2 min before move it .. and don't go over 2000 rpm ( 1HD-T ) and 1600 rpm ( 2H ) until it take normal operative temp.

I'm pretty sure that your engine and your entire cruiser continue working perfect with this " method " how long .. ? I'm not sure ..

 

[brownbear]

As long as when the engine comes online it isn't rev'd to high....thats bad on the cold engine. As the head isn't hot enough and the extra force on it from bad detonation could cause problems.

other than that, if you can see it go to max of 1000 rpms and then idle for 30 seconds to get the head up to a consistent heating, then your ok to go.

also note: no diesel should be worked hard or put under load till it is up to temp. but you can start to drive softly after about 30 seconds to bring it up to temp.

the missing(knocking) feel or sound you get after start up is bad detonation or failure to detonate at the right time, due to not enought heat on the head/cylinders.

most diesel idle smoothy after about 15 seconds, but sometimes you feel slight missing detonation once you start to drive, or loud detonation, this is due to not enough heat built up yet to add in combustion. this is when you drive it easy and don't go blasting off.

IMOP

 

[brownbear]

oh I should add, a rolling start warm should not cause any problems, again as long as it isn't over rev'd..

 

[R2HKS]

If its from a cold start why don't you crank the engine over for a while before you hit the glow plugs. Say 10 secs or less cranking to get the oil pressure up then glow then roll start. If you got an oil pressure gauge you should see the pressure come up, when its a 20psi your good to go.

I quite often roll start and that's the method I always used from a cold start.

 

[crushers]

um, why not start using th starter?
what are you saving by roll starting?

 

[Diesel Dude]

I would guess that since the bearings require a film of oil which is not entirly there when you first start it, great care must be taken to make sure the engine is seeing the leats amount of load possible until this film is present. There for cold roll starting is probably not ideal.

 

[brownbear]

I worry about the head getting too much pressure cold.. with bad detonation. Bearings will get oil after it runs anyhow.

there is always a moment when starting an engine that the oil isn't where it should be. rolling or using the starter.

 

[Diesel Dude]

I agree there is always a moment however the less load that you can apply to your bearings the better, I.e using the starter rather than the load of the truck.

 

[Tapage]

I thought the main problem with roling to start is the aceleration at the exact start moment ..

 

[sandcruiser]

interesting

to clarify: by "cold" start, I am referring to ambient air temperature of approximately 85 degrees F (30 * C). So... not really "cold"

As for why... just cuz its there. I'm headed down the steep drive either way.

But this is exactly why I thought to ask- seems that the consensus is that it *does* matter and that traditional starting is better than rollstarting. So I'll just go back to 'normal' starting and call it a day.

Thanks everyone!