When to switch to synthetic? Recent rebuild.

[Smokey Eddy]

I have roughly 300km on my rebuild and i've been running 15w40 conventional to seat the rings (plus i have like a 5 gallon drum of the stuff)

I finally insured it and its my DD so im just wondering when you fella's think it would be wise to switch to synthetic? I don't want to run conventional very long because i have ZERO boost control so sometimes i'll hit 20psi.
I'd feel much safer with nice synthetic in there but i don't want to fubar my new rings up.

Is there something i should look for?

i know oil consumption is one thing but i was thinking there might be something more obvious?

The starting has DRASTICALLY improved since driving it 200km. I no longer need to plug it in (but i do anyways on morning starts) and it doesn't burn 1/4 as white as it used to.

Thanks Fellas.
Ed.

[arb]

I only wait until the rings are completely seated - oil consumption is the only measure of this I use... When there is no more, go one more oil change - 4,500 km. then switch and watch your mpg go up and your engine will look inside just as it does today in another 160,000 km !

Lately I've been using Meijer's 100% synthetic oil. I'm not sure who makes it for them, but it is 2/3 the price of Mobil 1. In other words, about $4 a quart.
They don't show their auto section online for some reason... http://www.meijer.com/

[saurkraut]

I think I did around 10K miles on dino oil befor switching to synthetic on my 1.6TD build.  It was a re-bore; new pistons, rings, and all bearings (counter shaft too)

I drive it like I stole it.  Loots of boost, and lots of soot. It burns no oil until I get over 2,500 miles on the oil, then it starts using a little.  I dump it at 3,000.  I suspect my state of tune and driving technique puts allot of soot in the oil.  At 2,500 miles it has "all it can stands, and it can't stands no more".

Yah it costs more, but it protects your investment allot better.

[jtanguay]

I think I did around 10K miles on dino oil befor switching to synthetic on my 1.6TD build.  It was a re-bore; new pistons, rings, and all bearings (counter shaft too)

I drive it like I stole it.  Loots of boost, and lots of soot. It burns no oil until I get over 2,500 miles on the oil, then it starts using a little.  I dump it at 3,000.  I suspect my state of tune and driving technique puts allot of soot in the oil.  At 2,500 miles it has "all it can stands, and it can't stands no more".

Yah it costs more, but it protects your investment allot better.

you should run some oil analysis on your used oil to see how its breaking down.  if you're actually shearing the oil to the point of viscosity change, then maybe you should be using a better oil.  if you use a better oil you could use a centrifuge to take out all the contaminants and bring the oil back to normal and then pour it back into the car  :wink: that would save a ton of money  

[saurkraut]

I'm running Mobil Delvac 1, or what ever they call it under other lables they put on it like Mobil Diesel Truck Synthetic 5W40.

Like I said it uses no oil untill 2,500 miles.  Over the next 500 miles, it loses some where between 1/4th and 1/2 quart.  I check my oil every time I fuel it up and this cycle repeats every time.  I suspect its loaded with soot by the time it gets to 2.5K miles.  The oil actually stays clean for a while (maybe 1 tank of fuel) after I change it.  So its getting all the soot out when I drain it.

I guess I could pay for an analysis.  But I don't have a problem with dumping the stuff at 3K miles.  My compression is excellent, the motor runs great under what some would concider abusive conditions, and I'd rather pay more for oil, then change my driving habbits or do another full rebuild prematurly.

[jtanguay]

I'm running Mobil Delvac 1, or what ever they call it under other lables they put on it like Mobil Diesel Truck Synthetic 5W40.

Like I said it uses no oil untill 2,500 miles.  Over the next 500 miles, it loses some where between 1/4th and 1/2 quart.  I check my oil every time I fuel it up and this cycle repeats every time.  I suspect its loaded with soot by the time it gets to 2.5K miles.  The oil actually stays clean for a while (maybe 1 tank of fuel) after I change it.  So its getting all the soot out when I drain it.

I guess I could pay for an analysis.  But I don't have a problem with dumping the stuff at 3K miles.  My compression is excellent, the motor runs great under what some would concider abusive conditions, and I'd rather pay more for oil, then change my driving habbits or do another full rebuild prematurly.

well if oil is cheap and you don't mind getting your hands dirty  :wink: i know someone who doesn't change his oil for around 25,000km or so or every year.  those stupid power steering lines always get in the way of the oil filter, and the oil always leaks down the side of the filter when i remove it  :roll:

so far with my FS-2500 bypass filter the oil looks pretty good for 500km.  its just a little darker, definitely not as dark as it would normally be at this point.  i'll probably take an oil sample at 1000km and send it in to see how good its doing.  it'll pay for itself after about 2-3 years or so.  and i expect that the engine will last a really long time with less exposure to high soot levels.