Questions: warm-up/cool-down phase and oil interval

[pleopard]

Hi again everyone.  Pardon me if any of these questions have already been asked.  I searched and couldn't find specifics.

#1  Is it adviseable to let the 1.6 TD warm up for a few minutes before driving off in the morning?  The owners manual says to just drive off right away as it increases the rate of warm-up, which makes sense, but the manual is mainly oriented towards gasoline Jetta owners. I notice that the engine takes an exceedingly long time to reach what I might call operating temperature while I'm driving.  Generally, after driving at highway speeds, I let the engine idle for a minute or two to allow the turbo to cool a bit before killing the power/oil.

#2  What was the factory oil change interval on this car?  It's a 92.  I just recently switched to Rotella T 5w40 synthetic.  Should I continue changing every 5000km or push it further?

Thanks guy and girls (?)

[RabbitJockey]

i pretty much agree with the owners manual, i just drive my car right away, in the cold i give it a minute, which i think makes little difference, but it makes the cabin a little more comfortable haha.  but on my car as far as warm up, i always take it easy till the needle makes it to the middle of the temperature gauge.  and cool down i do the same thing as you, accept when i drive very hard, then i will go for a little drive through a development or something and then let it sit for a minute before i shut it off.

[pleopard]

Thanks for the response Trev.

[Black Smokin' Diesel]

Exactly like Trev0rbr said, drive it right away. If it's really cold (below freezing temps) I usually wait one minute for the idle to settle down and drive off.

5000km is a good interval, especially for a TD.

[HP]

Synthetic oil, man...  :roll:   That should do at least 10.000Kms, no?

[745 turbogreasel]

Coming home, I pretty much idle the last mile, and my EGT is ~350, allowing for a short cooldown period.  When I park at a mountaintop, much idling is required to reach this level.

[pleopard]

Well, I have no idea what my EGT is as I don't have any extra guages installed.  How could I go about installing guages?  Where do I look for info?

Regarding oil changes with synthetic, is the consensus that I can and should go beyond 5000km before a change?

Thanks.

[745 turbogreasel]

Best is to drill a hole for the sending unit upstream of the turbo.  Do not splice the sender wire.
Make sure ground connection is very good.

Very generaly, you will see a 100F rise for each pound of boost  on a stock IDI, and it will take about a minute at idle to drop 200*, although engine braking speeds this considerably.
So 30 seconds or less after idling around the neighborhood, or 4-5 minutes afer coming off the track

You oil change interval will probably be most influenced by blowby...There are oil testing services you can send samples to for analysis, it costs $25-35US.

[pleopard]

Since I have yet to get into any modifying and my car is entirely stock, I'll just hold off on the EGT guage for now, but it's interesting and in the future I'll give it a shot.

Thanks for the oil change tip though.  I'd guess my blowby is fairly low considering the engine was fully rebuilt at 200,000km and then sadly the head had to be rebuilt again just two weeks ago.  My poor poor car!  It's not burning oil at all, no smoke (injection pump was also rebuilt) and she runs quite smooth...  

Thanks

[935racer]

Everybody's definition of a rebuild is different, unfortunately, some peoples idea of a complete rebuild it rings and bearings :shock:

As for warm up and cool down, I always let my diesel engines idle for a minute before I drive them, more if its cold out. And let them cool down for at least 20 seconds idling, or a couple minutes if she is cooking hot from a long highway run.