+1 on the tool

 

The one time I drained the turbos, my car made a weird
"IMS" kind of noise after the oil change that was never there before. I was told that the sound was the turbos "cavitating". Which is what propellers underwater in submarines do. Who knows. I won't drain turbos again.

 

Yes, cavitation is when the propeller turns fast enough that air bubbles form in the water. It sounds like you were told there was air in your turbo cooling system - probably not good.

 

research i did showed thats why the fuel pump fuse is pulled and car ran until it shuts off. after the oil refill turning the car over the car until fuel pressure starts to build. this allows the turbos to get the lubrication they need without running full time

 

Thanks for all the tips guys,,,this forum never lets me down!


Engine guy Thank your for reassurance, I do my oil changes on my X5 4.8 and my Motorbike so I will be brave and im sure i can do a better job in the end... Good to know theres some Calgary guys on here! where in the city are you? PM me we should link up in the spring or if I struggle I may need to bribe you to assist with Beers lol

Thanks you JSBEAR for posting the links

Pumptech and Steve Theadore - Yes sounds like my motorbike pan wont be Large enough!

Thank you Constaga I am just going to go to dealership and buy the wrench no messin around!


32Krazey Thanks for the advice Im nervous to pull fuse Ill see when i get to that step but definatley ill flush a liter through to clear out bad oil..and Thanks for tips on 2 wrenches!

 

can you imagine hearing what sounded like an ims rattle when before there was none.. AFTER draining/refilling the oil? i learned that lesson.

sorry, it's must be me.. but i'm not clear on what you meant at all. are you saying you pull the fuel pump fuse to drain the turbo's i don't think that's what you mean either lol but no big deal. i'm not draining tablespoons of oil any more! so it's moot.

 

02996ttx5, I think what 32 Krazy means is he pulls the fuel pump fuse to allow the engine to run dry on gas. Once the oil is changed, a fuel-less system allows the engine to spin without turning over in order to build oil pressure on a cranking engine without having it fire. Once oil pressure has built up, the fuse is replaced and the engine started normally.

 

Well point 1... Running the car out of fuel creates a lean condition that is hard on an engine even at idle speeds. I was going to explain why but I won't as it is to much to type for my painfully slow speed.

Point 2... Turning the car over until pressure starts to build usually runs things dry for a longer period then a partially dry start up and for other reason which I won't type that act too can be harder on an engine.

I say don't worry about the small amount of oil in a turbo; do not drain it and then change your oil more frequently so the oil anywhere in your engine will not be past its service life. But plainly put running a high quality synthetic oil and staying within the manuals service interval is more than adequate.

Best bet if you really want to care for your cars engine then install an electric pre-oiler system.

 

im interested to know your thoughts about lean condition at idle. it only takes maybe a minute to run the car to a stall. as for startup to build pressure , im adding qt thru the filter housing to lube the top end of the engine. and let it drain down. this helps (to me) more than just firing the engine and letting it build as i can control the amount of time the engine turns over. small bursts until pressure builds. when i finally fire the engine theres no death rattle and the car purrs smoothly.

im sure theres many ways to do this but this is my preferred way. i wholeheartedly agree about the synthetic oil and regular changes.

heres the diy i followed with examples from "he who shall be nameless "
http://forums.rennlist.com/rennforum...-diy-pics.html

 

+1 on this advise. I would never pull the fuse for the fuel pump and run the car dry. In addition to the points engine guy has stated, running your car to a stall after pulling the fuse is also bad for your fuel injectors which rely on fuel as its lubrication. Run it dry and you risk harming the seats on the injectors.

Even after an oil change there is still oil left in the internals of the engine so its not like its bone dry up there when you start up.

 

Fuel does its part as a lubricant for many different things, injectors, piston and rings. When fuel exits a high pressure injector it is vaporized as a dense cloud that spreads out evenly.

That fuel interacts with the minimal amount of oil that is lubricating the cylinder walls very evenly, it may dilute it some but it does not wash it away.

Now when fuel comes out of a starving injector it drips and puddles; that puddle has enough concentration and volume it washes away that light lubrication film in spots on the cylinder wall causing small cylinder wall seizures. Then you tack on erratic combustion that is a result of the lean mixture. Flame propagation is not even and constant as it cannot bridge gaps where there is no fuel vapor. Also trying to ignite that puddle causes a slow violent damaging type of combustion as it is compressed into an ever decreasing space; liquids are not compressible!

As per the cranking to get lubrication, that too is damaging. With an oil pump that is in good condition it takes less revolutions to make pressure with a fire up. Also components stabilize faster and more completely at the higher RPM’s and the remaining oil film spreads out more completely thus you get less metal contacts.... And your engine makes more / and higher pressure sooner which drives the oil deeper into the engine and all its galleries.

There really is just so much more to this that I do not have the time nor desire to explain. You can take all my thoughts with a grain of salt as there are many self proclaimed internet experts that are not really that; but lets me say I have spent a great many years helping to design and build engines that have piston sets that are worth more than our complete cars.

I know many a decent mechanic that has told me some crazy wives tale about what to do Vs what not to do; and the internet has just made it all worse.

 

always looking to learn more. you make some very good valid points. i guess the research continues!