Outer Limits 4x4 Board

mkpatrol wrote:Question Bogged & Murcod, are you involved in the automotive industry..

Nope work with computers. worked in m/bike shops for yrs, raced bikes, had more mates into V8's than turbo..

http://www.hksusa.com/categories/?id=1091


The number one cause of turbo failure is oil "coking". Oil "coking" occurs when a turbocharger is not properly cooled down and the oil that normally lubricates the center cartridge heats up and forms solidified oil deposits. A turbo timer allows an engine to idle for a preset time after the ignition key has been turned to the off position and removed. --- By allowing a turbocharged engine to idle, oil continues to pass through the turbo until it has cooled down to the point where oil "coking" will not occur.

In 1982 HKS was the first company to offer a commercially available turbo timer, and has since been the leader in turbo timer technology.

*HKS systems are compatible with most OE and aftermarket security systems and will allow the engine to run ONLY if the parking brake is engaged

What they dont mention there Bogged is poor oil quality leads to "oil coking" as well & is probably more likely the cause.

I will get back to you with some info.

Have a look at this Bogged

http://auto.howstuffworks.com/framed.htm?parent=turbo.htm&url=http://unitedturbo.com/basics.html


Oil coking will damage it over time but switching the engine off when the turbo is spinning fast will cause damage almost instantly.

If vehicle manufactures thought there was a problem with cooling they would fit turbo timers to every vehicle.

mkpatrol wrote:Oil coking will damage it over time but switching the engine off when the turbo is spinning fast will cause damage almost instantly.

If vehicle manufactures thought there was a problem with cooling they would fit turbo timers to every vehicle.

If vehicle manufactures thought there was a problem with their turbos spinning at speed of sound as people stopped they would fit turbo timers too.

Ask yourself how many people sit there with their car at 4-9000rpm so their turbo spools up flat out as they park? You usually idle into a park,or driveway, or carpark, or camp ground etc so turbo is spinning slow enough to 'roll' to a stop.

Now your mis quoting me about the 4-9000rpm thing. A turbo spins faster & produces more boost under load. If you rev the engine in neutral it produces far less boost which = less rpm.

This is my point about how to look after the turbo without a timer. Its not essential not will it guard the turbo forever & a day from damage.

As far as high revving before you switch the engine off. My favorite fishing spot has a hill about 3km long before you come to the gate of the caravan park. When I tow my mates boat down ther it is a long hard slug in 3rd & as you get just over the crest there is a gate. Now I could just pull up & switch off without another thought.

I can think of about a thousand other circumstaces.

mkpatrol wrote:Now your mis quoting me about the 4-9000rpm thing. A turbo spins faster & produces more boost under load. If you rev the engine in neutral it produces far less boost which = less rpm..

What I was getting at is you dont drive at 90kph (theres your under load)then stop dead and shut the motor off. You drive slowly upto a stop, then the turbo naturally winds down while you are slowing down.

I can hear my turbo thru the zaust. You can hear it wind down from a drive, or even when you rev it

It doesnt take 5 mins to wind down, more like 5-10 seconds at the outside. So why do timers have settings of 1-5 minutes?

How long do you think it takes for a turbo to wind down from max RPM? 5 minutes? - thats the speed of sound comment

You are right about the 5 minute thing, it usually takes abit longer than 5-10 seconds though. 30secondt to a minute is safe.

I only used that as an examle as I see people with their timers set for 5 mins for no reason.

The reason they have 1-5 min intervals is to suit a variety of applications.

The thing is though, not even the race drivers use them. I have been in a couple of rally cars which are on the top of the heap here in oz & they dont have them.

They only run them for half a minute before they shut them down.

mkpatrol wrote:The thing is though, not even the race drivers use them. I have been in a couple of rally cars which are on the top of the heap here in oz & they dont have them.

They only run them for half a minute before they shut them down.

... and all the top race drivers in the top of the heap would pull their engines down at end of each event. most would rebuild them while at it.

Cost is of no issue to them.

Most drivers in the top events you mention dont even own the car themselves.. why would they care? it would be rebuilt at end of event, as most times they play with the pitch of the turbo for different events.

mkpatrol wrote:Question Bogged & Murcod, are you involved in the automotive industry. I am not trying to be a smart alec just looking for some background as to who Im talking to.

Yes, I have worked as a employee in a EFI performance workshop. Also did "voluntary" work in another performance workshop after hours. Have owned two boosted turbo vehicles- one was used as the test mule to develop a local company's boost controller.

You haven't said what you do?

You also haven't answered my question about how long you think a turbo will keep spinning fast once the throttle butterfly is closed....

Mechanic, 17 years. Used to work in a workshop fitting turbos for ARB.

Worked in the aircraft industry fro 4 of those years, now work for government in motor vehicle area.

mkpatrol wrote:Mechanic, 17 years. Used to work in a workshop fitting turbos for ARB.

Quick Phone call to JPC today.

Reason for timers is to let turbo cool down.

You can get Nissan Factory turbo timers to suit the GU
My dealership has them but am not bothering with it really i dont want to leave the car in gear when i leave it.

price was $250 fitted
Nissan ferntregully
(03)97584444

got turbo timer on my hilux, arb one, earthed through the park break so it will only work when the parkbreak is on... let it off while the car is running on the timer and it stalls... works fine with hornet alarm fitted except that when i first got it the shake of the deisel when it shut down was enough to set the shock sensor off.. alittle bit of ajustment fixed that...

in regards to a turbo taking so long to wind down, bullshit.. turn your car off and the turbo stops within 5 seconds, to back this up, ive had the inlet piping off to a point i can see the fins of the turbo, had someone redline the car(4500rpm) then shut it off without letting the throtle off.. once the pistons arnt pumping the air cant go anywhere so the turbo stalls within 3 or 4 seconds easy

Look at a pyro on a truck, If the engine is working hard then the exhaust temp is high, let it idle and the exhaust temp drops. So T\timers are both for letting the turbo spin and cool down. Most haul trucks (dump trucks) leave the timer on for 3+ mins to let the engine cool down as well minimising after boil when the engine is shut off....