3.0 litre EGR/Butterfly/Swirl Mod

[tweak'e]

egr should not make any different to max boost as egr is off at full throttle anyway.
easy enough to test if you can remove the blanking plate.

otherwise i'm not sure.
check if the bolts holding the waste gate are not loose. some of the turbo bolts are a little prone to coming loose.

 

[04SilverSTR]

I'll second the tweak'e about the waste gate bolts

 

[BP90]

Are they just the 2 bolts that hold the wastegate actuator bracket onto the top of the turbo housing? If so that bracket had a little bit of movement in it so i knipped up them bolts and then the 2 bolts on the oil return flange needed tightening up (the pipe that goes from the bottom of the turbo back down to i think the sump) not sure if boost could leak from here but i knipped them up anyways..

Will see if either of those made a difference tomorrow on the way to work.

Thanks for the help fellas.

Bart

 

[Old.Tony]

Blocking EGR doesn't reduce EGT it increases it. EGR is exhaust gas - it is NOT oxygen. The whole idea of introducing EGR into the combustion chamber is to reduce the combustion temperature and make the combustion process less complete - and by doing so, the temps aren't as high and thus won't produce as many oxides of nitrogen.

By blocking the EGR you take away the dampening process and INCREASE the temperature.

There is a temperature drop across the turbocharger's turbine, but that's because the energy in the exhaust gas is being consumed by rotating the turbine - but in a nutshell, the presence of EGR actually dampens everything. Blocking it makes it all go harder.

That means your problem is likely to be elsewhere and if Tweak'e is pointing at the waste gate, that's where I'd be looking before anywhere else.

As for blocking the EGR pipe at the exhaust side, do NOT use aluminium. Al goes soft at 700C and where an EGR-operational engine might see EGTs around 650-700C, once blocked your EGT could rise over 750-800C (our D40s have seen 900C). Al melts at those temps. Use stainless, about 2mm thick or better. You can use mild steel, but that will be affected by condensate (water created in the combustion process) which will rust the plate just the same as your exhaust rusts.

 

[BP90]

Yeah i nipped up all the bolts on the back of the intake side of the turbo housing wastegate bolts. The exhaust side were already tight. Will see if that changes anything. If not i will go buy some replacement hoses for the intake pipe between the turbo and the intake. To rule out the worn or misalligned hoses. As they are getting a bit worn.

Also just had a read through a thread on here about boost leaks and the last comment was mooxie saying to find leaks on exhaust side of things use soapy water (which i have been) and on intake joints use aerostart while someone holds the revs at 2000rpm and see if anything surges.

Do you guys rekon aerostart is safe to use for doing that?

And i was leaning towards stainless, would 3mm stainless be ok to use or best to stick with 2mm Old Tony?

Bart

 

[tweak'e]

Blocking EGR doesn't reduce EGT it increases it. EGR is exhaust gas - it is NOT oxygen. The whole idea of introducing EGR into the combustion chamber is to reduce the combustion temperature and make the combustion process less complete - and by doing so, the temps aren't as high and thus won't produce as many oxides of nitrogen.

By blocking the EGR you take away the dampening process and INCREASE the temperature.

sorry tony thats not quite right.

you missed that egr reduces PEAK combustion temps (ie flame temp) to reduce Nox. but because it generally increases intake temps it increases the average temp which is what you measure as EGT.

 

[Old.Tony]

2mm stainless ought to be enough. If you've got 3mm it's probably overkill.

I didn't think there was enough EGR to influence the temps anywhere near as much as the combustion process. Pages like the Huber Group info on EGR systems (that they design) seems to support that idea. I really should put my EGT gauge in and see first hand!

 

[tweak'e]

diesels run big amounts of egr, at a guess probably 20-30%, and on the ZD30 the egr is not cooled. so egr at 300c+ removes quite a bit of the cooling capacity of the incoming air.

 

[BP90]

Well the nipped up turbo bolts (bolts holding wastegate brakcet and the 2 below them) did nothing for lowered max boost pressure.

So going to replace the intake hoses and see if that makes a difference. If it doesnt i guess i will have to block off the exhaust side egr flange joint. Getting a bit of a f@uck around to find the source of the lowered peak boost level.

Bart

 

[jaymac90210]

G'day fellas, I didn't seal up around my blanking plate with gasket glue or anything, would that be detrimental to my nav in any way?

 

[Old.Tony]

It could foster a leak - either of exhaust which will reveal as a black sooty stain around it, or as a boost leak, which will shriek at you every time you put your foot down.

 

[jaymac90210]

It could foster a leak - either of exhaust which will reveal as a black sooty stain around it, or as a boost leak, which will shriek at you every time you put your foot down.

Thanks Old Tony, I'll get onto that asap haha. Would you hear the air coming out much like a rustling noise below 1800 rpm whilst decelerating? Trying to nut out a noise that is coming from my engine haha BUT OF COURSE when I go to show my mechanic it never makes the noise!

 

[Old.Tony]

As the car is decelerating, the turbo shouldn't be doing a whole lot since there's not a lot of exhaust pressure. I suppose there could be some fluttering - I'll pay attention to mine and see if mine does it.

If it was Krafty's car I'd suspect the bottle of Brown Muscat in the paper bag rolling forward in the passenger footwell.

 

[jaymac90210]

As the car is decelerating, the turbo shouldn't be doing a whole lot since there's not a lot of exhaust pressure. I suppose there could be some fluttering - I'll pay attention to mine and see if mine does it.

If it was Krafty's car I'd suspect the bottle of Brown Muscat in the paper bag rolling forward in the passenger footwell.

Okay great thanks for that Tony haha oh how I wish that is the problem for me was!!!

 

[jaymac90210]

I suppose the car is getting old and won't stay new forever... 2003 model haha

 

[adamp]

hey i just bought my self thats blanking plate off ebay and it turned up today. i'm all keen to put in it but there is a few questions i want to ask before i do it.
now i cant remeber where i read it on here but i want to no for sure. i think i read on this forum somewhere that the egr is also used for cooling EG temps am i right?
this is the main reason y im not going straight out there and putting it in my ute because if it dus raise the temps id prefer to wait till i get a pyro gauge so i can see wat the temps r doing

at the end of the day i just dont want to put it in then bang i just melted a hole in my piston

 

[Rumpig]

If you haven't got a chip you won't melt a piston and the EGR is more an emmisions thing than engine cooling. The EGR block can cause a check engine light on some of the newer D40s that measure egr flow.

 

[tweak'e]

at the end of the day i just dont want to put it in then bang i just melted a hole in my piston

read a few posts up from this one ffs !

http://www.navara.asia/showpost.php?p=252752&postcount=386

 

[180degrees]

hey i just bought my self thats blanking plate off ebay and it turned up today. i'm all keen to put in it but there is a few questions i want to ask before i do it.
now i cant remeber where i read it on here but i want to no for sure. i think i read on this forum somewhere that the egr is also used for cooling EG temps am i right?
this is the main reason y im not going straight out there and putting it in my ute because if it dus raise the temps id prefer to wait till i get a pyro gauge so i can see wat the temps r doing

at the end of the day i just dont want to put it in then bang i just melted a hole in my piston

It doesn't raise any temps, in fact your cooling system should run slightly more efficiently due to not having to cool hot exhaust gases (the metal pipe that runs parallel to the front of the engine is the EGR cooler.

EGR gases come out of the exhaust manifold pretty dam hot, the cooler does just that cools them down since colder exhaust gases have a higher reduction in NOx and other greenhouse gas production, basically it retards the combustion process to make it more environmentally friendly at the expense of your engine.

 

[tweak'e]

It doesn't raise any temps, in fact your cooling system should run slightly more efficiently due to not having to cool hot exhaust gases (the metal pipe that runs parallel to the front of the engine is the EGR cooler.

EGR gases come out of the exhaust manifold pretty dam hot, the cooler does just that cools them down since colder exhaust gases have a higher reduction in NOx and other greenhouse gas production, basically it retards the combustion process to make it more environmentally friendly at the expense of your engine.

wrong engine. this is the zd30 thread. no egr cooler on them.
the later yd25 has the egr cooler.