ZD30 engines

Quote:

---

Originally Posted by Captain_Rightfoot

Can I ask a mechanical question? Given that I'm an IT person? :D

Why don't chipped td5's have these issues? I've not seen any meaningful analysis that suggests that chipping a td5 results in more issues than running them standard?

We did have a poll a while ago that did show a slight correlation between chipped td5's and exhaust gaskets but it did not take into account the total numbers of chipped td5's so was essentially meaningless. It's my impression that at least 50% of td5 posters on this board have had the upgrade.

All the td5 issues seem to be correlated to poor maintenance rather than usage. (perhaps the early ones did have some issues that were fixed later)

---

Mine runs at around mid 400s to mid 500s when not towing and mid 400s to high 600s when towing, if the hill is long i can keep the EGTs to the low 600s by going back a gear and keeping a trailing throttle.

Baz.

Quote:

---

Originally Posted by Redback

Mine runs at around mid 400s to mid 500s when not towing and mid 400s to high 600s when towing, if the hill is long i can keep the EGTs to the low 600s by going back a gear and keeping a trailing throttle.

Baz.

---

How do you keep a trailing throttle going uphill? Surely you would stop. :p

its that humungous chip!!!
:p

Quote:

---

Originally Posted by justinc

Hi Dougal,

626 was wrong, the pyro tell tale tells me 676:eek:
I mentioned this as excessive, because I wasn't even CLOSE to working it hard, not to mention he tows a 20foot caravan with it! As it is a new engine, I'm not game to push it hard with those EGT's.

Yes, it IS controlled by a MAF sensor, and today I am trying a new one to compare;)

JC

---

Justin, you will need to get it plugged into a computer. That is the signal that the MAF is not right. Think Nissan can check these externally now. Might be worth a try.....

Cheers

Andrew.

Dougal, I remember somewhere in this thread you commented on the YD25. In the Aus spec, these are an excellent engine.
FYI, I heard from our office in the UK yesterday, aparently they cant get enough stock of blocks, cranks pistons and short engines atm as these engines are falling on their heads left right and centre!! Just goes to show how different specs for different countries can have adverse effects on an engine.
Its basically the same scenario as the ZD30TI spec here!

Quote:

---

Originally Posted by LOVEMYRANGIE

Dougal, I remember somewhere in this thread you commented on the YD25. In the Aus spec, these are an excellent engine.
FYI, I heard from our office in the UK yesterday, aparently they cant get enough stock of blocks, cranks pistons and short engines atm as these engines are falling on their heads left right and centre!! Just goes to show how different specs for different countries can have adverse effects on an engine.
Its basically the same scenario as the ZD30TI spec here!

---

Or the different climate??? I was amazed at the short lifespan of the average car/4x4 engine when I lived in Europe. Cold starts for half the hear doesn't help...

Years ago I operated a Cat D7 (I think, G) dozer.
Anyway it was the last of the 4 pot engines, turbo, and down to about 800rpm was when it was doing its best work. (snigging mill logs)
But I was often told by blokes near the machine that the exhaust manifold/turbo was glowing red. I think that machine was replaced at about 9000hrs with no work required on the engine
This makes one wonder how good is the cooling system/block water flow on these new hitec engines. That D7 had a radiator about 5' tall and a massive reverse blow fan.
In the quest for high kw./litre of engine capacity, strict emmission levels, complex electronically controlled engine management systems, maybe the designers have left efficient cooling out of the equation.
Just a few things I ponder upon.
llandro

Quote:

---

Originally Posted by llandro

Years ago I operated a Cat D7 (I think, G) dozer.
Anyway it was the last of the 4 pot engines, turbo, and down to about 800rpm was when it was doing its best work. (snigging mill logs)
But I was often told by blokes near the machine that the exhaust manifold/turbo was glowing red. I think that machine was replaced at about 9000hrs with no work required on the engine
This makes one wonder how good is the cooling system/block water flow on these new hitec engines. That D7 had a radiator about 5' tall and a massive reverse blow fan.
In the quest for high kw./litre of engine capacity, strict emmission levels, complex electronically controlled engine management systems, maybe the designers have left efficient cooling out of the equation.
Just a few things I ponder upon.
llandro

---

The problem is not latent heat with these engines. Its the actual combustion temps rising because of incorrect MAF info to the ECU. The engines dont fail because of overheating, the combustion temperatures get far too high and centre on the piston crown which basically melts. You wouldnt even see any evidence of overheating. The cooling systems do an excellent job of removing the heat, so good in fact you dont even know you have a problem until a piston lets go.

Thanks LMR.
So could this resolve down to a:

Design for high kw/litre displacement.
Low emission levels.
All controlled by electronics.

Seems to me that for the Patrol ZD30, the electronic side is the weak link.
llandro

I am in agreeance on the electronics point. The cylinder head and pistons etc are not much different in complexity to a Td5, yet seldom do I see a Td5 around 650 to 700 degrees:eek: EGT.

I think that if I was able to trick the MAF into reducing fuelling slightly, rather like a reverse of the power upgrade chip interrupter, then it might help these engines last longer. They have impressive power output for a 3litre motor, I would reduce the power slightly if it meant longevity...
Any electronics guru's care to help design a 'less power box' for these vehicles?:)
We could potentially sell thousands;)
JC