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Another Newbie

R.A.G.S

Member
Messages
31
Reaction score
53
Location
Sydney, Australia
Good day everyone
I have joined the forum to hopefully learn more about the engine I have chosen in my 4x4 besides the bit I have learnt in the past 2 1/2 years.

The engine in question is a 6.5L Optimizer anyone that can help me it would be greatly appreciated!
 
Thanks for the feedback! I have added a signature now its a bit long and drawn out... I will amend that soon but at least anyone reading can understand my worries for the past 2 1/2 years...

I am poised to refinance my home and buy another one but need serious help keeping on top of things, how to treat it, driving habits, maintaining it when various engine parts need to be checked at routine intervals etc..
P.S it has a 4L80E gearbox attached to it, I'm not certain of final diff ratio's
 
Thankyou for your suggestions, I've been quietly reading away through all the sticky notes when ever I get a chance.

I have decided to go forward and purchase a brand new 6.5L optimizer, it's a long motor, so all my periferals (can I call them that?) i.e turbo, intercooler, pumps etc will be used again after being cleaned and tested.
On the old motor I was only getting roughly 17L/100kms (roughly 14.X mpg) I hope I can do a little better this time round.. but I guess (I'm not a mechanic) the same fuel pump will give me a similar result with the new engine...
Is it a definate No No to dyno a new engine to adjust the fuel ratio's? Should I be getting a few 1000 km's up first? or would it be a good exercise to use as a datum so to speak so as the engine is worn in I'll have something to compare to?
 
An old timer mechanic over here that taught Me quite a bit about engine rebuilding, He would explain that new bearing and or cylinder surfaces need to work harden.
I guess that would be similar to the metallic components compressing from the driving forces and the molecules being compressed would make the bearings and other surfaces a little harder than what tjey are right out of the box.
With that in mind, I believe that if it were Me, I would put about 500 miles or so on a fresh engine before running the unit on a dyno to see how it is performing.
That should be about the end of the break in period.
Others might chime in with more info, or, to tell Me I’m full of 💩.
😹😹😹😹
 
if you want that new optimiser to live a long life it's got to be kept cool, 210* is considered to be max. I got 300k+ out of my last 6.5 and have 250k on my current one
Thanks for that info, do you mean never let egt's get above that or water temp? I am monitoring egt's and boost only, the engine temp is a stock Nissan gauge but shows no numbered increments but it never gets to half way as a rule..
 
Thanks for that info, do you mean never let egt's get above that or water temp? I am monitoring egt's and boost only, the engine temp is a stock Nissan gauge but shows no numbered increments but it never gets to half way as a rule..
210 coolant temperature.
EGTs less then 1500 degrees.
What year of a vehicle is this engine going into ?
A nice thing that is suggested is to install a temperature sensor into the back of the right side cylinder head. There is a plug in that postt that can be removed.
I have read that is the hot spot of these engines.
Mine truck is an OBD2 and I also monitor the engine temp through the software. That along with the factory gauge keeps a person mightily informed as to what the temps is doing.
 
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The Car is a 2015 GU Nissan Patrol or Google Y61.
It already has a 2017 6.5 Optimizer motor in it, same exact.
All the undercarriage supports have been modified to suit that engine with the 4L80E gearbox.
BTW I have never seen egt's go over 400*C... I like your thinking on the 7th or 8th cylinder water temp gauge!
 

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Here are the photos after the first engine was newly installed. I’m pretty sure the EGT temp probe is installed at the top of the exhaust side of the turbo. I guess if I have a full head of steam (so to speak) going up a decent hill but maintaining speed of 100km/h I can push 450C but I have never seen it get hotter than that.
the old ZD30 engine in the same scenario would not maintain that speed and would be sitting around 750C by the time I reached the top.
 

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if you want that new optimiser to live a long life it's got to be kept cool, 210* is considered to be max. I got 300k+ out of my last 6.5 and have 250k on my current one
I would of thought being a big diesel V8 that that users expectations would be much higher than 300k on these 6.5’s? More like 500k to 700k minimum, is this not the case?
 
Oh ok so 300k miles as you say is quite expectable then?
I guess here in Australia the average car (sedan,wagon etc) is driven by its first owner for 50,000 to 100,000km’s then sold, second owners drive them to 250,000 to 300,000km’s if they’ll last that long.

My whole mind set for choosing the 6.5L was based on the idea that I can expect 500,000+ kilometres and a good resale price on such a work horse… not that I would ever sell it… they will probably bury me in it..
 
Will do!
can anyone use the old engine? It still runs but without having looked up top yet best guess is worn needle bearings on lifters…
 
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