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Excess Oil Usage - The Final Chapter

2727 Views 22 Replies 12 Participants Last post by  sundog
I recently posted an update to my saga with excess oil consumption on my Z and how Nissan were going to invalidate 8 months of 5000k test measurements because they said my use of M1 oil wasn't 'to spec'. Well I have had an interesting couple of weeks since I was told that news and quite a few of you told me to stick to my guns and fight the good fight.

Well, this morning after much stuffing about last week with customer support who never called back and had no idea what would happen if the tests did prove positively that there was a fault, I have had a satisfactory conclusion.


Yep, my car goes in to get a short engine replacement next week. I'm told that a 'short' engine is the complete block but minus the head (I can stand corrected if anyone knows better). I thought they may do a rebuild, put in new rings or something like that but to replace the engine was quite unexpected.

I have to go to the HQ in Dandenong, drop the car off and get a loaner for two weeks (probably three weeks is more realistic).

Wonder if the new block will the a 35th Ann version, maybe I'll score a couple more Kw out of all this.
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Good news!

You are correct. Short block = bottom end (block, pistons, rings, rods, crank, case, etc). Long block = entire engine minus components.

As for the new short block, I hope everything turns out well. It should fix your issues. I don't know the answer to this, but I thought I would ask. Can oil leak through at the valve seals enough to cause consumption issues? If so, would it not take a long block or new heads to fix the issue? Just curious.

As for your situation, this is a not a common problem, but it does happen. It is just a rare bad build. I think it affects about 0.5% or less of the engines.
Haven't a clue about valve leakage. But I imagine I will still have to do the 5000k tests after the replacement to ensure complete rectification. If it is still there then maybe the head would be the next thing to get replaced.

The problem was a strange one, no oil leaks, no visible oil burn, I just lost 1.25 litres every 5000k when I should have lost about .25. Only time will tell.

I was just surprised that they admitted to it firstly and that they had a motor in-country, the excuse is usually a 2 month wait for a Japanese delivery.

Do you think I should take off the Hi-Tech cat-back before handing it in? I still have the stock exhaust in the garage. I don't want to give Nissan any BS excuses to back out.
I'd say take it off anyway, in case it comes back without it.
absolutely remove the exhaust, I am surprised they have agreed to this with an aftermarket exhaust on.

we are about to start out complaint about oil consumption too, we are getting thru a fair bit more than you, also with no visible burnt oil or leaks...odd.

but a new short motor sounds good to me.
I wouldn't be so paranoid about the exhaust, it's too late anyway. They would have already noted it when previously inspecting your car and would not have agreed to the 'engine' swap if it was of concern.

A car manufacturer would have to stoop very low to blame engine oil usage on an aftermarket exhaust......don't worry!!

Good luck Duncan.

Sundog - was it Randwick Nissan that finally agreed on the shorty?
:OMG: I finally picked up my car with the replacement engine (short) today!!

I've had a Nissan loan car for the last few weeks (Auto X-Trail :rolf2:) and I've been going nuts waiting to get back into a car that doesn't have to think about whether to respond to a request to go faster.

It took a bit longer than I was told but I've got what I wanted and I must say Nissan were pretty good about it once I'd spoken to the right people, the people who actually wanted to help me. Thanks Val & Jamie.

Had a quick chat with the service manager at Blackburn Nissan (they managed the replacement) about running in. Casting my mind back to the thread we had a few weeks ago about this topic. He basically agreed with the premise we seemed to come to that driving aggressively (but not thrashing) was the way to go for the first few hundred clicks. Lots of up & down shifting, varying the revs, keep away from under-rev stress etc, seems pretty logical to me.

No mention of the Hi-Tech, but I think it (the replacement) was a pretty big deal for them, probably a first for most dealers I'd guess.

I got the car home, pretty stoked that I'd got my butt back into the seat of a car with a bit of toe. Backed it into the garage, I love that paint burning smell of a new engine, smells like ...victory... (apologies to Robert D).

I'm a happy camper. :shiftdrive:

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Congrats Jim - glad that it finally all worked out for you.
BTW, Ford have done may short block and long block replacements on their XR8s, due to severe pinging problems, so although yours may have been the first Z in Aus to have a short block, other manufacturers are well versed in this technique.
We've just started our oil monitoring process this week...hopefully we'll have the same result soon.

Great to hear it turned out OK :D
Congratulations Jim on the new shortblock, how is the run in procedure? Are you taking it easy or are you gunning it?

Duncan, how did the dealer treat you? Did they give any problems and were they in denial about the issue? If they were ok, I'll see them next week about the gearbox and seat issue.
Hello Jim'

Good to see your car on the move :)

Met you today on my Dad's HSV :p i guess you don't know it's me.

Just saying hi ;)

Well we are trying a new dealer, they were pretty confident there would not be a problem....lets see what they say when they see how much it gets thru ;)
Hi all,

I've had the new donk in for a week now, done about 900km. I've been giving it a bit of wellie but driving to work in the city each morning makes it hard to run it under suitable load, too much stop/start to be really effective. I was hoping to get a weekend away where I could gun it around the Great Ocean Rd down to Port Campbell but haven't had the opportunity (exams..sheesh!).

I've been unable to find out when the engine was manufactured, I'm hoping it's a later build and maybe the 35th Ann. version, who knows.

I have been conciously keeping the car in 3rd much more than I normally would and varying the rev range, purposely avoiding low 2s to 2.5k/rpm in anything more than 2nd. I don't think its been into 5th much at all on the last 900km.

The engine note is actually deeper (with the Hi-Tech) than the old engine. I wonder if it will change any more as it gets run in?

The hot paint smell hasn't gone away yet, it stinks when you park it.

A point to watch out for for the uninitiated that score a new shorty, the engine block comes without an engine number. Nissan are supposed to stamp the old one on to the new one. Therefore you won't have a new engine number and no need to change rego details.

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What is considered excess oil usage?

I know we have the display that shows us the oil consumption what is normal?

I get around 8.2-8.7km/litre

I do a fair bit of highway driving M4.

I do have a Automatic version so that might account to slightly higher oil consumption.

Anyway what do other auto owners think? (is there actually any auto owner here! LOL)
I HOPE you're talking about fuel rather than Oil!!!

If you're using that much oil, you've got a problem. I would suggest you get under the car and see if the sump plug is in.

Or, if the performance is a little off you may have a piston hanging out the side of your block.

As always

lol... you're talking fuel usage vs oil!

You wouldn't make 40km with usage like that... As for fuel economy it's pretty good. I manage 7.5km/lt but i drive like I stole the car most of the time.
Actually they are required to stamp a new engine on it, you might have trouble with this car in the future. I would strongly suggest calling your local transport department and clarifying this.

I changed an engine on a previous car, it required a blue slip and a new rego sticker. In this case I will be expecting Nissan to cover these costs.
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