Overheating- need help (Is it the head?
 

Hey there, this is my first post, its going to be long so please bear with me, i have a 2008 350z with about 65k miles on it, it doesn't have any hardcore mods, Greddy exhaust system and test pipe, a d2 racing suspension and a vielside bodykit.

Anyways i bought this car used about 5 months ago (about 60k was on the car that time). It was running smoothly until 4 days ago i heard a weird noise of water boiling or something but temperature gauge was all the way down. I stopped the car for a while turned it back on sound was gone. Now i had it looked over a couple of months ago and there were some hoses that had to be changed that caused the coolant to leak. Whenever i fill it with coolant it gets emptied in about 4 days. I didn't have enough money to change the pipes at that time so i said by the time I get money i will use normal water and fill every 4-5 day. Things that i experienced too is a bit of a shake while on neutral and the car would occasionally shake a bit going up from 40mph to 50mph , I don't know if that is related to this but am guessing spark plugs.


Today morning though, i filled the coolant and start driving, 2 mins down turning it on and driving i smell something burning and the temperature starts shooting up (temp gauge was halfway) ) i park aside and turn it off immediately, i check the coolant it was empty and when i checked the oil it was muddy. I concluded immediately it was a coolant/oil mix. Now am not sure if its the case, i don't have a strong background about repairing cars, but when i saw muddy oil i suspected its a oil/coolant mix and that burning smell was the head gasket toasting.

Any help/suggestions or ideas of what to do now and if this is what it seems like or there might be something else. Am i in deep ****?, and what costs should i keep in mind to repair this.

Your help will be much appreciated.

Comon guys, no one could help me here?

Your problem is very difficult to diagnose over the internet. I suggest towing your car to a mechanic.

If you have any questions I could answer them, i will be doing that hopefully soon for now the car is parked.

If you have any questions I could answer them, i will be doing that hopefully soon for now the car is parked.

If you have any questions I could answer them, i will be doing that hopefully soon for now the car is parked.

Your car has a warped head and the head gasket is leaking coolant into the engine. You didn’t mention anything about the exhaust, but I’ll bet it’s discolored.

That’s not a common problem with the Z.

Well it happened with me so it is now i guess :/

What do you think caused this, is it me not changing the pipes at that time or did i buy the car from a scam, cause he mentioned that it doesn't have any mechanical issues.

What do you think should I do, should I buy new heads and gaskets? and replace them, or should i sell the car or get a new engine

Your feedback is appreciated.

I have read this somewhere is this applicable to my case : (You don't say what car you have, but for quite a lot of vehicles, particularly older ones, that is a do-able job for a reasonably competant diy mechanic. You'll generally need a decent manual, a gasket set & new head bolts, a Torque wrench and a selection of sockets, and make sure to follow the loosening/tightening sequence given in the manual. It is best to get the head checked and/or skimmed by an engineering shop, but you can usually get away without if it isn't too bad a blow.)

Another mechanic told me that even if you change the gasket and cylinder heads engine wont come back to normal working condition, it would be less powerful, how true is that?

Thank you

It could be a case of abuse. Typically this happens when a car is overheated. Repairing this might involve rebuilding the engine. :eek:

I did my RB20DET myself. Inline 6, cast iron block and one huge, heavy alloy head. You should get a machine shop to check the mating surface on each head, as if it's warped it will leak again. They may ask you to remove the cams, lifters and valves, which is by far the hardest part of the job (removal and replacement.) A manual is critical.


While you're at it, replace the timing chain, water pump and any sensors in the vicinity. Any hard to reach coolant hoses too.


If the machine shop has to skim the head, make sure they tell you by how much, as you'll need a thicker head gasket to compensate. I went with one about 25 thou thicker as my shop didn't measure. It worked out well in the end. And the car was more powerful after too!


You shouldn't have to remove the engine from the car for this. Though in your case, if you have coolant in the oil, here's hoping that the bearings are ok... flush it out a couple times when you go back up.

You could be running into a money pit if you don't tread lightly,my best advice is to take it to a trusted Nissan dealership,do your research on Trusted.... dealership you risk spending a lot of money on finding a mechanic not versed in dealing with Nissan 350z's and problematic situations such as this, a fair price to replace head gasket and machine heads and repair should cost between 2500-3000.00 GL!!

Dude, he's in Dubai. US prices are meaningless.

dump the oil. dump the coolant and do a fresh bleed on the coolant? how much coolant are u filling up each time? half a quart?

Status update guys
So i made my research, took it to the stealership and they estimated a cost of 13,000AED equal to around 3500$ so obviosuly.
I searched around and found this garage that deals with german cars I saw some s class getting engine upgrades, g53 engine torn down and so on, so a couple of Gtr's doing some Titan and Brian Crower stroker modifications, asked around a little more and i heard nothing but positive things.
Luckily the owner was a family friend too, he took the car stripped it down in 2 hours. And my heads were perfectly fine, took them to machine shop too to make sure, source of problem was my water pump. It broke out. So i bought the following stuff original nissan, Spark plugs, air filters, belt, water pump, pulleys, tension pulley, heater and radiator hoses, full gasket kit, thermostat, and some other stuff I can't remember for less then 600$ and the garage took from me 300$ for labor including some body work too and a polish.
Car now runs smoothly and powerful then ever!!
Attached are the photos of the car after it got lifted and polished.
https://cimg0.ibsrv.net/gimg/my350z....392b5dfb3d.jpg


https://cimg3.ibsrv.net/gimg/my350z....fd2d1f503b.png

Nice :)


Flares don't look bad (best I've seen on a 350). Not really liking the wheels though (seen too many similar on old Mazda 323's).