Jump to content
SAU Community

Recommended Posts

Hi there,

While driving yesterday (35 C heat) the coolant started to leak through the hood of the car. When I had a look it was boiling and vaporizing.

The first symptom seemed to be when the A/C temperature although on the lowest stopped being cold and then I also noticed the temperature gauge go all the way to 'H'.

I've currently got water in in the coolant tank.

About 2 years ago I had the same problem. I believe a radiator flush fixed the issue.

I'm just wondering why is this happening again. Is it expected? or is the problem more serious?

thanks..

Link to comment
https://www.sau.com.au/forums/topic/420064-v35-coolant-evaporatingleaking/
Share on other sites

Firstly, water. I was told never to run water (unless distilled, even though, just don't do it).

Water expands in heat and boils = added pressure on the radiator = fracture. Whether it be a hairline or a large crack, when things heat up, the crack will open up and thus goes your coolant. Water can also cause rust and I've seen some pretty good rust f**k on engines where they've completely disintegrated the inlets.

Secondly, find out roughly what area it's coming from, either front, middle or back of engine bay.

Front - Radiator

Middle - Possibly some hose loose or cracked due to age or other chemicals that could have come in contact and dissolve a part. Highly unlikely that it would be anything serious like engine parts, but it is still a factor to consider.

Rear of engine bay or firewall - Likewise with middle, but could also be the coolant running into your firewall.

I wreck mainly R33 and R34s and with them, yes there an occasional problem but since your car is a V35, I'd guess there would be better stuff in there.

My suggestion:

Diagnose where the coolant is coming from, change the radiator if that is the case.

Pick up sludge or rust remover additive at your local auto store and run it according to the instructions on the bottle (usually has to be left in for a certain ammount of KMs)

Buy Anti-Freeze & Anti-Boil Coolant

Once leak is diagnosed and repaired, additive is added into coolant and run for the specified KMs by manufacturer of the additive, flush and refill coolant with the same stuff you used before.

Bit of work but would save you a heap in the long run, also gives you the peace of mind that it won't happen again, not in your ownership anyway. Also don't run your car when the temp is right up to H. I don't run my 34 higher than 75% of the temp gauge.

Estimated Total cost if DIY: $250

Edit: Don't forget to bleed the air out as well. There should be a screw plug thing within the coolant line that is the highest point of where the coolant runs, unscrew it, run your engine till it sits at its normal temp, get a mate to help or pull on the throttle cable in the engine bay (MAKE SURE IT IS IN EITHER NEUTRAL OR PARK AND HANDBRAKE IS ON, otherwise you will run yourself over with a phantom driver). Leave it off until you get a constant stream of coolant running out. It will spit air, bubbles and coolant out then when all air is bled, constant coolant. Bleeding will require you to replace the coolant lost as it goes. I do this by using a 1.5L coke bottle, cut off at the bottom, no cap and tipped upside down to where the radiator cap is, hold it down firm and funnel coolant in. You'll see the level rise up and down and up again and down lower again as it flows through the radiator.

This is a general idea coming from R33/R34 RB25 experience.

Just search, there are many overheating threads for VQ series engines and they all point back to poor bleeding procedures. (the coolant system is fail in VQ's)

If you can hear a waterfall behind the dash, or if there is a cupful of coolant missing from the system, the whole cooling circuit can airlock causing no coolant flow. Let it cool and top it up fully from the rear bleed point as a start. You may have to re-do it a few times.

Here is a recent thread on the subject.

http://www.skylinesaustralia.com/forums/topic/418084-help-cracked-headhead-gasket/?hl=%2Boverheating#entry6713914

lol yes they're bending you over and using the remaining cash to buy lubricant and lube you up.

Thermostats you can buy genuine Nismo ones on ebay for under $150.

$850 for labor, your judgement. I'm no mechanic but if it's faulty, it wouldn't leak, just wouldn't workand car will overheat unless the thermo stat is damaged itself then fair enough. Get a few mechanics to look at it and see what they say. My guts still tells me that it's the radiator and water problem

It's 3 screws to get the thermostat out, then dunk it in boiling water to see if it opens. You will need to get the water up over 85 degrees before it does, so do it in a pot on the stove.

The mechanic is ripping you, and probably doesn't even know where the thermostat is on the VQ.

Had a mechanic look at it and he said that the thermostat motor is fautly. Replacement/fix quoted to me was about $1000 :wacko:

Am I being overcharged or is this figure correct?

Hmm thermostat motor? If my calculations are correct this mechanic is talking shit.

Chances are it's not bled properly or you have a leak.... or your radiator cap is old and can hold proper pressure anymore.

And xntrq I have to correct you. Whether you use tap water or distilled water it will be the pressure in the cooling system that determines the boiling point. Higher pressure pushes the boiling point higher so if you have a leak or the raditor cap is old you can't hold enough pressure in the system and the water boils.

  • 9 months later...

Hi Mate,
I bought a skyline v35 250gt 2005 model clocked 75000 kms last week,, i experienced pretty much the same problem you had experienced aeround february this year.In one service station they said coolant flush should solve it and in other they said thermostat and coolant flush to be done and gave me a quote of 900$ :(.. please tell me what you ended up doing which solved the issue for you.. need an advice badly,, two days back when i was driving it got so heated up even smoke came a little bit piut of front bonnet and then the cooolant was spilled and fuming,,Is it the thermostat which is causing the problem.Thermostat change with a coolant bleed should solve it??

hI Greenpool,

I badly need an advice on how did ya sort this problem out,, im experincing the same in my V35 250GT,, what solved the issue,, thermostat and radiator/coolant flush fixed it? need a peace of mind here,, thanks!!!

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


  • Similar Content

  • Latest Posts

    • Surely somebody has one in VIC. Have you asked at any shops?  Is this the yearly inspection or did you get a canary?
    • This is where I share pain with you, @Duncan. The move to change so many cooling system pieces to plastic is a killer! Plastic end tanks and a few plastic hose flanges on my car's fail after so little time.  Curious about the need for a bigger rad, is that just for long sessions in the summer or because the car generally needs more cooling?
    • So, that is it! It is a pretty expensive process with the ATF costing 50-100 per 5 litres, and a mechanic will probably charge plenty because they don't want to do it. Still, considering how dirty my fluid was at 120,000klm I think it would be worth doing more like every 80,000 to keep the trans happy, they are very expensive to replace. The job is not that hard if you have the specialist tools so you can save a bit of money and do it yourself!
    • OK, onto filling. So I don't really have any pics, but will describe the process as best I can. The USDM workshop manual also covers it from TM-285 onwards. First, make sure the drain plug (17mm) is snug. Not too tight yet because it is coming off again. Note it does have a copper washer that you could replace or anneal (heat up with a blow torch) to seal nicely. Remove the fill plug, which has an inhex (I think it was 6mm but didn't check). Then, screw in the fill fitting, making sure it has a suitable o-ring (mine came without but I think it is meant to be supplied). It is important that you only screw it in hand tight. I didn't get a good pic of it, but the fill plug leads to a tube about 70mm long inside the transmission. This sets the factory level for fluid in the trans (above the join line for the pan!) and will take about 3l to fill. You then need to connect your fluid pump to the fitting via a hose, and pump in whatever amount of fluid you removed (maybe 3 litres, in my case 7 litres). If you put in more than 3l, it will spill out when you remove the fitting, so do quickly and with a drain pan underneath. Once you have pumped in the required amount of clean ATF, you start the engine and run it for 3 minutes to let the fluid circulate. Don't run it longer and if possible check the fluid temp is under 40oC (Ecutek shows Auto Trans Fluid temp now, or you could use an infrared temp gun on the bottom of the pan). The manual stresses the bit about fluid temperature because it expands when hot an might result in an underfil. So from here, the factory manual says to do the "spill and fill" again, and I did. That is, put an oil pan under the drain plug and undo it with a 17mm spanner, then watch your expensive fluid fall back out again, you should get about 3 litres.  Then, put the drain plug back in, pump 3 litres back in through the fill plug with the fitting and pump, disconnect the fill fitting and replace the fill plug, start the car and run for another 3 minutes (making sure the temp is still under 40oC). The manual then asks for a 3rd "spill and fill" just like above. I also did that and so had put 13l in by now.  This time they want you to keep the engine running and run the transmission through R and D (I hope the wheels are still off the ground!) for a while, and allow the trans temp to get to 40oC, then engine off. Finally, back under the car and undo the fill plug to let the overfill drain out; it will stop running when fluid is at the top of the levelling tube. According to the factory, that is job done! Post that, I reconnected the fill fitting and pumped in an extra 0.5l. AMS says 1.5l overfill is safe, but I started with less to see how it goes, I will add another 1.0 litres later if I'm still not happy with the hot shifts.
    • OK, so regardless of whether you did Step 1 - Spill Step 2 - Trans pan removal Step 3 - TCM removal we are on to the clean and refill. First, have a good look at the oil pan. While you might see dirty oil and some carbony build up (I did), what you don't want to see is any metal particles on the magnets, or sparkles in the oil (thankfully not). Give it all a good clean, particularly the magnets, and put the new gasket on if you have one (or, just cross your fingers) Replacement of the Valve body (if you removed it) is the "reverse of assembly". Thread the electrical socket back up through the trans case, hold the valve body up and put in the bolts you removed, with the correct lengths in the correct locations Torque for the bolts in 8Nm only so I hope you have that torque wrench handy (it feels really loose). Plug the output speed sensor back in and clip the wiring into the 2 clips, replace the spring clip on the TCM socket and plug it back into the car loom. For the pan, the workshop manual states the following order: Again, the torque is 8Nm only.
×
×
  • Create New...