Attesa Reservoir Air Pocket

[Gareth]

Hi guys

my Attesa reservoir looks like this :

note this is with ignition off. in this picture air gap is 27mm and fluid is 30mm above max line, when ignition is on fluid level is 25mm above max line, previous owner of the car had this problem in January: http://www.skylinesaustralia.com/forums/topic/418449-r32-gtr-attesa-overflow-or-leak/

when i got the car i got all the fluids changed and mentioned that i thought the fluid was overfilled, so the attesa fluid was changed and the system bled (supposedly) but it was still way over the max line, it wasn't causing any problem and 4wd seemed to be working fine so i didn't worry about it, however after the last time i drove the car (which was in a rather enthusiastic fashion) i returned to the garage a week later to find leaked fluid (same as in post above), it looks as though its just overflowing out of the top when fluid is returning.

from what i have read the air gap is only supposed to be 5mm max, If i bleed the system myself will that reduce that gap? without removing fluid and reservoir to have a good look its a little hard to tell how it works. I noticed that fluid level inside reservoir always seems to be higher than it appears on the outside and wondered if the filter inside the reservoir was abit clogged.

edit: I remember that i had taken a picture when i first got the car, the air gap has definitely increased as you can see:

Edited September 24, 2013 by Gza36

[Gareth]

ok so i read the manual which answered my question whether the air can be bled off, (even if it wasn't exactly clear) is it normal that the air in the reservoir increases over the space of a few months or should it stay pretty constant???

[Gareth]

Ok so it seems nobody cares, but i did a bleed (didn't appear that there was any air in the lines), and unplugged-plugged the connector in the kick panel 150-200 times (i kid you not) and now my reservoir looks like this:

the air gap is now about 7mm, seemed to not want to go any further, but compared to what it was it is a vast improvement and hopefully no more leaking issues!

I'll see how it goes with regards to how fast the gap increases again.

if anyone can post telling me whether or not it's normal for the gap to increase over time that would be great.........

thanks

[Sinista32]

I care - I just don't know any better

If someone does know and posts then I'll learn something too

[niZmO_Man]

Perhaps try pulling the fluid out of the tank then refilling and bleeding it?

[MrStabby]

I'm interested in this too, since i have the same issue. I'm going to try bleeding by putting the car up on stands and putting in gear then cracking the bleeder at the end of the gearbox (pretty sure i read that somewhere, and am not making it up). I did the plug/unplug thing and it would only pump for a very short time. Sounds like you had the same problem. Thanks for posting your progress.

[Duncan]

just leave the engine running (out of gear) if you want to bleed it continuously. Just make sure you keep topping it up.

Also there are 2 bleeders; rear of the gearbox and above the rear driveshaft near the diff

[BNR34boy]

Hi,

I got a GTR34, i would like to change the transfer case oil. Is there a step by step link someone can teach me?

[tricstar]

Hi,

I got a GTR34, i would like to change the transfer case oil. Is there a step by step link someone can teach me?

If it's similar to the 33 ( which I don't imagine the transfercase is much different) just like doing a gearbox or diff, undo the plug at the bottom to drain and then the plug near the top to fill. If ??? It's like the 33 you can fill through the gear stick hole if necessary? But that's the bit you might want to check, not sure with the getrag?

Either way it doesn't affect the fluid in the reservoir in the boot.

[Gareth]

Giving this a bump...still hoping someone can tell me whether or not it's normal for air gap to increase over time....since i got the gap down have done around 1600km in the car, most of this was done in one trip and gap increased a little but not my an amount that seemed stupid. I then did about 20km on an unsealed road where the 4wd was getting quite a workout and then had it on a dyno where the 4wd also got a good workout, i then noticed air gap was HUGE similar to that in the very first picture.

I installed a switch in the kick panel to save me having to unplug/plug connector over and over, it seems that doing this alone did little to reduce air gap size so in the end i bled system, did the switch on/off thing (lots of times) and when it seemed as if it was no longer reducing air gap size i started at the start, bleeding-switching-bleeding-switching. Pretty retarded i know but in the end air gap was back to around 7mm.

In conclusion - The air gap increases much faster when 4wd system is getting lots of use

- My air gap seems to increase at an abnormal rate, somehow air is getting into system?

- 4wd system is working fine as was confirmed on the dyno, fluid isn't leaking out anywhere just air getting in.

If anyone can tell me any of these things it would be much appreciated:

- How big is the air gap in your reservoir?

- Does it increase with time/km? and if so how fast

- If anyone's does increase fast like mine what is the most effective way at reducing the gap back to 5(ish)mm? As my way doesn't seem like the best way at all.

- Has anyone had the reservoir out and apart and understands how exactly it works with regards to the air gap and how the fluid flows around in there, i can't figure out what's going on regarding lower fluid level - air gap - upper fluid level (which seems to be split into a central chamber and an outer chamber???)

Edited April 24, 2014 by Gza36

[tricstar]

From what I have seen there is a fine mesh filter or something inside that could be fixed or maybe skids up and down with the level of fluid. I would say there is something going on with yours? It could be clogged or something creating an air pocket. I would consider replacing the reservoir, might be a bit messy but shouldn't be expensive.

[Gareth]

Thanks for your suggestion, i did wonder if it was reservoir related mine is certainly pretty filthy....i might pull it out and have a good look at it, maybe give it a clean up, i just want to know what normal is with these things so i know what to aim for.

[tricstar]

Pretty sure normal would be no air pocket at all. ( if it is actual an air pocket.) At least that's my experience.

[Gareth]

In every photo i have seen of attesa reservoirs there has always been an air pocket there.......it says in the manual that the air pocket should be 5mm max so i'm not worried that there is one.

What does your resevoir look like?

[-Tom]

This is mine when it's primed. The liquid goes up about 2-3cm when the car's off though.

I've always seen air pockets in all reservoirs as well, so you're not wrong.

[tricstar]

Shit this is my second GTR and I have never seen the air pocket, so just went to take photo with my phone and bugger me if it doesn't show up that little white ring ( only about 5mm ) couldn't really see it until the flash went off. So I will stand corrected. Sorry for the bum steer.

[Gareth]

This is mine when it's primed. The liquid goes up about 2-3cm when the car's off though.

I've always seen air pockets in all reservoirs as well, so you're not wrong.

Thanks for the picture, does your air gap change at all?

Mine must have a leak somewhere that is allowing air to get into the system when 4wd is engaged....how annoying...i reckon the problem isn't with the reservoir itself, somewhere else in the system.

[-Tom]

Thanks for the picture, does your air gap change at all?

Mine must have a leak somewhere that is allowing air to get into the system when 4wd is engaged....how annoying...i reckon the problem isn't with the reservoir itself, somewhere else in the system.

Yeah it does change, but no real issues with my AWD so I don't worry about it too much!

[Gareth]

Yeah my AWD works fine, the main problem is when i leave it and the air gap gets so big the reservoir starts overflowing.

If anyone else can tell me how theirs goes, how often they have to bleed to reduce the gap or anything else helpfull i'll be keeping an eye on the thread so even if it gets abit old...post...i'll get it

thanks

[Gareth]

update time...

cracked the shits with my reservoir, air gap was getting stupid big with f*all driving so i pulled the reservoir out of the car to have a good look inside to figure out what's going on in there and give it abit of a clean out.

So for anyone who wants to know what the inside of their reservoir looks like:

note that there is also a sensor in the middle of the reservoir which i think may be just a low fluid level sensor, it's just a cylindrical thing that floats up and down with the fluid level (and this is what the wires that come out of the bottom attach to), this is what causes the change in colour effect in the tank (the pink fluid that you can see at the top of the tank is above the maximum height the sensor can travel to, the fluid at the height of the sensor and below appears darker because of the sensor and below that the filter).

After i had had a good look and given it a clean i put it back in the car and bled the system, end result:

When the manual talks about a 5mm air gap i think what they actually mean is a 0mm air gap, in the photo above there is 0mm of air, but the plastic that separates the top and bottom chambers is around 5mm thick and from the outside looks like an air gap.

My leading theory now is that one or both of those little things you can see on top of the lower chamber (first picture) are supposed to let the air out and mine are clogged up and not doing their job properly, when i had the reservoir out and gave it a blow with the compressed air it temporarily unclogged these bots and allowed me to expel all of the air. now of course it's clogged again and my air gap is once again growing.

I think my next course of action is going to be to try another reservoir and see if it makes any difference.