Ok thats interesting I just removed dawes to check against the compressor, and the dawes is full of water? what or where could water possibly come from?
Ok thats interesting I just removed dawes to check against the compressor, and the dawes is full of water? what or where could water possibly come from?
Originally Posted by Otech66
Technically you are not correct as variable geometry geometry turbo chargers don't have waste gates.
What they have is ability to change the exhaust turbine profile which changes/controls the speed output.
This in turn controls how much air pressure and how quickly is pumped by the compressor wheel on the other end of the turbo.
So by manipulating/slowing down the compressor maximum boost is controlled.
In ZD30 case the vanes in the exhaust side are retracted or raised against the exhaust flow thus controlling the output.
All the Dawes valve does is to bleed the vacuum (used to actuate vanes in to raised position) when boost pressure reaches set limit and vanes are retracted slowing the turbine as oppose to fixed geometry turbine where we bleed exhaust gases via waste gate after boost limit is reached.
Similar action but different means of actuation.
Are you sure you the water has not been introduced in there from your compressor? Compressed air usually contains air moisture so frequently stays in the pressure tank unless one has an airdryer fitted or drains the tank regularly.
Cheers
Last edited by Rumcajs; 16th April 2014 at 08:46 PM.
no when I went to remove the dawes from the car I pulled the pipe off and my son said looks like water came out, so I unscrewed the dawes and it was full of water around the ball bearing, i'm just wondering I have a snorkel fitted if water could have been laying in the bottom and sucked in through the air filter?, anyway cleaned dawes and calibrated then fitted back to the car, hitting about 12 psi, but haven't experienced any limp mode, just a little laggy in 4th and 5th gear, but rockets through 1,2,3 gears, egt sits around 350 cruising and hits about 450 on a hill, but cruising at 100kmh boost is only sitting between 6-7psi? dont think ive got dawes set right just yet
Water shouldn't be in the Dawes valve, how is it going to get there? Unless your engine is ingesting water through turbo charger or elsewhere?
Do you have a needle valve fitted too or is the ECU still controlling the VNT.
Average boost pressure at cruise/100 km/h should be around 10-12 psi but that also depends on engine load.
Cheers
Yes have needle valve installed as well also EGR blanked
Hey Rickie. Try raising the boost levels up to just below the limp mode limit. Then re adjust the needle valve. Most Patrols see a limit of 15-16psi. With that you can easily get 10psi at 100clicks. A lower max boost will result in a lower mid range boost (at 100k's).
It is very daunting and frustrating when setting these up for the first time. But once its done, its done for good.
Rickie3 (17th April 2014)
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