Dismantling a Dawes valve showing the correct location of spring and ball, what to look for inside ie oil mist, also how to initially set one up, particularly with the heavy duty spring we have trialled and used successfully.
I found an easier method to make sure you put it back in exactly the same position. Remove it from the lines. Use a vernier to measure the length and jot it down. I think it's about 71mm on mine. However this will obviously vary according to barb length etc on each unit. This gives me about 100kPa boost. Strip, clean and assemble and check with vernier before tightening up again. Works a treat for me.
Mate over the years I've done it every way there is a possibility of doing it, Individual units may be different hence I never put a measurement on it, I just do a simple count and it goes back in exactly as it was. I'm an Engineer by training and have all the gear to measure anything I need but counting turns is so much easier. The experience also allows me an educated guess on what I'd get if I went say another 1/4 turn.
Mate, you know who you just helped, me. Thanks for the great vids. I grabbed a brand new GU 2 months ago and have just finished all the basic mods( suspension, snork, basher, batts, racks, draws, real tail light! etc). I've done all the work myself so as to understand the workings of my new beast as best i can to help deal with any dramas out in the bush. Now I'm looking towards a few sensible mods to the engine, the "daunting"part for me. So thanks again, I'm off to find my Dawes Valve.
Yep, I got it to get my young family out and about a bit and do a bit of hunting with me mates. I'm almost finished my 5m plate alloy boat ive been building for too long, so there will be some long haul towing as well. I dont want a speed machine, i just want a strong, reliable, safe, engine that will get us out of trouble and home again. I'd love to hear your thoughts on Chips (not the salt and vinegar ones) plug n play, hack the ome one? Thanks heaps for your time, I appreciate it.
+Adam Vallance To chip I would do a UniChip above all others, do some homework on them, but as far as I'm concerned they are the most flexible, not the cheapest though.
In the video I say I don't use my needle valve anymore due to my vehicle being happy with my VNT adjustment. I need to qualify that statement, to get to a level of a good VNT setup takes a lot of experimenting unless you are lucky, this includes a lot of needle valve adjustment, particularly if you tow vans/trailers, this is why I would always recommend an in cab needle valve. I have had the VNT down anywhere between 1/4 - 1 turn, it has been at 1/3 turn for quite some time, but still handy.
There were two springs available for the Dawes Valve, I know Darren Dawes from when I was working in US, after a discussion the competition spring became the norm, he actually sent me 50 springs to be distributed to the people I knew who had a Dawes and the original spring had gone soft. if your spring is around 23mm x 7mm then it is the original spring, the comp spring is around 22mm x 9mm. you can stretch the original spring to a certain extent, I actually still have 2 comp springs on the shelf. measure what you have and get back to me. We will see what we can work out.
Hi ive recently removed the three screens in my air filter prior to this boost was set at 15psi max and running around 10psi at 100ks cruising.Now its 114ks for 10 to 12psi and at 100 to 110ks just sits on 15psi constant,boost cuts out at around 18psi. Ive had a tinker with the dawes too far out and it almost stalls on take off but plenty of boost and power cruising,too far in plenty of takeoff but seems to be going into limp when overtaking. So how finnicky are these dawes. 3ltr gu 01,no egt,no needle valve,standard ic,3inch exhuast,dawes valve. cheers any advice would be much appreciated.
+Materoa Wilson Without a needle valve your spoolup will be quite aggressive, so limp would not be unexpected, after removal of my screens and other airbox mods my cruise went up 1.5-2psi with out touching anything else. If you have the HD spring in the Dawes then 1/4 turn in could raise boost 2-3psi. You have a couple of choices, adjust the VNT grub screw down 1/2 a turn or fit a needle valve so you can adjust spoolup very quick and easy.
Hey Geeyoutoo. I have just finished installing my very pretty and expensive HPD intercooler and I am getting limp at full throttle around 100 k’s in 4th gear hitting around 16.5 psi instead of the 15 I was getting with stock leaky IC. To avoid hours of back and forth lottery. Do I need to let Dawes out or take in to lower my boost limit
Took it out, measured the length first and noted it down then opened it and inspected the internals and it is super clean after the best part of 5 years+ use.
Graham Yee Hi Graham, thanks, are you thinking of it? if you are which Dawes valve do you have, the MkI or the MkII? and which spring, the std or Heavy Duty? am currently putting together another video on something that we have come across with the HD spring.
Hi thanks for your reply. I am a chippy so not a real mechanical minded person but i have done most of myself including egt, boots, oil pressure water temp gauges, heater exchange, 4" lift with radus drop arms, aftermarket intercooler and a heaps of other things to many to list. Getting back to the Dawes valve and needle valve, its part of my next project including catch can and egr plat. I purchased the bit off Vic 4x4 & offroad and they did come with some instructions but i am doing a bit more research on how best to fit them and being a total novice trying to get enough information in particularly where to locate the correct hoses to tap into for the valves and catch can and where i should start undoing bolts for the egr plat. I guess this might look abit ridiculous as these would be obvious to most that play with this stuff more often but i love to have a go and most importantly be able to fix a issue for myself or others that might get stuck in the great outdoors. I have found you videos a great source of information to give me a bit of confidence. The dawes valve im not should if it is the mark 1 or 2 but the needle valve is of the newer type that you have featured in one of your videos. If you have any images/ video's of where to locate the above that would be great and i would be forever in your debt. Cheers
Graham Yee See if this links works for you: www.patrol4x4.com/forum/zd30-di-engine-3-litre-71/nads-so-you-bought-zd30-di-heres-nads-installation-steps-logic-88214/index3.html and this which has the full description of the EGR block: www.queensland4x4club.org.au/zd30/ZD30%20Y61%20Reference%20Document%20-%20Colour.pdf Let me know how they go.
