All over the show

[Rickie3]

Just installed my pyro and boost gauge into my 2000 3 litre patrol as i'm getting ready to install the dawes system, took the old girl for a spin and i'm a no brainer to these things!,have to say ive also installed a brand new straight through 3 inch exhaust not cat or muffler, when I hit a slight hill the EG climbed to just over 500 degrees, when cruising at 100kph sits around 300 is this normal? also the boost gauge is all over the show, gauge is a Speco boost gauge, boost gets to around 9psi then all of a sudden drops to 0 under accleration, then spikes to 15 then just drops again, its like its loosing vacuum, I did notice the intercooler is showing a small sign of oil weep? when cruising the boost sits at around 5psi then just drops again,then comes back to life and shoots up to anything to 10-15psi its like the needle has a mind of its own, can anyone offer some advise please as to what could be causing these weird things with the boost gauge, oh and its a brand spanking new gauge

[mudski]

The boost being all over the shop is normal for these Patrols. Hence why we fit the dawes and needle valve. You will also see your EGT's will be lower too. Also if your IC is leaking you will be "pissing in the wind" trying to set the dawes valve. Any boost leaks and you will just be winding the dawes in and you r boost levels won't rise. You need a 100% sealed intake system for the Dawes to function correctly.

[Rickie3]

I had the IC down the metal shop it sat there for 3 days untouched, so pissed off they didnt do it, so I just bought it home and put it back on as I was eager to hear how my new exhaust system sounded plus try out my new gauges, the IC will be taken out and sent to another shop, I want the tanks removed and seals taken out then welded up and pressure tested my mate has his done and it made a huge difference, is it also possible to have a vacuum leak from the gauge to the intercooler pipe?, I used plumbing tape on the gauge end

[Rickie3]

I dont intend on installing dawes till I have the IC done, also do you consider EGT over 500 extremely high on a very slight hill and also under acceleration on straight flat open road?

[mudski]

It is possible to have a vacuum leak. Anythings possible. Make sure things are sealed up and you will be right. As for the EGT's. I think 500c is high. Others may not. Considering mine sits at 200'c on the highway. Have you blocked the EGR?

[Hodge]

Rickie, my CRD used to hit 500 easy up even a slight hill. This was before the dawes and needle were installed. After it the boost was more stable and I'm yet to see it go above 400. Then after that the new non leaking IC was fitted and that dropped my EGT's even more.
And like yours, before I installed everything, my boost was a yoyo, just bounced all over the place.

[Rickie3]

Have you blocked the EGR?Not yet Mark, was going to install that when I do the dawes

[Rickie3]

Rickie, my CRD used to hit 500 easy up even a slight hill. This was before the dawes and needle were installed. After it the boost was more stable and I'm yet to see it go above 400. Then after that the new non leaking IC was fitted and that dropped my EGT's even more.
And like yours, before I installed everything, my boost was a yoyo, just bounced all over the place.Oh this makes me feel better, I was thinking ive done something wrong

[Rickie3]

This is the exhaust system I bought http://www.ebay.com.au/itm/251465696344?ssPageName=STRK:MEWNX:IT&_trksid=p3984.m1497.l2649 , it fitted up perfectly without any mods to it, all I did was weld on a nut for the pyro gauge sensor, cant say i'm 100% with the system it sounds really fluttery when idling, and I am actually surprised that its rather quiet

[mudski]

Why did you buy a zorst with no cat?

[Rickie3]

I can never understand the reasoning for a cat on a diesel motor in the first place

[mudski]

I can never understand the reasoning for a cat on a diesel motor in the first place

Because its the law. On modern engines the cat doesn't affect the performance. If you can call it a modern engine.
You dont wanna get caught by the rta...

[Rickie3]

I'm tasmanian mate I have 2 heads and not one brain amongst them, RTA dont give a rats about 4x4's here, they just interested in trucks

[MEGOMONSTER]

I'm tasmanian mate I have 2 heads and not one brain amongst them, RTA dont give a rats about 4x4's here, they just interested in trucks

Lucky you.

[Rickie3]

Had the IC preasure tested and it appears ok, so ive installed the dawes kit and blanking plate, ive followed the paperwork that Mark sent with the dawes, but am a little confused, it says wind the needle valve right open so no flow restrictions, I assume that means open so air can pass through? which I did, I wound the dawes in a tad till I couldnt hear the ball bearing rattling, I then went for a drive and the boost gauge didnt even move, so I pulled up and closed the dawes a little more, but still no reading on the gauge, so pulled up again and wound the needle valve right in then slightly out to roughly 1/4 inch and this time the boost gauge shot up to around 22 PSI, so pulled up again and wound out dawes a little and got back to a tad under 15psi, but have been hitting limp mode at 2700rpm, cruising at 100kph with accelartion sits just under 10 psi,can someone give me some quick guidence please where i'm going wrong

[Sir Roofy]

Back it of till you hit 12 psi or less think mark runs at 10psi

[Rickie3]

Back it of till you hit 12 psi or less think mark runs at 10psiback the needle valve off?

[Rickie3]

ive just disconnected the dawes valve and I can pretty easily suck air through it even when done up tight is that normal?

[Paule]

Don't no if that's normal as I've never tried. If you are getting limp mode you need to back your Dawes valve off. With your needle valve you set it up while idling so the turbo actuator just moves off it's stop

[mudski]

Had the IC preasure tested and it appears ok, so ive installed the dawes kit and blanking plate, ive followed the paperwork that Mark sent with the dawes, but am a little confused, it says wind the needle valve right open so no flow restrictions, I assume that means open so air can pass through? which I did, I wound the dawes in a tad till I couldnt hear the ball bearing rattling, I then went for a drive and the boost gauge didnt even move, so I pulled up and closed the dawes a little more, but still no reading on the gauge, so pulled up again and wound the needle valve right in then slightly out to roughly 1/4 inch and this time the boost gauge shot up to around 22 PSI, so pulled up again and wound out dawes a little and got back to a tad under 15psi, but have been hitting limp mode at 2700rpm, cruising at 100kph with accelartion sits just under 10 psi,can someone give me some quick guidence please where i'm going wrong
O.k. With some cars you need to wind in the needle valve right down then back it off until the rod on the turbo drop about 1/4inch first. Whilst the car is idling. Then try again with your dawes. I have found that some engine react differently to others. As i found out with Paule's car.
Just read what you have done its its good so far. If your hitting limp mode open the dawes up more until your just undet that threshold of limp mode. Then you can re adjust the needle valve.
Unfortunately some ECU's will only accept a lower boost. Some will only accept 14psi, some will accept 18psi. As Paule's did.
The only ways around this is to increase your air flow volume. By using a k&n air filter, which I do, a hi flow air box lid and maf housing, (expensive but very effective), snorkel, or a maf voltage modifier. Never tried the last one as I have the hi flo lid and housing.
Oyu will eventually get there and find the sweet spot. Takes a bit but you will get it.

[mudski]

On which end? It seems the dawes is doing its job though as you can limit your boost....


Back it of till you hit 12 psi or less think mark runs at 10psi

On the highway I run 15psi...

[Rickie3]

After pissing around for hours today and achieving bugger all and $50 worth of diesel, no matter what adjustments I made I couldnt get the boost gauge to register anymore than 9psi, and basically non responsive no matter what, so I pulled the IC off, and sure enough I could see signs of fresh oil seepage in 2 different spot, so the joint that preasure tested had NFI what they were doing, also the pipe that runs from the IC back onto the turbo where my boost gauge line was plugged into, is as dodgey as hell, a previous owner had installed a brass joiner, but must have broken it and it had all this black crap like plastic melted over it as quick fix, I hit this crap with the grinder and the brass piece had a huge hole in it, so I'm 100% guessing this is why i'm having issues with little to no show on my boost gauge, on idle the needle valve is doing what it should, so the loss of vacuum is the problem with the boost gauge, so the IC will be taken in tomorrow tanks removed and welded up, then presure tested by someone who knows what there doing, so do you guys think those sus areas would be the cause of the boost gauge not working as it should? I have 2 new gauges and I tested both with the same results, but on a side note, with all the playing my truck is running sweet with 0 limp mode and plenty of get up and go, and the egt's are hovering on around 320 at 100kph and climb to around 400 on a hill

[Rickie3]

Also to ask the pipe that runs from the IC back to the turbo, is this right pipe to use for the boost gauge?

[Sir Roofy]

on which end? It seems the dawes is doing its job though as you can limit your boost....



On the highway i run 15psi...

ok but you have more air going in so that would allow you moreboost

[mudski]

Rickie. If you have a boost leak, which it does look like you do, you will struggle to get boost pressure via the dawes. As for boost fitting placement. Anywhere from the turbo right around to the intake is fine mate.

[Rickie3]

Ok still waiting to get things done, sent my IC in to get the tanks welded and that ended up a mess, so waiting on a brand new one to arrive, anyway decided to have a play with the dawes valve, removed from car, and thought I would get a rough setting of around 15psi using my compressor, so hooked up dawes adjusted the psi on the compressor reg to around 17 psi, and kept adjusting dawes till I could just hear air escaping, had a spare boost gauge and hooked that onto dawes valve sqeezed the trigger and was rather happy to see gauge just pop over 15psi, I think this is probably a good start to get you in and around a ball park area of settings, once my truck is going again it will just be a matter of fine tuning the dawes

[Rickie3]

new IC showed up, got big girl up and running, well must say setting up dawes using the compressor was a success near spot on, just a little tweek more to 17psi and she's spot on, pyro reads on steep hill a frag over 400, sits a bit below 200 cruising, so pretty happy with that

[Otech66]

Hi guys, I imagine this dawes valve Rickie3 is playing with is a valve that bleeds off boost to the wastegate control to allow the wastegate to open later?
I am sorry if i sound uneducated. Can someone correct me if I'm wrong.
Regards Otech66

[Rickie3]

I'm getting a strange thing happening when it hits 10 psi, its like a blow off valve type feeling and the boost drops, and a sort of pig rooting effect, think I might have to re-do all my settings from scratch, also occasionally hitting limp mode, personally starting to think this dawes valve is too much stuffing about to get it right, stopping and starting lifting bonnet on the side of the road to make adjustments is crazy, surely there has to be a more effective system for these engines than having to dick around doing this

[93patrol]

Yep get a diesel mech to do it for you haha.

[Rickie3]

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?

[Rumcajs]

Hi guys, I imagine this dawes valve Rickie3 is playing with is a valve that bleeds off boost to the wastegate control to allow the wastegate to open later?
I am sorry if i sound uneducated. Can someone correct me if I'm wrong.
Regards 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.
http://www.nissanpatrol.com.au/forums/images/imported/2014/04/1.gif

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.


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?

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

[Rickie3]

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.

Cheersno 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

[Rumcajs]

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

[Rickie3]

Yes have needle valve installed as well also EGR blanked

[mudski]

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.