TD42 Losing boost pressure

So I took the Patrol out over the weekend to grab a few things at the shops and also give it a bit of a run. I did notice I can't make no more than 20psi boost pressure when I could easily make 30, and she's blowing more black smoke than usual (so it seems, might just be me on that bit).

So I've removed all silicone boost hoses cleaned and inspected them and decided I will change them out anyway. Intercooler looks spot on, and all hoses from the manifold to Injector pump and then to the boost controller are good. I will try to get a hold of another boost gauge just incase mine is playing up

If changing out the hoses doesn't work, and the boost gauge is reading right, what else should I be looking for? .

Cheers.

Checked the boost controller ???
That's what played up on mine last year.

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Originally Posted by Hodge

Checked the boost controller ???
That's what played up on mine last year.

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I might remove it and clean it out. Might just be full of oily gunk. Been on there for nearly five years now and never been touched. Cheers.

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Originally Posted by Hodge

Checked the boost controller ???
That's what played up on mine last year.

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My friend is looking to get this TD42 with an intermittent boost pressure issue. We'll just finish installing the brake kit and g2 axle & gear on the Jeep this week before we can check the TD42 boost controller and hoses.

Update.

My Patrol is just sitting here. Lol.
Boost controller is fine, so are all the hoses and the IC is fine. Changed out the fuel filter and it didn't help. Theres no gauze screen on the inlet line going into the pump. So its either the motor or injector pump. I assume. In lockdown so no rush.

Are you down on power? Suction side of turbo is all good? Air filter not clogged? Snorkel is open and free?

….anyone say Y62[emoji23]


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Originally Posted by nissannewby

Are you down on power? Suction side of turbo is all good? Air filter not clogged? Snorkel is open and free?

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Yes.... Pretty sure it is, hard to tell. The whistling sounds of the Garret have not changed tone one bit.... Air filter is fresh.... I haven't checked the snorkel. I will look at the entire intake, from snorkel head to turbo intake over the weekend. EGT's are slightly up too.

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Originally Posted by Maxhead

….anyone say Y62[emoji23]


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I'm working on that. Slowly.

Been locked down too long. Taking it for a drive and absolutely sink it. She'll boost in no time I reckon. lol

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Originally Posted by Hodge

Been locked down too long. Taking it for a drive and absolutely sink it. She'll boost in no time I reckon. lol

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Haha tried that.

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Originally Posted by Maxhead

….anyone say Y62[emoji23]


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Me! Me! Me! It was Me!......

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Originally Posted by mudski

Update.

My Patrol is just sitting here. Lol.
Boost controller is fine, so are all the hoses and the IC is fine. Changed out the fuel filter and it didn't help. Theres no gauze screen on the inlet line going into the pump. So its either the motor or injector pump. I assume. In lockdown so no rush.

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I would say yoy have a boost leak for sure. That explains the lack of boost and the black smoke as it is tuned for more boost so over feeling now. I woyld be tracing every boost hose looking for a split or blown hose . You may fine it just with the bonnet up and someone revving up the car.

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Originally Posted by MudRunnerTD

I would say yoy have a boost leak for sure. That explains the lack of boost and the black smoke as it is tuned for more boost so over feeling now. I woyld be tracing every boost hose looking for a split or blown hose . You may fine it just with the bonnet up and someone revving up the car.

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Already done this mate. Replaced every boost hose in there now. The only thing I haven't checked is the intercooler. But being a barely used Cross country Ic I doubt its the cause. I will look more into a few things when the weather warms up.

Big Stogie Cigar trick possibly Mark Mate[emoji106][emoji106]
Smoker or not, fill your cheeks with a massive cloudy gob full and pressure witness visually test that aluminium radiator thingy [emoji23]


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Have you taken a reading directly from the compressor with the wastegate firmly closed?

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Originally Posted by jff45

Have you taken a reading directly from the compressor with the wastegate firmly closed?

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No. How do I do that?

Connect the gauge hose directly to the compressor housing outlet and remove the hose on the wastegate actuator.
Don’t go silly with it in case it boosts high before it overcomes the actuator spring

The compressor outlet will currently be connected to your boost controller which then feeds back to the actuator.
I assume your gauge hose is connected to your IC or manifold?

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Originally Posted by jff45

Connect the gauge hose directly to the compressor housing outlet and remove the hose on the wastegate actuator.
Don’t go silly with it in case it boosts high before it overcomes the actuator spring

The compressor outlet will currently be connected to your boost controller which then feeds back to the actuator.
I assume your gauge hose is connected to your IC or manifold?

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Yes my gauge reads from a port in the inlet manifold. Then another port T'd (one to the injector pump, one toward the boost controller), then to another T, (one to the boost controller and the other to the wastegate actuator) Apparently its plumbed like this for high boost applications.

So what should i see doing as you suggest John? What shouldn't I be seeing?

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Originally Posted by mudski

Yes my gauge reads from a port in the inlet manifold. Then another port T'd (one to the injector pump, one toward the boost controller), then to another T, (one to the boost controller and the other to the wastegate actuator) Apparently its plumbed like this for high boost applications.

So what should i see doing as you suggest John? What shouldn't I be seeing?

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You will be taking out the intercooler. straight off the actuator will show you the boost output at the turbo

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Originally Posted by MudRunnerTD

You will be taking out the intercooler. straight off the actuator will show you the boost output at the turbo

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Ahh ok.

I don't have a boost port pre intercooler though. Or am I missing something?

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Originally Posted by mudski

Ahh ok.

I don't have a boost port pre intercooler though. Or am I missing something?

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yeah the hose nipple at the actuator is pre intercooler.

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Originally Posted by MudRunnerTD

yeah the hose nipple at the actuator is pre intercooler.

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Hmm.
Right. This is something I've never played with so its all new to me. So all Im doing is removing the boost hose from the controller to actuator? Go for a spin and see what I get in boost pressure?

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Originally Posted by mudski

Hmm.
Right. This is something I've never played with so its all new to me. So all Im doing is removing the boost hose from the controller to actuator? Go for a spin and see what I get in boost pressure?

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Not quite. What I’m suggesting is to read the boost that’s coming directly from the turbo to eliminate any issue with the wastegate.

On the turbo compressor housing there will be a barb where the boost pressure is sent to the entry side of your boost controller. Something like the brass barb on my P4x4:

Attachment 84290

You need to take the hose from your IC, or wherever the boost gauge gets its reading, and connect it directly to that barb so the gauge reads the boost the turbo is making. You’ll almost certainly have to lengthen it to reach.
That should completely isolate your boost controller and the boost will have no effect on the actuator.

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Originally Posted by jff45

Not quite. What I’m suggesting is to read the boost that’s coming directly from the turbo to eliminate any issue with the wastegate.

On the turbo compressor housing there will be a barb where the boost pressure is sent to the entry side of your boost controller. Something like the brass barb on my P4x4:

Attachment 84290

You need to take the hose from your IC, or wherever the boost gauge gets its reading, and connect it directly to that barb so the gauge reads the boost the turbo is making. You’ll almost certainly have to lengthen it to reach.
That should completely isolate your boost controller and the boost will have no effect on the actuator.

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My Turbo doesn't have that barb as per pic.

Ok, in fact, if you have a boost leak in the system then it will be down on boost anyway.

I spoke with a customer yesterday who's a TD nut and he told me to use my air compressor and run 5psi and then in 5 psi increments directly into the actuator to see if it moves and when, as he said its likely either the actuator is kaput or even the wastegate springs have broken. So I'll attempt this over the weekend.

That's why I was suggesting testing boost directly with the wastegate firmly shut. If the spring is broken inside the actuator, although I've never heard of that on any forum, you should be able to just feel the loose actuator rod with your fingers.

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Originally Posted by jff45

That's why I was suggesting testing boost directly with the wastegate firmly shut. If the spring is broken inside the actuator, although I've never heard of that on any forum, you should be able to just feel the loose actuator rod with your fingers.

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Ahh ok. I wasn't sure what you were actually trying to find with this. Makes sense now. Sorta. i've never had to dabble in this part of the TD's so its all new to me.

Update. So I clamped the boost line shut to the actuator. Took it for a spin and wow! Full boost and she screamed!
Just got to figure out what this means. What part has failed to cause this. The controller is merely a needle valve which restricts air flow. It works. I can wind it right in and it shuts off flow. So I can’t see this being the cause, but who knows.

Atleast I’ve made some progress.


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Winding the boost controller in to shut off flow should be the same result as blocking flow to the actuator. Also same as blocking the inlet side of controller.

So I bought a new boost controller. My existing controller was a "bleed" controller, different to the usual setup, I suppose usually found as "in cab" setups. See pic below.
Attachment 84331

So now I've gone for the conventional setup of an in Line T from Turbosmart and everything works.

To be honest I still am not sure why. As the old controller is simply just a bleed valve, theres no spring and ball setup in the valve, just a needle point the shuts off or allows air flow. I had tried everything else I knew first and this was my last straw before I was to hand the Patrol over to the experts for them to sort it. Now I don't need to.

One thing I have found though, and I'm still unsure why. Now with this new controller, boost comes on earlier than before, maybe circa 500rpm earlier, and off boost soot is way less than before. Dunno why! Im not gonna argue this. Maybe my on road "cowboy tune" has hit the sweet spot.???

Might even chuck it back on the rollers now for some extra killer wasps!