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First post on here, and I dont like jumping in just for info. So here is a bit of background.
I was working in Bougainville as a Stock Inspector back in the 70,s when I found this Forward Control Land Rover down the bottom end near Buin.
My wife and I rescued it for a slab of SP beer and towed it back to Kieta on an A frame behind my old diesel wagon.

We got the 6 cyl going and used it for work then when I finished my contract in 1980 we took it to NZ. NZ did not work out so we moved to the Sunshine Coast in Qld
Australia. There I fitted a Perkins 6-247 and used it towing a skidsteer on a semi trailer.
In the 90,s I gave it a refit with a 4BD1 and an LT95 gearbox. I also fitted Salisbury axles front and back with Maxidrive difflocks. and a camper back.

Tried for pics but I cant on first post. So more later.
 

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Discussion Starter #2
Woops. Where is the edit button? I meant Salisbury axles fitted as I broke an ENV diff

Found it. The ENV diffs are weak because of the little pinion bearing so I swapped for the Salisbury and increased the track 4 inches at the same time.
 

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Welcome to the forum! Although I'm just coming off of 4 year hiatus, it seems this board isn't quite as active as it used to be.

Anyway, very cool trucks and a little jealous that we don't have many like these in the US. As for your setup, the HX30 is perfectly sized for your engine and the SS tees you used should be sufficiently adequate. Large quantities of black smoke indicate an over fueling condition which is either too much fuel or not enough boost. I'm assuming the engine worked fine before adding the turbo and therefore the timing has not changed. How much boost are you getting, if any, at the moment? Is the turbo spinning at all? I can get several pounds of boost at 2000 rpms (in neutral) with my TD04hl-13T which isn't that much different than you HX30. I would also tap into the wastegate pressure line and run a second, more sensitive gauge (0-15 psi) that is taped to the windshield so it is easier to see while driving. You should be able to get 10+ psi of boost from your engine with little trouble. If no boost, then the problem is likely with the turbo or possibly the wastegate opening way too early. If you put a pressure regulator to the wastegate, at what pressure does it start to open. If you want 10 psi of boost, the wastegate should not start to open until roughly around 12-15 psi of boost pressure. This extra pressure from the wastegate canister is necessary to resist the exhaust backpressure from also trying to open the wastegate.

Adam R.
 

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Discussion Starter #9
Thanks for your reply Adam. I was thinking perhaps I should have made the manifold with a taper somehow getting bigger as it got to the turbo. I am pleased you think its OK. I was going to unbolt the turbo and see if it still smoked straight out the pipe but I will leave that and try your ideas first. Yes it worked well NA, this has just happened since I put the turbo on.
I have a VDO boost gauge in the intake manifold and its not moving so I will investigate those other options.
I took the hose off the turbo and the thing is spinning.I took the hose off the outlet of the WTA and can feel air coming out but not much, but then I was not revving much either.

Keith
 

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I was reading some stickies. I read about a cold start fuel enrichment thing. Could this be stuck and causing my problem.?
Where is it and what does it look like?
Clutching at straws here.
 

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You need to confirm you are getting boost compressor/turbine wheels spinning is common however if the gate is open or opens too early you will not get any boost to burn that extra fuel.

As enrichment goes anyone who would reply would need to know what IP you have in order to answer that question.
 

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What have you done to the injection pump since fitting the turbo? The 4BD1 (non turbo) doesn't have a boost compensator to limit fuel until the turbo spools up, so black smoke before spoolup is tricky to avoid. The A pumps we have run a fuel plate inside the governor which sets fuel based on rpm. This can be modified to reduce fuel at lower rpm to limit smoke but I haven't tried doing that.

I would look for air intake restriction as the source of your high EGT and black smoke while still in the shed.

For your exhaust manifold. The size is fine, the shapes are awkward as the Isuzu ports are rectangular and the pipes are round. A better design if you keep using pipe fittings is to use elbows exiting each port and trim them into the manifold tube so all the pulses are pointed in the exit direction. Sort of like a row of r's. rrrrr

Are you the same Keith from AULRO who once lived in my home town?
 

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Just for comparison sake, if I rev my engine to around 2000 rpms without any turbo to intercooler tubing in place, the amount of air coming out of the turbo compressor is comparable to an electric leaf blower. It won't build much more than 2-3 psi with the tubing in place and no load, but it is still obvious that the turbo is working and pushing lots of air.

Adam
 

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Discussion Starter #15
What have you done to the injection pump since fitting the turbo? The 4BD1 (non turbo) doesn't have a boost compensator to limit fuel until the turbo spools up, so black smoke before spoolup is tricky to avoid. The A pumps we have run a fuel plate inside the governor which sets fuel based on rpm. This can be modified to reduce fuel at lower rpm to limit smoke but I haven't tried doing that.

I would look for air intake restriction as the source of your high EGT and black smoke while still in the shed.

For your exhaust manifold. The size is fine, the shapes are awkward as the Isuzu ports are rectangular and the pipes are round. A better design if you keep using pipe fittings is to use elbows exiting each port and trim them into the manifold tube so all the pulses are pointed in the exit direction. Sort of like a row of r's. rrrrr

Are you the same Keith from AULRO who once lived in my home town?
Hi Dougal, I was hoping you would see this. You have a good memory:). Yes it is I.
All I did to the pump when I bolted stuff up was to open the fuel screw one turn. Then when all this happened I screwed it back in again but of course no difference.. I looked for intake restriction by taking that hose off between the intercooler and manifold but it still smoked and got high EGT,s. Perhaps a rat or snake got into the manifold before I got the hoses on. I guess I better pull it all to bits again though I cant smell anything dead.
I cant do much now as my wife fell and broke a couple of ribs so I am hospital visiting every day untill she is out.
Another thing. This inlet manifold has springs under the heads of the fixing bolts. My other one does not. What is that about?
Keith
 

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Discussion Starter #16
Came home early today to have another play.
Took off the pipe from inlet manifold to outlet of IC.
Started up and revved to 2500 odd EGT went up to 500C odd and still black smoke. I cant see any obstruction in inlet and its got good suck when holding hand over the pipe.
However, revving up and holding my palm over the IC outlet its easy to block it off and the wastegate rod does not move.
I would have thought 10 pounds or so would be harder to stop and if it was getting 10 pounds would not the wastegate rod start to move. I am still thinking manifold or something wrong with the turbo.
Thoughts?
Keith
 

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Discussion Starter #17
Correction. Just had another think. I would not be getting boost anyway as I am still just revving in the shed. So as Adam said its only 2 or 3 pounds so thats probably right.
I guess next step is to pull the exhaust from the turbo and see what happens. I cant see how it would be over fuelling.
 

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Came home early today to have another play.
Took off the pipe from inlet manifold to outlet of IC.
Started up and revved to 2500 odd EGT went up to 500C odd and still black smoke. I cant see any obstruction in inlet and its got good suck when holding hand over the pipe.
However, revving up and holding my palm over the IC outlet its easy to block it off and the wastegate rod does not move.
I would have thought 10 pounds or so would be harder to stop and if it was getting 10 pounds would not the wastegate rod start to move. I am still thinking manifold or something wrong with the turbo.
Thoughts?
Keith
Does sound like something is up in the exhaust side. Time for some exploratory surgery I think.
 

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Discussion Starter #20
FOUND IT1111111
Pulled off the dump pipe to see if it smoked without it, looked down and there was the bloody exhaust brake shut.
I had looked at it previously, checked it with the engine going and it moved OK and did not seem to make much difference at a fast idle so ignored it. But here it is shut. I must have put the pipes on the wrong way around. They are both the same colour, black, so too easy. Swapped them around , no smoke and low EGT..
I will blame the onset of oldtimers disease. I was 74 a couple of months ago so that will do
So thats a lesson, a blocked or restricted exhaust can cause those symptoms.
I will take it for a burn up and down the drive next, see how it behaves before a road test.

turbo install.03 by https://www.flickr.com/photos/141809
 
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