This is The Bomb ... with Turbo!

SD diesels were widely available in the US in the 1981-86 Datsun/Nissan 720 pickups, and in Canada through '87 in the D21 pickup.

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macorti
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Location:Costa rica

#106

Post by macorti » 11 years ago

Knucklehead wrote:If you look on page 4 (of 7) about halfway down the page, you will see two very clear pictures of the two lines going from the governor. The forward one goes into the underside of the black air box, It doesn't matter where on yours, as long as it is somewhere between the turbo and the TB. It MUST have boost! If it is disconnected, that is your problem. The lines are easy, those two are the only ones that are very important. If the vent line has boost as it should, when you close the throttle the extra pressure will PUSH the diaphragm back closed. A torn diaphragm is not the problem or it would never run normally N/A..

I was only speaking about atmospheric pressure hypothetically. (Supongamos que la presion del ambiente era doble, que seria diferente? Nada.)
Hi KH,

Talking about the vent line, it think it was connected as I said into the air box, but what it's not clear to me is that it was not between the TB and the turbo as you said it has to be plugged. The order goes like this:

1- Air Box (vent line)
2- Turbo
X- IC
3- TB

So, this vent line had no boost cause it was before the turbo right?

What happens it's that comparing your truck's configuration with mine there's a difference in regards the order, TB position and hence the intake.

You can look at it better in the following pic.

Image

Note: if you need more pics or data in order to clear things out, please don't hesitate in letting me know, I will get them right away, well when I'll get home after work.
Macorti TD42

Tracteur Tom
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Joined:12 years ago
Location:France

#107

Post by Tracteur Tom » 11 years ago

Hi Marco,

The "vent" line needs to see boost pressure, ahead of or before the "vac" line (the one that connects to the venturi). So from what you are saying it appears that this is wrong as it is seeing the air flow though the improvised air filter and not boost pressure. In the original set-up the air filter was bolted to the TB and hence thats why we say the vent line should connect to the air filter. But for the turbo it needs to be moved. If this is not clear post again and I'll try to explain in a bit more detail.

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Knucklehead
Posts:148
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Location:Phoenix

#108

Post by Knucklehead » 11 years ago

It is clear in our heads. The engine may be different from mine, but if the governor uses a diaphragm, the vent line cannot go to the air cleaner (1). Best would be between the intercooler and the throttle body, if you use the intercooler again.
1. Air cleaner
2. Turbo
x. Intercooler
<<<!! - Put the vent line here!!
3. Throttle body
'82 standard cab 3 axle SD22 turbo
'89 int'l 9700 Cummins 444 (855 ci)
'29 HD FD export model

macorti
Posts:16
Joined:11 years ago
Location:Costa rica

#109

Post by macorti » 11 years ago

Tracteur Tom wrote:Hi Marco,

The "vent" line needs to see boost pressure, ahead of or before the "vac" line (the one that connects to the venturi). So from what you are saying it appears that this is wrong as it is seeing the air flow though the improvised air filter and not boost pressure. In the original set-up the air filter was bolted to the TB and hence thats why we say the vent line should connect to the air filter. But for the turbo it needs to be moved. If this is not clear post again and I'll try to explain in a bit more detail.
Hi TT,

Thanks for your explanation, it's clear to me now. And yes, for what a remember this line was never plugged between turbo and TB, but now I have another doubt, do you guys think that this wrong connection made the car rev by it self?
Macorti TD42

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Knucklehead
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Location:Phoenix

#110

Post by Knucklehead » 11 years ago

Absolutely!
'82 standard cab 3 axle SD22 turbo
'89 int'l 9700 Cummins 444 (855 ci)
'29 HD FD export model

macorti
Posts:16
Joined:11 years ago
Location:Costa rica

#111

Post by macorti » 11 years ago

Knucklehead wrote:It is clear in our heads. The engine may be different from mine, but if the governor uses a diaphragm, the vent line cannot go to the air cleaner (1). Best would be between the intercooler and the throttle body, if you use the intercooler again.
1. Air cleaner
2. Turbo
x. Intercooler
<<<!! - Put the vent line here!!
3. Throttle body
Hi KH,

I'm now clear with your explanations, and I also watched what you said about having this vent line in the wrong place, but can you explain me what happens inside the pump with this wrong connection and also can you go deeper in regards what weird effects can happen as TT said.
Sorry if I'm asking to much, what happens it's that I like to learn all I can, this is very very interesting.
Macorti TD42

Tracteur Tom
Posts:11
Joined:12 years ago
Location:France

#112

Post by Tracteur Tom » 11 years ago

Hi Marco,

To be honest, the best way to get your head around how it works is to read the posts on this Forum. There is some brilliant stuff.

To put it simply - very - the diaphragm is held in suspension between the 2 chambers that connect to the vac and vent lines. Connected to the diaphragm is the rack that rotates the plunger barrels and therefore controls the fueling. By moving the diaphragm one way or another will control the amount of fuel that is available for injection. Next bit to get your mind around is the venturi and throttle plate. This is there to create a pressure differential (PD) and the 2 air lines need to connect to either side of this venturi to make use of the pressure differential. Now when on WOT, the PD is 0 and the diaphragm moves to the max fuel position under the weight of the smoke screw. As the throttle is moved away from WOT, a PD is developed that moves the diaphragm and in turn reduces the fuel delivery. When the throttle plate is shut, max PD is developed and the rack is pulled all the way back to its set idle position.

As you can hopefully see, the PD is key and its got to come from the venturi. Whether the i/p air pressure is atmospheric or lifted by some amount with a turbo, the signal has got to balance the diaphragm.

Hope that helps

Phil.

macorti
Posts:16
Joined:11 years ago
Location:Costa rica

#113

Post by macorti » 11 years ago

Tracteur Tom wrote:Hi Marco,

To be honest, the best way to get your head around how it works is to read the posts on this Forum. There is some brilliant stuff.

To put it simply - very - the diaphragm is held in suspension between the 2 chambers that connect to the vac and vent lines. Connected to the diaphragm is the rack that rotates the plunger barrels and therefore controls the fueling. By moving the diaphragm one way or another will control the amount of fuel that is available for injection. Next bit to get your mind around is the venturi and throttle plate. This is there to create a pressure differential (PD) and the 2 air lines need to connect to either side of this venturi to make use of the pressure differential. Now when on WOT, the PD is 0 and the diaphragm moves to the max fuel position under the weight of the smoke screw. As the throttle is moved away from WOT, a PD is developed that moves the diaphragm and in turn reduces the fuel delivery. When the throttle plate is shut, max PD is developed and the rack is pulled all the way back to its set idle position.

As you can hopefully see, the PD is key and its got to come from the venturi. Whether the i/p air pressure is atmospheric or lifted by some amount with a turbo, the signal has got to balance the diaphragm.

Hope that helps

Phil.
Hey Phil,

Wow thanks a lot for the explanation again, I see now why this lines are so vital for the good functioning.
Something that I been thinking about is if the oil that goes out from the turbo into the inlet will cause some damage. As you know that's an issue that occurs with this TB systems when they get turboed. I heard a guy in Patrol4x4 saying that he had his MK running like that since 3 years ago and he didn't have any dramas, but I think it wouldn't be normal for the engine, I think that for the short or mid term it will cause a lot of obstructions.
Macorti TD42

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Knucklehead
Posts:148
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Location:Phoenix

#114

Post by Knucklehead » 11 years ago

There are some pictures about how the diaphragm works here.

Unless your turbo needs to be rebuilt, it should not leak that much oil if you have it before the TB. The TB only becomes a problem if it comes before the turbo, but we have established that configuration is not the best anyway. Too much oil causes carbon buildup in the head and pistons.
'82 standard cab 3 axle SD22 turbo
'89 int'l 9700 Cummins 444 (855 ci)
'29 HD FD export model

macorti
Posts:16
Joined:11 years ago
Location:Costa rica

#115

Post by macorti » 11 years ago

Knucklehead wrote:There are some pictures about how the diaphragm works here.

Unless your turbo needs to be rebuilt, it should not leak that much oil if you have it before the TB. The TB only becomes a problem if it comes before the turbo, but we have established that configuration is not the best anyway. Too much oil causes carbon buildup in the head and pistons.
So you think that this amount of oil been sucked from the turbo will cause no harm to the engine?

Oh ok, I'm concern about this cause on 2 road test that the lab guys and I made to GQ, the pipes came off from the IC and some oil came off the pipes. The turbo was a brand new KKK (k16). So I don't think it was the turbo.
When we unbolt everything I took the IC and I flipped it and some oil came out from it.
Macorti TD42

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Knucklehead
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#116

Post by Knucklehead » 11 years ago

Mine is the same way, and I pass the emissions test at zero of twenty when running on biodiesel. No, I do not think it is a problem. And yes, it is from the turbo.
'82 standard cab 3 axle SD22 turbo
'89 int'l 9700 Cummins 444 (855 ci)
'29 HD FD export model

macorti
Posts:16
Joined:11 years ago
Location:Costa rica

#117

Post by macorti » 11 years ago

Knucklehead wrote:Mine is the same way, and I pass the emissions test at zero of twenty when running on biodiesel. No, I do not think it is a problem. And yes, it is from the turbo.
Ok excellent thanks KH, when I said I didn't think it was the turbo I meant that the turbo was working fine, but definitely it was coming from the turbo.

I was reading one of your post (page 4 I guess) on Tuesday night and you mentioned that you would like to remove the TB in order to have your system working at the way you want it, so, do you still want to do that or you did it already?

Do you think that in order to get a good result it's vital to remove it?

Cause I don't want a race car, I just want to get my GQ to go better and have a good response, specially going up hills, so in my case will it be a most?
Macorti TD42

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Knucklehead
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Location:Phoenix

#118

Post by Knucklehead » 11 years ago

I have always said that the TB needs to go. Even without a turbo it should go. I haven't changed mine yet. I have an ex-sister in law who had a 4 mo old die from crib death in her care and the state is trying to give her the death penalty. I sold my house to help her, so I haven't had any time or money. Waah waah.

Originally I thought the TB made very little restriction, but I was wrong. The restriction is small when N/A, but with a turbo it is multiplied.
'82 standard cab 3 axle SD22 turbo
'89 int'l 9700 Cummins 444 (855 ci)
'29 HD FD export model

macorti
Posts:16
Joined:11 years ago
Location:Costa rica

#119

Post by macorti » 11 years ago

Knucklehead wrote:I have always said that the TB needs to go. Even without a turbo it should go. I haven't changed mine yet. I have an ex-sister in law who had a 4 mo old die from crib death in her care and the state is trying to give her the death penalty. I sold my house to help her, so I haven't had any time or money. Waah waah.

Originally I thought the TB made very little restriction, but I was wrong. The restriction is small when N/A, but with a turbo it is multiplied.
Oh man I'm sorry to hear that, I hope everything will be fine for all of you...

As your own criteria or opinion, what has to be done in order to remove the TB, what options are on the table to do that?
Macorti TD42

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Knucklehead
Posts:148
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Location:Phoenix

#120

Post by Knucklehead » 11 years ago

Either:
1.) Get the RLD governor from the turbocharged SD33T which will fit the pump perfectly,
2.) Get the RSV governor from a forklift model and modify it,
3.) Adapt a rotary pump from an SD25 (or any other pump for that matter)
4.) Modify the existing RBD-MZ governor to to be mechanical.
'82 standard cab 3 axle SD22 turbo
'89 int'l 9700 Cummins 444 (855 ci)
'29 HD FD export model

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