TB Coolant line bypass for an NA... Question!

[Trimble Epic]

Can someone clarify what is needed for the coolant line bipass mod on an NA?

I was reading the wiki here: http://z32.wikispaces.com/Coolant+Line+ ... %20Routing

and it says at the bottom to just "cap off the water lines with rubber bypass caps."

So, do I need any hose? I kind of expected to need something, but now I'm not sure what.

Help?

Even if someone could point me to a post/article/video of someone doing the bypass on an NA and discusses the new parts needed...

[itsa300zx]

Do you see the smaller hose nipples(6 or 8 mm) on each of the heater core tube?
Just connect the two nipples from one to the other with a hose and clamps, OR cap them off.

[ThisIsSparTTa]

For an NA, they don't need to be routed anywhere now. You can either get some heater core bypass caps, or route them to each other with a short piece of hose.

[Trimble Epic]

What about the vacuum lines that also ride along in the galleries that I'm removing? I think there's an EGR line on the PS and something that goes all the way over to the balance tube on the DS...

I hope I can reach to put the hoses on after the @#$% plenum is off.

[ThisIsSparTTa]

There's no vacuum lines on the underside, should all be water. Check z32.wikispaces.com vacuum diagrams to verify yours.

[Trimble Epic]

Yay! The plenum is off! and wow, I found some missing bolts under it... one missing original bolt from the balance tube, and at least one coil pack bolt(green below) (actually might both be coil pack bolts - two of the coil pack bolts are different... Suspect someone swapped them..) Also, some misc trash, who knows how long it's been... part of a coil pack connector (yellow), probably part of harness holder (blue)



Anyway, that was a b****... NOW I understand why we all do the TB coolant bypass. Add me to the list.



So, I guess I can do rubber bypass caps here (three red above) more trash laying around (yellow). The fourth cap goes over on the Driver side... NOT looking forward to getting to that one...

Ok, after some pondering over the photos in the Wiki, it's now clear what to do with the two vacuum lines. I think I'll just leave the hidden gallery on the underside of the driver's side of the plenum in place and just use it for the vacuum hardline to the carbon canister. I'll need to run a new line for the EGR on the passenger side though. I actually broke the EGR vacuum line(green above), I didn't realize it was part of the PS coolant line gallery. I'll have to replace that line. (@#$% getting to the EGR valve nipple doesn't look like fun...)

Then again, Now that my plenum is off and I examine the EGR system... mine is COMPLETELY clogged. it looks like this on both sides.

So, basically I've been running without EGR since I got the car. I'm wondering what affect that has on the performance, if the ECU thinks it's working... (then again, the ECU adjusts itself based on the O2 sensor, right?) I'm pondering doing the partial delete to at least closeup the plenum, but I'm not sure if that's really the way to go. I really don't want to try to FIX the EGR, as I really don't want to have to dig down to the EGR valve on the back of the engine... but, if I don't delete it, I'll at least have to get a new vacuum line down there... (unless I junction the existing line that used to connect under the plenum.. hmm.. that WOULD be easier by FAR... I think I'll just do that.

So, this whole job is happening because I found an injector that ohm's at 33 ohms... (111 ohms when I rechecked...) I ordered a set of injectors from that seller on eBay (TLFperformanceparts). They look good, and seem to have included the o-rings... At least, I'm assuming they are new o-rings... if anyone else has used these guys, is it safe to assume the o-rings are new? I ordered a set from Z1 already, so I can change them if I need to... I only needed one, but I got 6 and I'm wondering if I should replace them all with the new set (TLS says they are "flow matched"?) Anyway, once the plenum was off, I found this:

So, I guess it's back to the ordering page at Z1 heh... but I need to decide what I'm doing with those EGR tubes... new gaskets? or blocking plates? Not sure which way to go yet. I'd love some commentary on that. Oh, and I think I'll order a new PTU connector kit; I have the subharness and it's ugly. It's not causing any issues yet, but since I disturbed it for this work... who knows.

Anyway, now that I have some photos uploaded, I need to go back and add photos to my other posts.. hahaha broken promises need to be fixed.


EDIT - whoops, I intended to add this reply to my OTHER thread. Sorry 'bout that...

[Trimble Epic]

There's no vacuum lines on the underside, should all be water. Check z32.wikispaces.com vacuum diagrams to verify yours.

Sorry, sir, but these two I've outlined are most certainly vacuum lines.

This one connects the balance tube to the carbon canister, if I understand correctly. I'm going to leave this gallery on just for that tube. I might cut off the water lines and leave just that tube...


This one connects the EGR valve to the EGR solenoid... This is the hose I broke. It would be a PITA to reconnect this during reinstall of the plenum, so I think I'll remove that one and just run a hose directly, probably adding a junction to the existing torn vacuum line so that I don't have to dig out the EGR. (pending decision on dealing with EGR :P )


oh that disgusting EGR.. what to do.. what to do...

[ThisIsSparTTa]

Just use the vacuum diagram to run the hose directly without the intermediary metal piece then. It's just adding complexity and more places to leak.

[Trimble Epic]

I agree on the passenger side hardline... that s***'s gone.

I'm leaving on the driver's side gallery just for that one vacuum line though. I disagree with your thought that it's adding complexity... I would want to find a way to secure and "tidy up" a vacuum line that ran up onto the balance tube... clips? bracket? dunno... Leaving it in means less flexibly stuff to look at.

My main criteria for this decision is this: When I put the plenum back on, and then take off again in the future, how hard will it be to deal with that vacuum line? For the passenger side, reattaching or removing the EGR tube to the hardline under the back of the plenum = hell no, don't wanna deal with it. For the driver's side, reattaching and removing those two bits of vacuum line? bah, trivial. Don't have to deal with it until final button up.

I still might go ahead and grind off the water lines so that the gallery is JUST for that one hardline.

[RubyRed300ZX]

You may already be aware of the benefit for the EGR system; but, I'll post anyway. EGR is the exhaust gas recirculation system. It has no no noticeable effect on performance unless perhaps you're running a 1/4 mile with trap lights. Its purpose is fuel economy. Back in the 70's when it was introduced, it did cause a loss of performance. Now with fuel injection and a engine-computer-management, there is no noticeable loss of power for the typical driver. The EGR valve is operated by engine vacuum. It recirculates exhaust gas back into the cylinders. The exhaust gas is inert (no oxygen). How much exhaust gas is determined by each engine developer. For the sake of clarity here, lets say on the 300ZX it's 1/3 of the total air intake. Because the exhaust gas is inert, the computer by use of the O2 sensors adjusts the fuel flow into the cylinders by 1/3 when the EGR system is operating. As a result, when you are idling or cruising at a steady highway slog, the addition of the exhaust gas effectively reduces the combustion process for each cylinder by 1/3. Effectively reducing the total displacement by an equal amount. If we use the presumed 1/3 factor, then when you are idling or at a steady highway slog speed, you are in essence driving with a 2 Liter engine instead of 3 Liters. When you put your foot into the gas pedal, the resulting vacuum pressure nearly instantly deactivates the EGR system.

I have mine intact for this very reason ... fuel economy and virtually no loss of performance.

[Trimble Epic]

...Its purpose is fuel economy. Back in the 70's when it was introduced, it did cause a loss of performance. Now with fuel injection and a engine-computer-management, there is no noticeable loss of power for the typical driver. The EGR valve is operated by engine vacuum. It recirculates exhaust gas back into the cylinders. The exhaust gas is inert (no oxygen). How much exhaust gas is determined by each engine developer. For the sake of clarity here, lets say on the 300ZX it's 1/3 of the total air intake. Because the exhaust gas is inert, the computer by use of the O2 sensors adjusts the fuel flow into the cylinders by 1/3 when the EGR system is operating. As a result, when you are idling or cruising at a steady highway slog, the addition of the exhaust gas effectively reduces the combustion process for each cylinder by 1/3. Effectively reducing the total displacement by an equal amount. If we use the presumed 1/3 factor, then when you are idling or at a steady highway slog speed, you are in essence driving with a 2 Liter engine instead of 3 Liters. When you put your foot into the gas pedal, the resulting vacuum pressure nearly instantly deactivates the EGR system.

I have mine intact for this very reason ... fuel economy and virtually no loss of performance.

This.

This is what my theory was, and I was hoping that would be the case ... the inert gas effectively reduces our displacement, allowing us to use less fuel at cruising speeds... (see Robo's take on it here)

I would love to know if we can quantify the exact effect on fuel savings... perhaps if someone were to make the same run (long distance drive) with the EGR enabled and disabled and check fuel consumption... (correct me if I'm wrong, but we could disable EGR by simply cutting off it's vacuum feed? or unplug the solenoid? The ECU would not need to be retuned because the O2 sensors control the mix anyway, right?)

I think if I can save some gas, I might want to keep my EGR going. I just need to clean mine out then... sigh.

[Trimble Epic]

Update!

Ok, I've got some time to work on the car today. But first, I thought I would share some photos from the last round.

So, first, I want to show what I've done for my NA TB coolant line bypass, and ask if anyone sees any problems with this.

Here's the first three bypass caps.


Here's a closeup of the third.


Here's the fourth down under the @$#% PCV outlet.


Anyone see any problems with this? Did I miss one? Now's the time to make changes if I've done it wrong.

BTW, I wanted to use the spring clamps that came off with the bypass job, but the bypass caps are too small. Should I be worried about that?

Also, I thought I would share these photos.. After I pulled out the fuel rail, I found the shrapnel of the previous owner's injector replacement. He took it to a shop to have it done...





I guess the shop tried to pull the injector out with pliars and it exploded? Oh yeah, and then there was this:

I may have posted that photo before already, but there it is again. How do you even DO that??!?

On with the fun today!

[Trimble Epic]

Job is complete, these bypass caps seem to have worked just fine for my NA. 4 caps and 4 clamps. No leaks. Drove the car today and checked and rechecked. Coolant is fine. Yay.