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	''(if you want to buy any OEM replacement parts seen in this diagram, ''[https://web.archive.org/web/20160918193704/http:/z31.com/fiche/2/l10.gif ''see FICHE DIAGRAM HERE'']'') <link broken>''		''(if you want to buy any OEM replacement parts seen in this diagram, ''[https://dev.z31library.com/external_images/web.archive.org/web/20160918193704/http:/z31.com/fiche/2/l10.gif ''see FICHE DIAGRAM HERE'']'') <link broken>''

	To replace all the applicable engine lines below (INCLUDING all vacuum and coolant lines), you will want to order the following. Just subtract any of the noted lengths/diameters shown below from the total in the "kit" if you are not going to do that part. ALSO NOTE that these lengths are for the REROUTING that I have done on my car. For each length provided below, the hose length is slightly OVERESTIMATED, and then the total is rounded up to the nearest foot. There will be a little left over of each length. Below are the exact lengths measured out for my installation. Since you have to buy by the foot, you should end up with a few extra inches, just in case. If you want to replace the vacuum tank through firewall hose, you will need to add about 6'.		To replace all the applicable engine lines below (INCLUDING all vacuum and coolant lines), you will want to order the following. Just subtract any of the noted lengths/diameters shown below from the total in the "kit" if you are not going to do that part. ALSO NOTE that these lengths are for the REROUTING that I have done on my car. For each length provided below, the hose length is slightly OVERESTIMATED, and then the total is rounded up to the nearest foot. There will be a little left over of each length. Below are the exact lengths measured out for my installation. Since you have to buy by the foot, you should end up with a few extra inches, just in case. If you want to replace the vacuum tank through firewall hose, you will need to add about 6'.

z31p_Z Karma: Forum archive import (z31performance, restructured)

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Forum archive import (z31performance, restructured)

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|op_user=Z_Karma
|op_date=2024-04-02 21:33:56
|post_count=2
|archive_url=/Z31performance_archive/forum/z31-basics/frequently-asked-questions-faqs/546718-thumper300zx-vac-hose-diagram-site.html
}}

'''Z_Karma:''' <small>(2024-04-02 21:33:56)</small>

Thumpers domain expired so here is a copy of his helpful vac hose diagram page, '''(archived from 07/16/2007)''' Z31 Vacuum Lines

''Diagrams & Replacement''

This page includes lists and diagrams of vacuum lines for 86' Turbo (MT). Any differences between models should be minimal, though they will exist (especially as additional control items were added as the years went on). The diagrams should help greatly with vacuum diagnostics. I strongly suggest becoming familiar with this webpage on [https://web.archive.org/web/20160918193704/http:/www.atlanticz.ca/zclub/techtips/vacuum/ VACUUM DIAGNOSTICS] if you have any problems.

Lengths are approximations (all rounded up to nearest inch) based on the hoses routed in my car at the time of measurement. Except for the vacuum pump lines, all the lines that were run in my Z were stock. Upon replacement, I WILL HAVE MODIFIED the length on front gallery lines and A/C lines to minimize length/cost. If you find stock lengths or your modified route lenghts to be different that I have listed, please drop me a note for comparison. Get rid of this crap, and get this crap instead: scribble_hose.jpghoses.jpg

Pictures of silicone vacuum line will replace these pictures once done, and the exact length of those hoses will be shown.

'''86 Turbo Engine Vacuum Lines (w/o A/C or Cruise shown)''

''note: 9/86 Turbo cars also have SURGE TANK system and vacuum lines

diagram.jpg''

''(if you want to buy any OEM replacement parts seen in this diagram, ''[https://web.archive.org/web/20160918193704/http:/z31.com/fiche/2/l10.gif ''see FICHE DIAGRAM HERE'']'') <link broken>''

To replace all the applicable engine lines below (INCLUDING all vacuum and coolant lines), you will want to order the following. Just subtract any of the noted lengths/diameters shown below from the total in the "kit" if you are not going to do that part. ALSO NOTE that these lengths are for the REROUTING that I have done on my car. For each length provided below, the hose length is slightly OVERESTIMATED, and then the total is rounded up to the nearest foot. There will be a little left over of each length. Below are the exact lengths measured out for my installation. Since you have to buy by the foot, you should end up with a few extra inches, just in case. If you want to replace the vacuum tank through firewall hose, you will need to add about 6'.

''Z31 Silicone Vacuum Hose Replacement Kit'' ''FOR 86 Turbo Manual, CA including vacuum controlled emissions devices

YOUR APPLICATION MAY VARY

9/86 Turbo and Newer will have SURGE PUMP vacuum LINES.''

ORDER NEEDED (for modifed lengths shown below) 116" (order 10 feet) of 3mm

165.5" (order 14 feet) of 4mm

103.5" (9 feet) of 6mm

56" (5 feet) of 10 mm

14" (2 feet) of 3/16" Clear Vinyl (HOME DEPOT) ''does not include Vac Tank through Firewall hose or vacuum hoses inside car (A/C Controls)

Vac Tank about 6' from what I've read''

''7" of the 10mm replaces formed brake booster vacuum hose, which you may not want to do. The actual length needed to replace is more likely around 8"'' Since most stores require a mininum order per hose of 10 ft you will likely have to order 10 ft of 6mm and 10 mm. I would suggest ordering 1 extra foot of each hose just in case: EXTRA FOOT ORDER (gives you at least 1 extra foot of each hose) 11 feet of 3mm

15 feet of 4mm

10 feet of 6mm

6 feet of 10mm (may have to order 10 ft) THE LENGTHS and DESCRIPTION of each hose is shown below

[https://web.archive.org/web/20160918193704/http:/www.thumper300zx.com/z31_vacuum/table.htm CLICK HERE] <link broken> FOR MEASUREMENTS ONLY (for PRINTING) INSTALLATION NOTESInstallation is straight forward. Do one line at a time.
The stock hose clamps on the 6mm lines will not be tight on the new 6mm lines. You can either modify or replace the clamps. You might be able to get away without clamps, but I'd use them on the coolant lines.
On the vacuum tank, there are a couple connectors that have "guards" around the nipple. The new 3mm silicone line will not connect because the walls are too thick. You'll need to either modify the width of the hose with an exacto knife or use a small section of old hose with a barrel connector to connect the new line to the system (pictured below) 100_4953.jpg
Be aware that silicone hose can stretch and therefore BALLOON - you may experience boost leaks if the hoses are not well secured.
You ''should not use'' SILICONE hose in high heat, fuel or oil transport, or off oily emissions areas like PCVs and other hoses coming off valve covers.

At Boost Controller.com ''(black, ''''red'''', or ''''blue'''' only)'' you can get the silicone hose kit listed for $59.46 shipped, $46.01 without 10mm items. I ordered mine in the afternoon, got a ship notification the same day, and received it two days later!

If you get the $58 Hose Techniques STARTER KIT ($58 + shipping) you will end up with 8mm hose that you won't use, no 10mm hose, 3.5mm (which I have found a bit loose), and not enough of anything to get the whole job done. If you do decide to buy from Hose Techniques, it's cheaper to buy it by the foot. Since the kit lists over 10 feet per item (except 10mm) you will make out well --- just won't get the extra in the starter kit (cutters and ties). Or if you trust stuff you haven't seen, [https://web.archive.org/web/20160918193704/http:/cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=8032111598&sspagename=ADME:B:AAQ:US:1 go to eBAY] and get a kit that will cover you 4mm and 6mm for about $25. BE WEARY of eBAY KITS, however -- I purchased one once and instead of being silicone hose, it was VINYL. Completely falsely advertised. Make sure the packaging says SILICONE on it.

'''''I measured the A/C control line ID @ 3mm. I bought the HT kit once many years ago and the 3.5 was a bit loose where I used it. If you do your A/C control lines and cruise line, you may want to save yourself some heartache and reroute them. Instead of running them below the vacuum canister, along the framerail, and back to the firewall, consider running them right along the top. You can use a wire loom to make it look decent. You will then have easy access to them in the future. The kit listed above uses the rerouted lengths.'''''

'''''There is some great information (along with detailed pictures) on vacuum lines and A/C Control Fixes:'''''

'''''[http://users2.ev1.net/~jboykin/vaclines.htm http://users2.ev1.net/%7Ejboykin/vaclines.htm]'''''''''' (Vacuum Lines) '''''''New Link''

'''''[http://z31.com/oboard/archives/view.pl?157 http://z31.com/oboard/archives/view.pl?157]'''''''''' (A/C Blows Hot) '''<link broken>'' DRIVER'S SIDE FRONT AIR GALLERY (from front to back)
Inner Diameter

(I.D. mm)
Stock

Length

(inches)
Modified

Length

(1) to FPR Control Valve (bottom)
4 mm
21"
15"

(2) to FPR Control Valve (top)
4 mm
23"
15"

(3) to Manifold
6 mm
20"
19"

(4) to Throttle (right port)
4mm
13.5"
12"

left.jpgright.jpg

(OLD LEFT || NEW RIGHT)

NEW VACUUM LINES: RED = 3mm || BLUE = 6mm || BLACK = 3mm (''AIV 4mm Lines and EGR ALSO BLACK'')

intake_pipe.jpg

(OLD ABOVE || NEW BELOW)

new_intake_pipe.jpg

driver_bucket.jpg

(OLD ABOVE || NEW BELOW)

new_driver_bucket.jpg

LEFT SIDE of FRONT AIR GALLERY
Inner Diameter

(I.D. mm)
Stock

Length

(inches)

(5) to Manifold Front
4 mm
3"

(6) to FPR
4 mm
3"

(7) to Carbon Canister (bottom, left port)
6 mm
14.5"

(8) to Carbon Cansiter (top, left port)
4 mm
16.5"

fpr.jpg pass_carbon.jpg

NO CHANGE on FPR || Carbon Canister (OLD ABOVE || NEW BELOW)

new_pass_carbon.jpg REMAINING ENGINE CONTROL HOSES
Inner Diameter

(I.D. mm)
Stock

Length

(inches)

(9) EGR Control to EGR
4 mm
5"

(10) EGR Control Valve to Rear Gallery (pass)
4 mm
2.5"

(11) 'TEE' to Boost Sensor ''(see above)''
3mm
7" (5" modifed)

(12) 'TEE' to AIV Control Valve (Top) ''(see above)''
4mm
12"

(13) AIV Control Valve (Bottom) to Intake Front
4mm
13"

(14) AIV Control Valve (Middle) to AIV ''(see above)''
4mm
5"

(15) Throttle to Rear Gallery (driver)
4mm
10.5"

(16) Manifold to 'TEE' ''(see above)''
4mm
35" (25" modified)

(17) Intake to Carbon Canister (right port)
6mm
46" (38" modified)

(18) Headlight Motor Vent Lines (Clear Vinyl Tubing Home Depot)
3/16"
2 x 7"

(19) Vacuum Pump to Vacuum Canister
3mm
~26"

(20) Carbon Canister (middle port) to Fuel Return Hardline
6mm
9"

''VACUUM TANK HOSES''

Intake to Vacuum Tank
3mm
46" (modified)

Cruise to Vacuum Tank
4mm
28" (modified)

A/C Heater Cock Control to Vacuum Tank
3mm
39" (modified)

Vacuum Tank to Firewall
''not measured''
~6 feet

''COOLANT and BRAKE BOOSTER HOSES''

Passenger Side MANIFOLD Coolant Line to Rear Gallery
10mm
9"

Passenger Side COLLECTOR Coolant Line to Manifold
10mm
~5-6" (OEM is formed hose)

Throttle Coolant Line to Driver Side Gallery
10mm
7"

Throttle Coolant Line to Turbo Passage
10mm
10"

Turbo Coolant Line to Driver Side Gallery
10mm
10"

Coolant Reservoir Line to Coolant Tube
6mm
23" (could be shortened)

Manifold to Brake Booster Check Valve
10mm
3" (modified // OEM is formed hose)

Brake Boost Check Valve to Brake Booster
10mm
4" (modified // OEM is formed hose)

egr.jpgaiv_bottom.jpg

NO CHANGE

tb.jpg

intake.jpgnew_intake.jpg

(OLD LEFT || NEW RIGHT)

canister.jpgnew_canister.jpg

(OLD LEFT || NEW RIGHT)

new_vacuum_tank.jpgvacuum_tank.jpg

VACUUM TANK HOSE REROUTE in GREY wire loom (original lines go down, across bottom frame rail, then back up)

Attached Files

pass_carbon.jpg
(62.9 KB)

fpr.jpg
(34.9 KB)

----
'''Z_Karma:''' <small>(2024-04-02 21:43:32)</small>

Link #1 from above post ([http://users2.ev1.net:80/~jboykin/vaclines.htm http://users2.ev1.net:80/~jboykin/vaclines.htm]) aka Z31.com user: Zenarcher, archived from 02/26/2005

'''Charcoal Canister Hoses''' charcan.jpg

The canister is located underneath the vacuum tank near the right headlight. On the front of the canister there are 4 ports. The line in blue is the lower of the 2 closest to the front of the car. That hose runs to the intake pipe after the AFM with a check valve installed inline. The line above that one (green) goes to one of 2 metal tubes in front of the plenum, then on to the throttle body. The line depicted in pink runs to the other metal tube in front of the plenum, then on to a port on the plenum under the brake booster line. The fourth line (yellow) runs straight down to a metal tube and on to the gas tank. There are vacuum 2 ports on the z31 throttle body. I installed a Stanza TB which has only 1 port. I used a Y to connect the 2 lines to go into the one port on my TB. The second hose (green) on the TB connects to the EGR.

***The line depicted in red runs from the plenum to the Boost Sensor located under the coil.***

'''Fuel Pressure Regulator'''

fpr.jpg

Fuel Pressure Regulator lines.

The hose depicted in red coming off the FPR runs into a metal tube passing between the plenum and the distributor cap. Then on to the bottom of the FPR control solenoid.

The line depicted in green comes off the plenum to a metal tube passing between the plenum and the distributor cap, then on to the top of the FPR control solenoid.

'''Climate Control

CCvaclines.jpg'''

Climate Control lines.

There are 4 ports on the reservoir.1. The line depicted in blue goes through a grommet in the firewall to the lines inside the dash.

2. The larger hose depicted in green would go down along the bottom of the engine bay to the Cruise Control actuator.I removed the cruise control from my car.

3. The hose depicted in red comes off a port w/ power. It goes down in the engine bay along the bottom towards the firewall to the heater control valve.

4. The hose depicted in yellow connects to a port on the plenum.

'''Under Dash'''

udash.jpg

'''85T Vacuum Tank'''

vactank2.jpg

Forums/Z31P/Thumper300ZX vac hose diagram site - Revision history

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