Moss Automobile Parts User manual

M:\Product Information\366-348\Instructions\366-348 MGB Fuel Injection Installation Instructions_Grant_2.doc
366-348 Fuel Injection Conversion
Installation Instructions
1975-1980 MGB
with a Zenith Stromberg Carburetor
CARB E.O. Number D-453-4 (75-79)
Introduction
The US Spec MGBs built from 1975 on were designed around the emissions standards adopted by the
United States. The engine and the emission control components constitute a single system that work
together to burn fuel more efficiently and produce less pollution. When new, the cars had a reputation for
cold start problems and general drivability issues. These historical problems have been compounded by a
lack of replacement parts. It’s no surprise that tuning the car and getting it to run correctly is very difficult,
and many owners have found it impossible to meet the emission standards applied to these cars. Instead
of simply getting the ZS carb parts manufactured, we decided to address all of the problems by
eliminating the ZS carb entirely. After considering all the options, we decided to develop a fuel injection
system.
You will be happy to know that the fuel injection system completely eliminates the cold start and general
drivability issues long associated with the ZS carburetor. This kit will turn you MGB into the car you
wanted when you bought it- a classic British sports car that starts every time, runs smoothly, accelerates
cleanly, and is just plain fun to drive. On top of that, this kit (in conjunction with all the original emission
control equipment) brings the car back into compliance with the emission standards. We have gone
through the California Air Resources Board (CARB) certification process and we were issued CARB
Executive Order D-453-4 for the 75-79 MGB as a result.
This kit is designed and engineered specifically for a stock 75-80 MGB in good mechanical condition with
all the original smog equipment in place and working. Before you lift a wrench, do a complete tune-up to
factory specifications. Check the compression, adjust the valves, and most importantly, make sure your
ignition system is working as it should. Worn distributor shaft bushings, old plugs, bad plug wires, worn or
cracked distributor cap and rotor, or non-functional mechanical and vacuum advance mechanisms will not
be cured by adding fuel injection. Our fuel injection system cannot bring a car into compliance with
emission regulations if the catalytic converter is shot.
We realize that many of the 75-80 MGBs no longer have all the original equipment. Many of the ZS carbs
have been converted to a manual choke. Catalytic converters have disappeared. The OE cam may have
been replaced with an earlier version. We have prepared instructions based on two MGBs, a 78 and an
80, that were mostly unmodified and they still had the emissions equipment intact. Cars that have been
modified will require some improvisation, and I regret that we are not going to be able to tell you how to
deal with these variations. We have installed this kit on several cars, and installed and removed it several
times. We have spent literally weeks fine tuning the instructions. Inevitably, there will be something we
missed, or something we did not explain well enough. You can help us improve this product by sharing
your experience- if you have any comment or suggestions, we’d like to hear them. Please log onto
http://www.mossmotors.com/ and select “Contact Us”; a simple email form will pop up.
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M:\Product Information\366-348\Instructions\366-348 MGB Fuel Injection Installation Instructions_Grant_2.doc
Tools Needed
Safety Goggles
Rubber gloves
Electrical tape
Masking tape
Black felt pen/marker (Sharpie)
Pencil
Penetrating oil
Brake Cleaner (aerosol)
Gasket dressing (Hylomar or RTV)
Gasket cement, tacky
Thread sealant, liquid
Permatex #54540 or equivalent
Antifreeze-water mix (50/50)
Wire crimpers
Wire cutters
Single edge razor blades
Hose cutter
Screwdrivers, small medium and large
Flat bladed and Phillips
Open end wrenches: 7/16, ½, ¾, 13/16”
Ratchet 3/8” drive
Sockets: 7/16”, ½”, 13/16”
Extensions, long, medium, short
Torque Wrench. 3/8" drive
Allen wrench 5 mm
Gasket scraper
Locking pliers (vice grips)
Hacksaw
Dremel tool or grinder
Fuel Siphon pump
Fuel storage container
Drill, cordless if possible
3/32” drill bit, #30 (0.1285”) drill bit.
1” hole saw
Jack & Jack stands (4)
Flashlight
Small Mirror
Workshop Manual, Factory or Bentley (215-325)
Nice but not absolutely required
Stud puller
An assortment of nut-drivers will help with the
hose clamps
Before You Begin
You will be working with gasoline. Store fuel in proper containers and avoid any open flames or
other ignition sources. Work in a well ventilated area and observe all normal shop procedures.
As with all projects, please read through all of the instructions before you pick up a tool. We are
not going to thoroughly explain things that are covered in the factory workshop manual. Terms
used: front and rear refers to the front or rear end of the car. Left and right refer to the left and
right side of the car as seen while sitting in the cockpit facing forward.
These instructions include many photographs, mostly of the later cars. Those of you with 75-76
MGBs will recognize this immediately. There will therefore be steps in these instructions that
apply only to the later vehicles, and we have tried to make this clear in the instructions.
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M:\Product Information\366-348\Instructions\366-348 MGB Fuel Injection Installation Instructions_Grant_2.doc
Installation Part 1 – Prepare the Vehicle, Drain Fluids
1. Disconnect the battery ground cable.
2. You will need a solid, level surface to work on.
3. Jack up the rear end of the car and support is securely on two jack stands.
4. Drain the fuel tank. The safest method is to use a fuel siphon pump to transfer the fuel into a proper
gasoline storage container. The original fuel tanks fitted to later cars do not have a drain plug, but if
your tank has one, use it. If you find rust particles or flakes in the tank, consider having the tank
cleaned and sealed. Rust flakes will clog or damage the high pressure fuel pump included with this
kit. If you have any doubts, fit an in-line fuel filter (377-310) in the hose between the tank and the high
pressure pump when you reach that point in the installation.
5. Unpack the fuel injection kit components.
6. Drain the coolant. For the 77-80 sealed system, we need
to break the vacuum. Remove the plug (1.1) screwed
into the top of the thermostat housing using a 13/16”
wrench. Remove the gasket that seals the plug to the
housing. Set the plug aside. A new 328-485 gasket for
the plug is included in the kit which we will use when we
re-fill the system at the very end.
1.1
366-348 Inst Fig 1 [1977-80 MGB]
7. Under the car- Position a pan to catch the coolant.
Loosen the clamp on the lower radiator hose and pull the
hose off the radiator outlet. When the coolant has
drained, replace the hose and tighten the clamp. The
original radiators fitted to later cars did not have drain
taps, but if your have one, use it Collect the coolant in a
clean container and set it aside- you will re-fill the
system with this coolant at the end.
366-348 Inst Fig 2D
2.12.1
Part 2 - Remove the ZS Carb
Wear eye protection. As you disconnect cables & hoses from
the carb, take the time to label them- use the black felt pen
and masking tape. It will avoid confusion later.
8. Disconnect the throttle return spring.
9. Trace the fuel hose from the filter on the firewall to the
carb. Loosen the hose clamp on the hose at the carb
and pull the line free carefully. Wrap a rag around the
end to catch any fuel that comes out. Even though the
tank is drained, there will be fuel in the carb and in the
fuel hoses. If you have late MGB, you may find a
mechanical fuel cutoff valve between the filter and the
carb. Disconnect and remove the hoses; the valve will
be removed later. See Part 7 for more information.
10. Remove the air cleaner assembly (2.1).
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366-348_Inst_Fig 3
366-348_Inst_Fig 2C
2.2
2.2
2.4
2.3
3.1
2.6
2.7
11. Locate the water choke on the ZS Carb (2.2).
12. Loosen the hose clamp and disconnect the coolant hose
that runs from the water choke (2.3) to the water choke
outlet at the back of the cylinder head.
13. Loosen the hose clamp and disconnect the coolant hose
that runs from the water choke (2.4) to the steel coolant
line (2.6) that runs next to the exhaust manifold.
14. Loosen the hose clamp and disconnect the coolant hose
at the nipple on the coolant hard line (2.7) If the hose is
difficult to remove, slice it lengthwise with a razor blade
at the nipple (3.1). If the ZS carb has been converted to
a manual choke, you may find that the hose will run from
this nipple (3.1) to the fitting at the back of the cylinder
head (see 4.2 below). In other cases, the nipple (3.1)
may have been capped off or plugged with a piece of
hose and a bolt. If your MGB has been fitted with a
manual choke, you may remove the cable assembly
from the car.
15. Locate the hose (4.1) attached to the water choke outlet
(4.3) which is attached to the back of the cylinder head.
16. Loosen the hose clamp (4.2) and disconnect the hose.
If the hose is difficult to remove, slice it lengthwise with
a razor blade at the nipple. If you must cut the hose off,
try not to score the metal tube too deeply, or you may
create a water leak that will be hard to fix later
366-348_Instructions_Fig 4
4.1
4.2
4.3
366-348_Instructions_Fig 5B
5.1
5.2
366-348_Instructions_Fig 5C
5.3
17. Locate the hose (5.1) that runs from the carbon
canister to the carb. You may find that the ends are
rubber hose with a steel line in the middle (5.2).
Disconnect it from the carb. Disconnect the hose at
the canister (5.1) and cap the hose nipple on the
canister with the ¼” cap (5.3) provided in the kit. The
cap in the kit will not require the hose clamp you see
here…
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M:\Product Information\366-348\Instructions\366-348 MGB Fuel Injection Installation Instructions_Grant_2.doc
366-348_Instructions_Fig 6
6.1
366-348_Instructions_Fig 6B
6.2
6.3
18. Locate the hose (6.1, 6.2) that runs from the
carb to the crankcase vent pipe (6.3) on the
front of the engine.
19. Loosen the hose clamp at the carb and
disconnect the hose.
20. Loosen the hose clamp at the crankcase
vent pipe (6.3) and remove the hose. This
hose will be replaced by a new hose
supplied in the kit.
366-348 Inst Fig 7
7.2
7.1
366-348 Inst Fig 8
8.2
8.1
21. Locate the EGR valve actuator (7.1). Check
the base of the EGR valve for any signs of a
leak. A leak here will affect how the car runs
and will make tuning the car difficult. If there
is any doubt, remove the valve and inspect
the gasket. If there are signs of a leak, you
must replace the 293-420 gasket. This gasket
is not supplied in this kit.
22. Disconnect the small hose (7.2) running from
the carb to the actuator at the actuator.
23. Find the 5/32” vacuum cap (8.1) provided in
the kit and cap the hose nipple on the
actuator. Push the vacuum cap down over
the nipple far enough to go over the flared
section (8.2) of the nipple.
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M:\Product Information\366-348\Instructions\366-348 MGB Fuel Injection Installation Instructions_Grant_2.doc
366-348 Inst Fig 9
9.2
9.1
24. On the back of the carb, locate the throttle cable (9.1)
and the bellcrank (9.2)
25. Disconnect the throttle cable (9.1) and let it hang loose
as shown in Fig 9. The throttle cable is secured to a
bracket on the heat shield and that will be removed
shortly.
26. Remove the four nuts that secure the carb to the intake
manifold. This is tedious because you will have to use an
open end wrench and there is little room to move it.
366-348 Inst Fig 10
366-348 Inst Fig 11
11.2
11.1
27. Once the four nuts are removed, grasp the carb and pull
it away from the manifold. If a sealer was used on the
gasket the last time the carb was installed, you may
have some trouble pulling the carb off the studs.
28. Once the carb is loose, hold it upright because the float
bowl is full of fuel.
29. Carefully empty the fuel into an approved container and
set the carb aside. Your old ZS carb should not be
discarded; they are getting rarer all the time. Keep it or
sell it to someone who’s looking for one.
30. Locate the carb spacer / heating element. (11.2)
31. Remove the green wire (11.1) and wrap the end with
electrical tape; it will not be used anymore.
32. Plug the hole in the manifold with a shop rag to keep
debris out of the engine.
33. Disconnect the throttle cable from the heat shield.
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11.6
11.5
11.3
11.4
34. Locate the nut (11.3) securing the heat shield bracket
(11.4) to the stud (11.5) on the heater return pipe.
Remove the nut and save it-we will need it later.
35. Remove the heat shield bracket (11.4) and the heat
shield (11.6) by pulling it up and off the 4 carburetor
studs and the stud (11.5) on the water pipe. Set it aside.
36. Remove the four studs that secured the carb to the
manifold. Spray the studs with penetrating oil and let
them soak. Double-nut the studs and unscrew them. If
you have a stud puller, use it. Since these studs will be
discarded, you may use vice grips if necessary. If the
studs won’t budge at first, let the penetrating oil have a
chance to soak in for 30 minutes and give it another try.
366-348 Inst Fig 12
12.1
12.2
37. Once the studs are out, scrape the surface (12.1) clean
using a gasket scraper and/or single edge razor blades.
Spraying some brake cleaner on the gasket residue will
soften it, making it easier to scrape off. Although
missing in the picture, keep a rag stuffed into the hole in
the manifold (12.2) to keep debris out. Be careful not to
gouge the surface.
If you took your safety goggles off, put them back on before
to do this step! We must clean out the threaded holes in the
manifold because we will be using Loctite on the bolts that
secure the throttle body, and the penetrating oil residue will
prevent the Loctite from bonding with the metal.
366-348 Inst Fig 13
13.1 13.2
38. Spray brake cleaner into the holes while holding a rag
over the hole and the nozzle of the can to catch the
splash back.
39. Remove the heat riser. The heat riser (13.1) is secured
using one on the manifold nuts (13.2). Remove the
manifold nut using a ½” socket, extension and a ratchet.
40. Remove the heat riser and replace the manifold nut. Use
the torque wrench and tighten the nut to 15 ft-lbs.
This concludes Part 2 of the installation.
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Installation Part 3-Modification of the Heat Shield
The heat shield will be modified and reinstalled with the fuel
injection throttle body. Although it is possible run a car with
the fuel injection system installed without the heat shield, the
under-hood temperature will be quite high, and we strongly
recommend against it.
366-348 Inst Fig 14
14.1
14.2
14.3
14.1
41. Remove the two Phillips head screws (14.1) that secure
heat shield bracket (14.2) to the heat shield (14.3). The
screws will be re-used to re-attach the heat shield in a
few minutes. If your heat shield is in bad shape, it can be
replaced with a new one (14.3, Moss # 373-945) as we
have done here.
42. Examine the heat shield bracket (14.2).
43. Locate the lip on the right side (15.1) and the lip on the
left side (16.1) of the intake opening. This lip or flange
must be partly removed from both sides in order for the
throttle body to sit flat.
366-348 Inst Fig 16
16.116.1
16.2
366-348 Inst Fig 15
15.115.1
15.2
15.3
16.3
44. Measure down 3.5” from the top of the bracket and mark
the bracket (15.2, 16.2) to indicate how much of the lip
will be removed.
45. Scribe a line along the 90 degree bend where the lip is
formed (15.3, 16.3). Although we used a white marker so
it would show up in the picture, a pencil will work fine.
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17.1
366-348 Inst Fig 17
17.2
46. Cut the bracket to remove the 3.5” long section of
the lip or flange from both sides (17.1, 17.2). You
can make the cuts with a hacksaw. You can also
use a grinder, jig saw, or a Sawzall instead of a
hacksaw.
47. Lightly file the edges where both cuts were made to
remove any burrs. At this point you may want to
repaint the bracket. Strip the rest of the paint, get rid
of the rust, and then spray it with a good high temp
automotive primer. Finish coat should be black.
48. Reattach the modified bracket to the heat shield
using the two original Phillips head screws.
This concludes Part 3 of the installation.
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366-348 Inst Fig 18C
18.1
366-348 Inst Fig 18
366-348 Inst Fig 18D
18.3
18.2
Installation Part 4 - Fitting the Throttle Body
49. Pick up the throttle body. Note that one of the four
mounting bolts has already been installed, and the
throttle stop was installed afterward. This effectively
traps the bolt. NOTE: The throttle stop has been preset
and the Electronic Control Unit (ECU) has been
calibrated using this throttle stop. UNDER NO
CIRCUMSTANCE SHOULD YOU DISTURB OR
ATTEMPT TO ADJUST THE THROTTLE STOP!
50. We will test-fit the end of the throttle cable first. Look at
the black plastic bell crank (18.1) on the throttle body
and note that a hole has been drilled to accept the pin on
the end of the throttle cable. Note also that a slot has
been cut to allow the throttle cable to be pushed into the
groove in the bell crank.
51. Hold the throttle body (18.2) in your left hand and use
your thumb to push the pin on the end of the cable (18.3)
into the hole in the bell crank. Some cleanup of the hole
or slot may be necessary to get a smooth fit.
52. Work the cable through the groove so that the cable can
wrap around the bellcrank.
53. Once the fit is satisfactory, remove the throttle cable
(leaving it in the car) and return to the bench with the
throttle body.
54. Find the other three 5/16-18 X 1” bolts included in the kit.
Fit a second bolt to the throttle body so that both of the
lower holes have a bolt (19.1).
366-348 Inst Fig 19
19.119.1
19.3
19.2
55. Find the two square manifold gaskets for the throttle
body (19.2).
56. Put a dab of tacky gasket cement (not provided) on the
throttle body and place a square manifold gasket over
the two lower bolts (19.1) with the tab (19.3) on the
gasket “up”. The tacky gasket cement is used to hold the
gasket in place, not to help the seal.
57. Put a dab of tacky gasket cement on the modified heat
shield assembly and place a second square manifold
gasket over the four bolt holes in the heat shield. The
tacky gasket cement is used to hold the gasket in place,
not to help the seal.
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58. Hang the modified heat shield assembly in position, (with
the gasket toward the manifold) using the stud on the
water pipe to support the heat shield. The four bolt holes
in the heat shield should line up with the four holes in the
manifold. Replace the nut on the stud on the water pipe
loosely- we just want to keep the heat shield assembly in
position.
366-348 Inst Fig 20
20.1
59. Apply a drop or two of blue Loctite to the threads of the
two lower bolts. The Loctite in the kit is in s small plastic
tube. Cut of a corner to make a very small opening and
squeeze a little Loctite on the threads. You only need a
drop of two.
60. Hold the throttle body with the throttle bell crank toward
the rear of the car. Carefully position the throttle body in
the engine compartment. You will have to hold the two
lower bolts in place as you maneuver the assembly into
position. (Fig 20)
61. Hold the throttle body up against the heat shield and
thread the two lower bolts through the heat shield and
into the threaded holes in the manifold, starting with the
lower front bolt (the one on your left as you look at the
throttle body).
62. Apply a drop or two of blue Loctite to the threads of the
two upper bolts (5/16-18 X 1”). Thread them into place
starting with the upper left bolt (20.1).
63. Once all four bolts are started, tighten them using a ½”
open end wrench. They should be torqued to 18 ft-lbs.
There is no way to get a torque wrench in there,
although you might get a crows-foot on a bolt. If you are
not comfortable judging 18 ft-lbs, tighten a bolt you can
get to 18 ft-lbs, then put a wrench on it to see what 18 ft-
lbs feels like. This completes part 4 of the installation.
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Installation Part 5 - Laying the Harness in Place
366-348 Inst Fig 21
21.1
366-348 Inst Fig 22
22.2
22.1
The brain of the fuel injection system is the Electronic
Control Unit, or ECU. This will live in the cockpit. The wiring
for the kit consists of a single harness that starts in the
cockpit and it has one branch with several molded plastic
connectors that goes to the throttle body and one branch
with no connectors that goes toward the coil and fuse box. A
single red-white wire will go the new fuel pump we will install
by the rear axle.
64. Remove the right hand (passenger’s) under-dash panel
if fitted; many have been removed or lost. If you look up
at the back side of the firewall, you will see a rectangular
rubber grommet (21.1). We are going to modify it so we
can get the fuel injection harness into the cockpit.
65. Pop out the rectangular grommet (21.1) from the hole in
the right side of the firewall.
66. Cut a 1” hole in the plug using a hole saw (22.1). Avoid
the middle rib. Slice the grommet from the hole to the
bottom edge of the grommet using a single edge razor
blade. (22.2) If you don’t have a hole saw you can cut
the hole with an Exacto knife, razor blade or punch.
67. Find the end of the wiring harness (23.1) with the two
large rectangular white plastic connectors or plugs
(23.2).
68. From the engine compartment, poke about 1 foot of the
harness through the hole in the dash.
366-348 Inst Fig 24
366-348 Inst Fig 23
23.2
23.1
23.2
24.1
69. Leave the harness hanging in the footwell for now
(24.1). We just want to make sure we have enough
slack to reach the ECU when we install it later.
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366-348 Inst Fig 25
25.1
25.225.2
70. Locate the branch of the harness that has the relay
(25.1) and the inline fuse holders (25.2), and route it
over to the right hand side of the engine compartment.
Although missing in this particular picture, we encourage
the use of fender covers or towels to protect the paint.
71. Locate the branch of the harness with the molded plastic
connectors and carefully route it over toward the throttle
body. Take your time, and run the harness under the
heater hoses, behind vacuum lines and the stock wiring
harness bundle.
72. There will be a bundle of red-white wire hanging down
near the back of the engine. (see Fig 25C) This will
provide power for the new fuel pump and we will deal
with it when we run the fuel return hose.
366-348 Inst Fig 25C
This completes part 5 of the installation.
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Installation Part 6 - Connecting the Harness to the Throttle Body
73. Locate the connector on the harness for the
Idle Air Control Motor and plug it in. (26.1)
366-348 Inst Fig 26D
366-348 Inst Fig 26
26.126.1
26.2
26.2
18.126.3
366-348 Inst Fig 26B
366-348 Inst Fig 26C
74. Locate the connector on the harness for the
Fuel Injector and plug it in. (26.2)
75. Locate the connector on the harness for the
Throttle Position Sensor (TPS) and plug it in.
(26.3)
76. Each connector has clips that lock the
connector in place; make sure these are
engaged after you plug in the connector.
All three connectors are unique and there is no
way to make a mistake plugging them in.
This completes part 6 of the installation.
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Installation Part 7 – Installing the Manifold Absolute Pressure (MAP) Sensor
The MAP sensor is a variable resistor used to monitor the
difference between the pressure inside the intake manifold
and normal atmospheric pressure outside the manifold.
This information is used by the electronic Control Unit
(ECU) to determine engine load. When the engine is under
load, the computer will alter the fuel mixture to improve
performance and reduce emissions. Before we get started
we need to make a place for the MAP sensor. Some late
MGBs came equipped with a mechanical fuel cut-off valve
that sits on the firewall shelf near the pedal box and fuel
filter. The valve (27.1, 27.2) is connected to the fuel hose
between the fuel filter and the carb. These valves are
prone to failure, and most of them have already been
removed. If you have one, we suggest thay you remove it
366-348 Inst Fi
g
27B
27.2
366-348 Inst Fi
g
27A
27.1
along with the 2 pieces of hose attached to the valve.
77. Locate separate bag that contians the Manifold
Absolute Pressure (MAP) sensor. It is a small black
plastic box (27.3) with a nipple for a vacuum hose
(27.4) and a socket for a wiring connector (27.5).
366-348 Inst Fi
g
27C
27.3
27.5
27.4
27.7
27.6
78. Connect the harness plug (27.6) and position the MAP
sensor so there is slack in the wires. It fits nicely on
the firewall shelf near where the throttle cable guide is
mounted (27.7).
79. There are two slots for screws at either end of the
plastic box; the screws can be positioned anywhere in
those slots. Mark the position of one of the screws.
80. Remove the MAP sensor and look under the dash in
the cockpit- make sure there are no wires in the area-
you are about to drill a couple of holes.
81. Center punch your mark and drill one hole using a
3/32” drill bit.
366-348 Inst Fi
g
28
28.1 28.3
28.2
82. Find the two #6 x 1 ¼” sheet metal screws and the two
#6 flat washers provided in the kit. Secure the MAP
sensor to the firewall shelf using one screw and
washer (28.1).
83. Using the MAP sensor as a guide, drill a second hole
using a 3/32” drill bit and install the second screw and
flat washer. (28.1) Do not over-tighten. The flat
washers were not used in the installation
photographed- that’s when we decided they were
needed.
84. Pull the rubber bellows/cover (see 27.2 on previous
page) off the vacuum nipple, exposing the plastic hose
barb (28.3).
This completes part 7 of the installation.
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Installation Part 8 - Engine Coolant Temperature (ECT) Sensor
366-348 Inst Fig 30
30.1
366-348 Inst Fig 31 366-348 Inst Fig 32
31.1
31.132.1
85. Locate the factory water choke outlet at the left rear
corner of the cylinder head. When cars are converted to
a manual choke, this outlet is sometimes removed. If
yours is missing, you will need a Moss #470-245 water
choke outlet because engine coolant must flow past the
ECT in order for it to work properly.
86. Remove the clamp (30.1) securing the choke coolant
hose to the water choke outlet. Pull the hose off the
tube. You may want to take a moment and clean the
area around the choke tube before you start the next
step.
87. Remove the two nuts (31.1) securing the water choke
outlet to head using a 7/16" combination wrench.
Remove and set the water choke outlet aside with the
nuts. They will be re- installed after we fit the engine
coolant temperature sensor (ECT).
366-348 Inst Fig 33 366-348 Inst Fig 34
366-348 Inst Fig 35
366-348 Inst Fig 36
88. Remove the two studs (32.1) from the head. It will be
necessary to double nut the studs or use a pair of vice
grips to break them loose. (Fig 33, 34) Discard them;
they will be replaced with longer studs supplied in the kit.
If the studs are very hard to move, try soaking them in
penetrating oil for 30 minutes before you try and remove
them.
89. Clean the surface of the head thoroughly, removing any
gasket material or sealant. Use a gasket scraper or a
single edged razor blade. (Fig 35) Take care not to
gouge the surface, which may cause a leak later. It may
be easier to remove the gasket and gasket residue if you
spray it with brake cleaner and let it sit for awhile.
90. When you are done, the surface should be clean and
free of any debris that might prevent a good seal. (Fig
36)
If you took your safety goggles off, put them back on before
to do this step!
91. Spray brake cleaner into the holes for the studs while
holding a rag over the hole and the nozzle of the can to
catch the splash back.
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M:\Product Information\366-348\Instructions\366-348 MGB Fuel Injection Installation Instructions_Grant_2.doc
366-348 Inst Fig 37 366-348 Inst Fig 38
92. Locate the two 1/4-28 x 2” studs supplied in the kit.
93. Apply thread sealant (Permatex 54540 or equivalent) to
the last ¼ inch of each stud. (Fig 37)
94. Thread the ends of the studs with sealant into the holes
at the back of the head. (Fig 38)
95. Locate the two water choke outlet gaskets (Moss p/n
295-040) supplied in the kit. You may want to use a very
thin layer of Hylomar or RTV on the gaskets when you
install them
366-348 Inst Fig 39
366-348 Inst Fig 39B
96. Slide one gasket over the studs. (Fig 39)
97. Test fit the aluminum adaptor, the second gasket, and
the water choke outlet. Make sure the studs extend
above the head far enough to accept the lock washers
and nuts. If not, unscrew them a turn or two. (Fig 39B)
98. Find the engine coolant temperature (ECT) sensor (Fig
40) supplied in the kit and the aluminum adaptor block it
threads into (Fig 41). There should already be Teflon
tape around the threads of the ECT (40.1). If you ever
replace this sensor, wrap Teflon tape around the threads
before installation.
99. Thread the ECT sensor into the ECT adapter block. (Fig
42) Just get it started. We will tighten it after it is installed
on the head.
100. Slide the ECT adapter block over the two studs and
down on top of the first choke tube gasket (Moss p/n
295-040). (Fig 43)
101. Slide the second water choke outlet gasket (Moss
p/n 295-040) on top of the ECT adapter block. Place the
water choke outlet on top of the gasket. (Fig 45)
102. Install the ¼” lock washers (Moss 772-269) provided
in the kit on the studs. Install the 1/4-28 nuts that you
removed earlier onto each stud and torque them to 9 ft-
lbs. (Fig 45).
103. Use a 3/4” combination wrench to tighten the sensor
into the sensor block. (Fig 46) It must be snug or you will
find coolant weeping past the threads.
366-348 Inst Fig 41
40.1
366-348 Inst Fig 40
366-348 Inst Fig 42 366-348 Inst Fig 43
366-348 Inst Fig 45
366-348 Inst Fig 46
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M:\Product Information\366-348\Instructions\366-348 MGB Fuel Injection Installation Instructions_Grant_2.doc
104. Find the fuel injection harness connector with the
blue inner seal (47.1) Connect it to the to the ECT
sensor. The clip on the connector (47.2) should snap
into place.
366-348 Inst Fig 47
47.1
47.2
366-348 Inst Fig 48
105. Locate the 22” long piece of 3/8” heater hose
supplied in the kit (Moss #051-260). Slide a small hose
clamp (supplied in kit) over the end of the hose and push
the hose onto the water choke outlet and tighten the
hose clamp.
106. Route the 3/8” hose (49.1) from the water choke
outlet over the top of the throttle body (49.2) and down
towards the nipple in the coolant hard line. (49.3).
Remove the cap or plug on the nipple if present.
366-348 Inst Fig 49
366-348 Inst Fig 50
49.3
49.2
366-348 Inst Fig 51
51.1
49.1
107. Slide a small hose clamp (supplied in kit) over the
end of the 3/8” hose (51.1) and push the hose onto the
nipple. Tighten the hose clamp.
This completes part 8 of the installation.
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M:\Product Information\366-348\Instructions\366-348 MGB Fuel Injection Installation Instructions_Grant_2.doc
Installation Part 9- Tapping into the Tachometer Wire
108. If you have a “Federal” MGB (built for sale outside
California) you should have a cylindrical barrel-type coil
(60.1). Locate the two white w/black stripe wires
attached to the negative side of the coil (60.2). Look at
the coil; the negative side of the coil should be marked
with a “-“. One white w/black stripe wire goes to the
distributor and the other goes to the tachometer. Both
disappear into the wiring harness so it is hard to tell
which is which.
366-348 Inst Fig 60, Federal MGB
60.1
60.2
109. If you have a “California” MGB you may still have
the electronic ignition coil fitted that was part of the
emissions control equipment (61.1). Find the two white
w/black stripe wires (61.2) attached to the coil.
61.1
110. In either case, once you have located the two white
w/black stripe wires, try to determine which of the wires
runs to the tachometer. This may prove a challenge.
Although we can tap into either wire, it is best to use the
tachometer wire.
61.2
366-348 Inst Fig 61 1979 California MGB
111. Find the T-Taps supplied in the kit (Fig 62). One
the cars with a regular coil, you could put a #8 ring
connector on the white wire and secure it to the negative
terminal on the coil. On the cars with the electronic
ignition coil, the wires disappear into the coil and you
cannot do that- which is why we supply a t-tap in the kit.
366-348 Inst
Fig 62
63.1
366-348 Inst Fig 63
112. Place a T-tap on the white wire with a black stripe
(white-black) that goes to the tachometer. (63.1) (Again,
either wire will work).
This connection will provide a tachometer/RPM signal to the ECU while allowing the tachometer
and distributor to continue to work normally. Note: If the wires are old, squeezing the T-tap may
force the blade into the insulation without actually penetrating to the wire strands inside the
insulation. After installing the T-tap, use an OHM meter to verify continuity between the female
spade in the T-tap and white-black wire. On the Federal cars, check continuity to the negative
terminal on the coil. On the California cars there is no visible negative terminal because the white-
black wire disappears inside the coil. You will need to penetrate the wire with a sharp probe.
This completes part 9 of the installation.
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M:\Product Information\366-348\Instructions\366-348 MGB Fuel Injection Installation Instructions_Grant_2.doc
Installation Part 10- Terminating & Connecting the Fuel Injection Harness
366-348 Inst Fig 65
65.4
61.365.3
65.1
65.2
65.5
65.7
65.6
113. Organize the various electrical connectors supplied
in the kit.
114. Find the two black wires that have inline fuses (65.1,
65.2). These are the fuel injection harness power leads.
115. Strip the ends and crimp one female spade
connector (65.3) onto each of these two wires. Be sure
to crimp these connections securely, as they are
necessary for the car to run. Use proper wire crimpers. A
poor connection on one of these wires will cause lots of
trouble.
116. Find the black wire w/white stripe (65.4). Strip the
insulation off the end and crimp a ring connector with a
¼” hole (supplied in kit) onto the wire. (65.5)
117. Find the solid white wire (65.6). Strip the insulation
off the end and crimp a male spade connector onto the
wire (65.7).
366-348 Inst Fig 66 1979 California MGB
66.1
66.2
118. Connect the male spade connector (66.1) on the
fuel injection harness’ white wire to the t-tap (66.2) that
is crimped onto one of the white w/black tracer wires
leading to the negative side of the ignition coil. The
white wire feeds the ECU the same signal the
tachometer sees; the white wire tells the ECU the engine
RPM. This signal is critical. Check the continuity
between the negative terminal on the coil and the white
wire. Use a probe to penetrate the insulation if
necessary.
366-348 Inst Fig 67 1979 California MGB
67.1
67.2
119. Find the black wire with white stripe with the ring
connector with a ¼” hole on the end. (See 65.5 above)
120. Using a 7/16” socket, remove one of the bolts (67.1)
securing the ignition coil bracket. (80 MGB Shown)
121. Slide the ring connector (67.2) onto the coil bracket
retaining bolt under the washer and retighten the bolt.
Putting the ring connector under the washer will prevent
the connector and wire from being spun around as you
tighten the bolt.
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