I am back again needing help on my 1980 MGB that will run but will not
start. (Can pull to start). Starter turns over fine and fast.
I ask for some help back in March (slow to work out problems and covered
with other priorities). I feel like I have a bad connection some where.
While checking connections and occasionally trying to start engine, it
started once but not since. Again my working on it has not been consistent.
I had one suggestion to check the voltage at the positive connection on the
coil; Should be high (10-12V) both just with the key on and while cranking.
If the voltage was low (or none) while cranking I should have a bad
connection from the starter solenoid. This could be verified by using a
jumper wire from the fuse box to the positive terminal on the coil, which
should cause it to start.
My voltage at the positive on the coil is high both while cranking and just
with the key on. However, using a jumper wire to the fuse box causes it to
start. Removing the wire it continues to run just fine.
I am still trying to clean up and chase all the connections, as I feel it is
a poor connection somewhere.
However, while I am working on the problem I am still open to any and all
suggestions. I also have some questions:
What is the best way to clean the female part of the type connecters that
slip over a spade terminal (such as on the starter solenoid relay)?
Also, How can you bend / tighten the tang to tighten the connection?
My distributor has a vacuum advance but has never had a vacuum hose to it.
Normally runs just fine and accelerates good. See below for my coil and
electronic ignition set up. Should I change this?
My wiring doesn’t match any of the diagrams I can fine. I have John Twist’s
book, Haynes, The Complete Official MGB (Bentley), Porters, Chilton and
Clymer.
Coming from the Distributor, I have 3 “small wires” to a plug. Black,
White and Grey.
Coming out of the plug: There are 3 “normal size” wires. Black, White and
Grey.
These go into the Electronic Ignition Module. Gold colored - Crane Cams -
XR700 Ignition - CARB D-47-2&3 Daytona Beach, Florida. I have no
papers for this.
Coming out of the module is a “large” black wire to the screw mounting the
module to the fender. Has a label: Ground see Instructions for Positive
Ground.
Also coming out of the module is a “large” Yellow wire to the negative post
on the coil. Has a label: - Coil Bosch 1.
Also coming out of the module is a “large” Red wire to the positive post on
the coil. Has a label (very faded but I think says): + Coil Bosch 15.
Coil is an Intermotor 11050.
Coming off the negative terminal on the coil (in addition to Yellow above)
is a Brown wire that is not connected to anything.
Also coming off the negative terminal on the coil is a White wire with Black
strip that goes into the harness and I think goes to tachometer.
Coming off the positive terminal of the coil is a White wire (no stripe)
that goes into harness. I have not been able to determine where this goes.
????
Mounted on the fender below the fuse box is what I think is a resistor
(Mounted by being stuck in a clip on fender). It has plastic base on top
site with two posts. Sides are metal. Size is approximately 1 1/8” tall x
¾” wide x ¾” thick. The bottom terminal has a “big” Green wire going into
harness and the top terminal has a “big” White wire with Brown strip going
into harness. What is this and is it needed in my set up.
The harness looks original and unmodified.
The colors of wires on what I think is the starter solenoid relay (mounted
on the left fender even with the fuse box and between the fuse box and the
fire wall) match the wiring diagrams and seem to be wired to match
diagrams.
On the starter solenoid I have:
The “big” black cable from the battery.
3 “large” Brown wires that go into a harness and up (have not completely
traced yet). These are on same post with the battery cable.
On a spade connector I have a White wire with Brown strip that goes to
harness and I think to the starter solenoid relay. There is a small spade
terminal on the solenoid with nothing attached.
I don’t think I have the connection from the solenoid to the positive
terminal on the coil, which is shown on the diagrams as a White wire with
Light Green stripe.
I apologize for the many questions and length, but any and all input is
appreciated.
Phil Farmer
http://www.seark.net/~swimmer - Arkansas Swimming Home Page
Monticello Marlins (Arkansas Swimming - USS)
Monticello Billies High School Swim Team
Burlington Ind.
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