Questions & Answers
Page 1 (MG)
Name: Rick
Subject: Midget, no clutch peddle
Question: Hello howard,
I have a 1969 Midget 1275cc. It has been sitting for over a year. The
engine starts fine. I bled the brakes and clutch but the clutch peddle is soft
and does not engage. I topped off fluid (DOT 4), bled line yet no peddle.
I did same, waited overnight, tested peddle (nothing) repeated process but to no
avail. There is no leak of fluid in the system. I rebuilt the slave
four years ago and the car ran fine then. The car has less than 50 miles on it
since then.
Answer: Hi Rick,
Try one more type of bleed. Remove about half of the fluid in the master
cylinder and Go down to the slave cylinder and with a pry bar, force the arm and
rod back into the slave cylinder all the way very hard and fast. This forces
much of the fluid back into the reservoir. (and any air in the system) Now, pump
the pedal very slowly down and very-very slowly up. The reason you must let the
pedal up slowly is because sometimes it is much easier for air it go in around
the main seal then it is for new fluid to go down from the reservoir into the
mastercylinder.
If this don't work you either need to rebuild the master cylinder or purchase a
new one.
Let me know,
Howard
Name: David
Subject: 72 MGB overheating and clanking
Question: QUESTION: My son and I are working on restoring a 72 mgb. It
will run smoothly and then start clanking - very iradically. At the same time
the temp will approach the hot zone -- even with the thermostat removed.
Does it need a new water pump???
Thanks, dave
ANSWER: Hi David,
What you describe narrows the problem down to 1000 things so you need to do some
testing. First thing you should not run the engine without a thermostat in it.
That will not make it run cooler and can make it run even hotter.
A "clanking" noise is useless information unless you can raise the
hood and listen to where the noise is coming from.
To check a water pump look under the front center of the pump to see if it is
dripping any coolant then loosen the belt and feel the pulley for any up/down
play and rotate the pulley to see if it feels smooth. The only other thing that
can go wrong with a water pump is the impeller come loose inside and the only
way you can check that is to check coolant flow and that can be checked roughly
by removing the thermostat cover and thermostat and disable the ignition
and spin the starter to see if you have good coolant flow out of the housing.
This should be done with the engine hot as a loose impeller may be ok and tight
on the shaft when cold. This is very unusual on MG so it would be a least likely
fault.
Look at the tail pipe when you rev the engine to see if you see any white smoke
which would indicate a blown head gasket. Also with the engine cold, remove the
white wire with a black tracer from the coil and open the coolant
expansion tank and with a flash light look at the coolant level while someone
spins the starter. If you see bubbles or the coolant level raise, that is an
indication of a blown head gasket also.
Let me know,
Howard
---------- FOLLOW-UP ----------
QUESTION: Howard,
It looked like water is flowing from the upper hose (back to the radiator = so
the water pump appears to be working. Also we have not seen any leakage. The oil
looks ok, not milkly and the exhaust looks ok (no white smoke). The plugs look
sooty - but it is run rich with the choke out.. I did a compression test 150,
145, 143,143 -- the 72 does not have an expansion tank. -- the
"clanking" seems to be coming from the bell housing and is very random
--- it even happened when the engine was cold..
Name: Todd
Subject: 79 Midget - Courtesy Light Door Switch
Question: I bought a door switch for that turns on the courtesy light when the
door opens. I went to install it, but when I pulled out the old one, there were
three wires coming into it, whereas my new switch only has a place for one wire
to soldered. Any recommendations? Could it be that only one wire will work?
Thanks for any advice.
Answer: Hi Todd,
There is only one connection and one wire for the light and that is purple with
a white tracer. The switch grounds that wire to make the light work. The only
other wires I ever seen in that area were for door speakers if it has them.
Howard
Name: Rodney
Subject: Simple Question about battery
Question: Hi - I've just got a 1968 MG midget. it runs ok (some of the time!)
but i took the battery out a while back and can't remember which is the +ve and
-ve cable. One cable runs into the dash, the other runs to the dynamo (i think).
Which way around whould i connect the battery? Looking forward to your response.
Thanks.
Answer: Hi Rodney,
The 68 MG Midget came with negative ground even though it had a DC generator, so
the positive battery cable was connected to one side of the starter solenoid and
the negative cable was connected to the body. (ground)
None of the Midgets ever ran the battery cable to the generator nor to the dash.
Howard
Name: Robert
Subject: 1977 MGB Front Brake Problem
Question: My 1977 MGB roadster has a right front brake caliper that binds badly.
This began when I replaced the brake master cylinder, hoses, and calipers. The
right front caliper has been replaced twice with new due to a leak in the
original replacement caliper. The brake lines are in good condition and are
clear of any obstructions. I've swapped the brake hose with the left one and the
problem continues. On the recommendation of another, the right wheel bearings
have been replaced with new and properly shimmed. The binding doesn't happen
immediately upon test driving the car. It only occurs after having driven the
car for a time.
Answer: Hi Robert,
You need to separate weather the binding is mechanical or hydraulic. This is
easy to determine. Just jack up the front of the car when it is dragging and try
to rotate both wheels. Then open the bleeder valve on binding caliper. If the
wheel frees up and it spins ok then. It is something in the line to that wheel
if the other front wheel spins free all the time.(check from the joint in the
steel line to the connection on the caliper) If the wheel is still in a
bind when the valve is opened then you need to look at the brake pads or the
seals on the pistons in the caliper. Don't forget to check for wheel rotation
with the pads out to be sure the wheel bearings are not the cause.
Howard
Name: Bob
Subject: fuses
Question: I noticed that on one side of my 75 Midget the back tail light was out
and the other side's parking light was out. The other lights all worked.
When I checked the fuse the bottom fuse was burned out. I took the second
to the bottom fuse and put it in it's place and the lights came on. I put
the good fuse back where it came from, bought a box of 35 amp fuses and placed
it in the empty slot where the old burned out fuse was. Immediately it
started to smell, so I pulled it out. Why when I put the old 35 amp fuse
that was working in the slot earlier, it worked fine, but when I bought new 35
amp fuses and placed it in the slot (now all fuses should be working) I seemed
to be burning? Not sure what I should do.
Answer: Hi Bob,
First you can not burn a 14 ga wire with a 35 amp fuse and if you used domestic
fuses you can't smell a fuse burning. You might smell a Lucas fuse burn as the
caps are not sealed well on the glass tube. However if you smell the fuse it has
already burned.
When working on electrical problems on cars I made up a test lead with a
resettable circuit breaker (35 amp) and with alligator clips on the end of the
test leads. Other wise you will need a large box of fuses.
If you keep burning fuses, you need a wiring diagram of that car and trace all
items on that fuse.
Are you talking about the "Side marker" lights when you say parking
light, because the parking light and the tail light are just two names for the
same light.
The right hand tail light, side marker and license light are on that second
fuse. If you put a 35 amp fuse in and it burns away you need to look at each of
the 5 lights on that fuse. Unplug the right side marker and parking light on the
front and back at the lights (red wire) including the license light. Put in a
new 35 amp fuse (second position) then reconnect each red wire (parking lights
turned on)and note that the light comes on and the fuse don't burn. If the fuse
blows when you reconnect one of the red wires then that unit (light) is where
the short is. If the fuse blew with all of the red wires unplugged then the
short is in the harness somewhere.
This is the method to find a short. In a shop we did too much of this kind of
work to use fuses so we would make up a test lead with a resettable circuit
breaker to take the place of the fuse.
Let me know,
Howard
Name: Steve
Subject: 1977 MGB 4 speed - 2nd gear crunches
Question: QUESTION: Howard
I have a '77 stock MGB. 4 speed. It engages 1st,2nd, 3rd and 4th
without problem going up the box. Coming down, 3rd to 2nd is aweful -
unless I double clutch, or slow down, the gear crunches. I believe the 77
has all-gear synchro. Why may this be happeneing and any remedies I could
try??
ANSWER: Hi Steve,
Down shifting is a lost art due to the better synchronizers in newer
transmissions. However, there are things that can go wrong to give you gear
clash as you down shift.
Most common is worn syncro rings.
Usually caused by speed shifting on up shifts and the lack of reving the engine
just as you down shift.
(commonly called double clutching but different than truckers double clutching)
Other causes are,
Dragging clutch. Usually noted by gear clash when setting still and going from
neutral to reverse.
Driver not depressing clutch pedal all the way to the floor on a down shift.
If the gear clash is noted to be excessive cold oil more than after driving for
a while it could be the use of gear oil in the transmission. The older MGBs used
engine oil and when BLM took over MG they recommended gear oil and we at the
dealership were then covered up with gear clash complaints so we switched back
to engine oil. You should read my tech tip on prolonging the life of a standard
trans. http://mg-tri-jag.net/tech4.htm
Howard
---------- FOLLOW-UP ----------
QUESTION: Howard
Thanks! I read the hyperlinked tech report. Helpful. What
'grade' of motor oil would you suggest go into an MG's transmission system?
ANSWER: Any engine oil, 20w 40 works well.
---------- FOLLOW-UP ----------
QUESTION: last question on this - when making the switch from transmission
oil to motor oil should I flush the system or can I just drain out the old
transmission oil and replace with the motor oil?
Answer: In the dealership, we just drained the gear oil out and put the engine
oil in but it did take a few miles of driving with the engine oil to clean out
and dilute what little gear oil was left for the syncros to start working again.
Keep in mind this only extended the life of a syncro, it is not going to make it
new again. It is still important to practice proper downshifting. Besides making
the gearbox last longer there is a side benefit of the professional appearance
of a driving habit and thus bragging rights to friends who don't know how to
"drive" a car and who just aim their car. Not to mention impressing
the ladies with that macho "sports car driver" appearance as opposed
to just a car operator. (that's how I got my wife)
Let me know how it does.
Howard