• Hi Guest! Being a Paying Supporter is NOT a requirement to participate at BCF. However, subscribing will help ensure we can continue to serve the LBC community for years to come. If you enjoy BCF and find our forum a useful resource...Please consider supporting us by **Upgrading**
    (PS: Subscribers don't see this banner)
Tips
Tips

MGB Awakening grumbles.

WillR

Jedi Warrior
Offline
though i had planned on putting an aux pump in to keep as a back up for long term then getting around to rebuilding my su, i got to excited and picked up a new su pump from a local guy. Replaced and pumped the old gas through the lines and in to a can while i brought up my oil pressure. (Ignition unplugged.) I was feeling pretty good as the needle climbed right up to 75.

Put some new gas in and she started up with little hesitation. Brought a big smile to my face. Soon as the oil was warm swapped it out with some fresh and got in to the nitty gritty details that reminded me why I put the B to sleep in the first place.

Hazards flash quickly at first but within a few blinks calm down and stay steady. lights and brights work but i have no reverse and at best a few random flashes for turn signals. My tach oddly works as a low voltammeter. the needle buries itself when ignition is on. with the starter engaged it will hover around 3 or 4 then shoot back up. with the turn signal flashing the tach will drop to 4 0r 5 in sync with the signal. All things considered the number three fuse seems a likely culprit. The back of the fuse box itself does little to reassure me of its effectiveness. measuring resistance the needle danced very similar to the tach. corrosion seems to be deep in the copper rivets and i have little luck in my attempts to clean them have i found the lucas demon hunting my B? Is a new fuse box in my future?
Bcf bike and mg.jpg Holy crap after years of fiddling i have actually put a picture on the internet!!!! This is an old shot as i had little hope of figuring this out so i took no new ones of todays progress. That was taken weeks before i put my car away.
 

Sarastro

Obi Wan
Gold
Country flag
Online
Well, you could go through each circuit and troubleshoot it, but it sounds to me, from your description, like you need to go through all the electrical connections, grounds included, and clean them up and make sure they're OK. In these old cars, it's not unusual for corrosion to creep up inside the wires. This isn't, by itself, a problem unless they are badly corroded, with green copper oxide and all that. As long as the connection of the connector to the wire (if any) is clean and the mating connectors are good, the connection will be OK. To clean the wires, spread out the strands and scrape with a pocket knife. Then spread them out differently and do it again until the wire shows bright copper over most of each strand. If the connection is one where you screw a screw down onto the wire, be sure the screw connection is clean. If it has a 1/4" spade connection, it might be a good idea to replace the connectors if they are questionable. I like to solder them and use heat-shrink tubing over the connection, but crimp connections are OK too.

Plated or galvanized connectors, like the ubiquitous bullet connectors used in LBCs, are best cleaned with a pencil eraser. Don't sand them, or you will remove whatever anticorrosion coating is left. Make sure the wires are tight inside them and that they fit tightly in the mating piece.

While you're at it, make sure the sockets for the bulbs are clean and so are the bulbs. Bulbs are cheap, so the easiest way to be sure they're OK is just to replace them. Sometimes there can be an intermittent break inside the bulb's base, and it will drive you nuts trying to figure out what's going on.

You might be able to find new headlight connectors and bulb sockets that fit the MG (or can be made to fit) at your local auto store, if you need to replace them.
 

PAUL161

Great Pumpkin
Silver
Country flag
Offline
Will, The in line female bullet connectors become weak over time and it's difficult for a good connection, their not that expensive and Moss sells them by the bag full, I'd change all of them and you'll be good for another 40 years! PJ
 

DrEntropy

Great Pumpkin
Gold
Country flag
Offline
Paul's right about the female Lucar connectors. Over time (and with corrosion and resistance) they embrittle and can break.
 
OP
WillR

WillR

Jedi Warrior
Offline
man oh man i had a goal of finding each connection and cleaning it out before the drive. probably my most dreaded chore for this car. i have a thought to face fears and use the advanced auto wire kit this winter. though i had hoped the fuse box was my problem. i keep pretty busy with some retaining walls im working on but plan to hit the wiring hard this week. i have a plotter size print out of the harness it just doesn't tell you right where the connections are i think ill have to count them tonight so i have a rough idea of what im looking at.
thanks for the advise ill keep the forum posted
 
OP
WillR

WillR

Jedi Warrior
Offline
i knew they could get corroded and make a crappy connection i didn't know they would become brittle and break.
 
OP
WillR

WillR

Jedi Warrior
Offline
If the connection is one where you screw a screw down onto the wire, be sure the screw connection is clean.

what connections have a screw through them do you know an example off hand? From my count there are 74 connections and 56 grounds needing my attention. OCD don't fail me now
 

DrEntropy

Great Pumpkin
Gold
Country flag
Offline
i knew they could get corroded and make a crappy connection i didn't know they would become brittle and break.

On a number of cars through our shop the connectors have crumbled like soda crackers. Used to keep a box of both the single and double ones on the shelf.




what connections have a screw through them do you know an example off hand? From my count there are 74 connections and 56 grounds needing my attention. OCD don't fail me now

Your car is "new" enough that I don't think you have (m)any of these. Some older models had them at the voltage regulator, no MGB I ever saw had that setup. Can't off-hand remember any bare wire connections on a B. Especially not after 1974 production.
 

Sarastro

Obi Wan
Gold
Country flag
Online
I know it's a tedious job, but if you do it well now, the car will be good for another 50 years. I don't know if you will be good for that length of time though; I know i won't be.

Those bullet connectors are, to use the precise technical term, trash. You might want to consider some new connectors. You can get similar connectors at your local auto store, crimp-on, which are probably a good notch more reliable. But if you decide to keep the bullets, just replacing them should be OK as long as you are careful to install them well. The key is to have good clean, tight connections.
 
OP
WillR

WillR

Jedi Warrior
Offline
I like the idea of cleaning / replacing and soldering new connections. Tedious? Yes it would seem very much so. However, Doing a good job now while my car is on stands and i have cover, a good drop light and a house to run and hide in when i hit my boiling point seems a lot more inviting of a situation then what my imagination lets me believe will happen in the middle of a freak blizzard halfway across the country late at night when my connections will inevitably decide to act up. :crazyeyes:
When this process was first mentioned i was just overwhelmed. I took some time to trouble shoot my rear running lights. Tore into the rear wiring a bit and feel like I have a good idea what is needed. Thank you.
The local LBC shop has memorabilia and old parts hanging all over his front and he showed me an old bently fuse box that had all screw connections. Almost scary looking. At some point they got rid of those as i don't have any. Doc i was always amazed when i would read a random question about the location of some obscure part on a specific model and the next post would be your directions in finding it... in back reading of this forum i have learned you worked at a LBC shop and are not employing black magic as i have previously suspected... :devilgrin:
 

drooartz

Moderator
Staff member
Gold
Country flag
Offline
No need to fear the cleanup process -- it's more tedious than difficult. Put on some tunes on the shop radio, grab the rolling stool, and work your way around the car.

First job I ever did on my previous Bugeye (admittedly a simpler wiring layout, but not by a whole lot) was to completely replace the wiring harness. Took a weekend because I'd really never worked on an old car before. A few evenings and you'll not only have the wiring in top shape, you'll know the car that much better and have that much more confidence in the car.

Good luck!
 
OP
WillR

WillR

Jedi Warrior
Offline
Out door gravel driveway is the closest thing I have to a shop here. I at least have an awning to be under. From what i found last night its nothing to be scared of. The formidable unknown is what was getting to me. As of late I took out my Fuse box and gave it a good cleaning. when it was all hooked up correctly my running lights worked flawlessly (big improvement) the front left indicator and running light went from faint glow to strong, and my brake lights light up consistently. :cool:Whoo hoo!! When i tested my indicators they both worked though a new "development" came up. right side lights up in unison, left side had front and back flash alternating. how does cleaning the fuse do that? I know im getting stronger power through the whole car as the head lights are brighter as well as the running lights and my tach, (though not fixed) has less of a drop when something like the blower fan is turned on. i still havnt got to all my grounds yet has any one experienced a tach acting like a voltmeter?
 

drooartz

Moderator
Staff member
Gold
Country flag
Offline
The formidable unknown is what was getting to me.

I know exactly what you speak of here. I faced that when I started on my first Bugeye a few years ago -- never had done more than some basic motorcycle maintenance before and diving into this was a bit unnerving. The more of these projects I did, the more confident I got that I could dive into the next one and come out the other side. Keep at it and you'll feel better about tackling the next project.
 

DrEntropy

Great Pumpkin
Gold
Country flag
Offline
Doc i was always amazed when i would read a random question about the location of some obscure part on a specific model and the next post would be your directions in finding it... in back reading of this forum i have learned you worked at a LBC shop and are not employing black magic as i have previously suspected... :devilgrin:

It's half-n-half, Will. :smirk:

left side had front and back flash alternating. how does cleaning the fuse do that? I know im getting stronger power through the whole car as the head lights are brighter as well as the running lights and my tach, (though not fixed) has less of a drop when something like the blower fan is turned on. i still havnt got to all my grounds yet has any one experienced a tach acting like a voltmeter?

Check and clean all the grounds. The rear one is inside the boot, usually on one of the license tag fasteners. As for the tach, have you got a VOM? Check the voltage regulator on the drivers' side under dash, on the firewall near the steering column. It should be delivering 10V. If higher, replace it or dig thru the articles here to find Doug Lawson's schematic and article about replacing it with a solid-state version.
 

DrEntropy

Great Pumpkin
Gold
Country flag
Offline
And it wasn't just LBC's. I've had Porsche-Audi factory training/certification and went thru the ASE certification process back when it was "NIASE."

...that an' a fin will get me a coffee at FourBucks... :smirk:
 
OP
WillR

WillR

Jedi Warrior
Offline
Thanks for the lead. iv been to engaged to get in the car the last few days put plan on playing in it for the majority today. Tough life :smile: the rear ground looks pretty spiffy now. how in the world do you get to the connections in the front. they seemed buried behind the headlight and blocked to my entry by the pieces of metal behind the light. im guessing there is no trick i can use to get to them? just old fashion busted knuckles.
 

Sarastro

Obi Wan
Gold
Country flag
Online
Can you get to them through the wheel well?

Or, there might not be a ground back there--in my Bugeye, the headlights' ground wires went all the way back to the firewall and were grounded there to a single bolt. I've never worked on an MGB, so I don't know for sure how they're set up, but lots of cars use a single-point ground like this.
 
OP
WillR

WillR

Jedi Warrior
Offline
that would make sense the boot has a ground bolt like that. I have yet to find the ground for up front. yesterday was on and off fat cold rain so i didnt get out to it. the female spade that attaches to the ignition on the starter. its unlike any iv seen. has a knob on top that locks it in to place. who carries this. im getting some funny looks at part shops. as i tried to clean it up it crumbled off the wire.
 
OP
WillR

WillR

Jedi Warrior
Offline
ok some clearification. behind the headlight was way off. i dont know what i was thinking. next to the horn on the sides of the electric fans. i must have been getting frustrated as i can get to them when im fresh. though i still dont see any grounds there.
 

DrEntropy

Great Pumpkin
Gold
Country flag
Offline
The black wires are ground on a B. On a '78 I can't be certain but with the pre-74 cars the wiring for the front lights has a group of Lucar connectors under the "pan" holding the hood release latch. You could add a ground lead at about any of the threaded fasteners already there and plug it into the unused fourth hole of the Lucar ground wire connector.
 

Similar threads

Top