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MGB How to charge '71 MGB

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Acejam

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Hello all, new to this forum.

I recently received my grandather's 1971 MGB, red in color.

I have driven it a few times around the block and it runs great, for he had an overhaul done on it a few years ago, so it runs fine.

The question I have for you all is the following.
The car has two 6 volt (i believe) batteries behind the 2 seats. I have removed the battery cover thingy, to gain access to them.

I have a maintainer charger thingy, and I want to hook it up to the batteries, so they dont die obviously, but how do I do this with TWO batteries? Any suggestions?

Also, when I fill it up with gas, do I fill up the whole tank and then put it lead additives? Anyone reccomend any types of certain additivies or brands. Thanks!

PS: I've tried seraching but cant seem to find any info on the charging issue.

-Josh
 
Josh,

You only have one battery in your car. True, that one battery comes in two boxes, but it's still only one battery. A single 12 volt battery has 6 two volt cells; your two 6 volt batteries have 3 two volt cells each.

If you were to place the two batteries side by side, glue them together, and make the connection between them internal to the cases, you would have one single 12 volt battery.

In other words, charge them together as if they were one battery and you'll be fine.
 
Ok, so where do I connect my positive and negative cables to then? I was told that I should put the positive cable on the positive terminal on one battery, and the negative on the negative terminal on the other battery. Is this correct?

I just dont wannan screw this up. Thanks in advance!
 
[ QUOTE ]
Ok, so where do I connect my positive and negative cables to then? I was told that I should put the positive cable on the positive terminal on one battery, and the negative on the negative terminal on the other battery. Is this correct?

That is right...just make sure you hook to the terminals which are NOT connected to the other battery. In other words, hook the charger to the terminals which run to the car, NOT to the other battery.

Bruce /ubbthreads/images/graemlins/cheers.gif

I just dont wannan screw this up. Thanks in advance!

[/ QUOTE ]
 
Ok. How do i know which terminals run to the car, and which run to the other battery?

Sorry for being such a newbie, but i'd hate to hook it up the wrong way and blow something, lol.
 
If you can't see which cable goes from one battery terminal to the other, do you have a voltmeter? Measure from one negative terminal on one battery to the positive terminal on the other battery. If you get no voltage, then those are the terminals that are connected together (definitely NOT the ones you want to connect the charger to!). Try the opposite terminals, and you should get 12 volts. Also look for the negative terminal that goes to the car body, that would be the terminal to connect the negative side of the charger to.

-Dave
 
I use "float chargers" on the cars I don't use very often. A worthwhile thing for you to do is mount a non-switched cigarette/utility outlet in your car. Take your float or trickle charger and put a cigarette lighter plug on the end instead of the alligator clips. That way, all you need to do is "plug in" the charger when you want to use it. Remember, this is NOT suitable for high-amp chargers, only trickle and float chargers where the current won't hurt the wires. (If you're worried about being able to use the modified charger later... don't worry. Parts stores sell a harness that has alligator clips and a female cigarette outlet socket. That will allow you to quickly adapt the charger "back" where you can clip it onto the batteries of other vehicles.)

As for the lead substitute/additive, buy Red Line additive, and add it before filling the tank. That way the gas you pump agitates what's in the tank and helps mix things up.

Enjoy your car!
 
Ok, so i was afraid to drive it to the gas station fearing about running out, so i fillled up a 2.5 gallon tank, and put in some lead additive, I belive CD2 makes it. I put approx 1/4 to 1/2 oz of it in, and mixed it with my tank before actually pouring it in, because I only had 2.5 gallons in my portable tank to fill it up with, there was some gas in the car already, but its already mixed which my grandfather did. Also, the gas gauge was below E before i put the gas in. Now its like directly on F, so does this mean the gauage still works? lol

I have a trickle charger, and im going to use that. The cigarette lighter sounds like a MUCH better and easier idea. So all I have to do is buy the end that will clip up to the charger, and then put it in the cigarette lighter socket, and plug the other end into the wall? Im pretty sure it is a trickle charger, so im assuming this wont hurt the lines then. My mom has this trickle setup on her porsche, but I wasnt sure if its the same for MGB's, since she has a newer porsche (99).

Thanks SO much everyone for your help, I really appreciate it.
 
Regarding fuel...

Here is my understanding on fuel: Unleaded gas will reduce the level of lubrication protection your valves and valve seats have against the harmful by-products of combustion. Modern cars that were designed to run on unleaded gas have hardened valve seats designed to withstand the harsher operating conditions. So if you run your MG with straight unleaded, the valve seats will pit and wear more rapidly and the head will need re-building sooner than if the car ran with lead.

When your head does need a rebuild, you can redo the valve seats with modern-style hardened ones as per a new car. My understanding is that once you do this there is no longer any need to run lead in the gas at all.

I run my 1970 MGB on raw unleaded fuel for the following reasons:

1) It has a non-original engine in pretty decent shape that I know nothing about - for all I know it has been re-built with hardened valve seats.

2) Even if it has not been rebuilt in this way, the engine seems to have a lot of life in it and my car is only driven in the summer months. Therefore even if I am reducing the life of my valve seats, I can likely still drive for many years before a rebuild is necessary. To my mind the benefits are not worth the cost and hassle of lead additives.

The other thing people talk about with unleaded fuel is pinging and knocking. In my experience a properly tuned MGB runs fine on raw unleaded mid-grade gasoline. If the car is pinging, move up a grade. My veteran British Leyland-trained mechanic says it is a waste of money to insist on high-grade fuel for these cars - he says they are low-compression vehicles and that modern fuel is much cleaner-burning than it was in the 50s and 60s. His advice is to use the lowest-grade fuel that keeps the car from pinging.

I make no claim to be an expert on this stuff, but I have done a lot of reading and I think there is a great deal of misinformation and folk-wisdom floating around. A quick web search will turn up tons of (often contradictory) info... They just recently phased out leaded gas in the UK so all the vintage car guys over there are having this debate for the first time.

Loaf
 
Loaf's points are good ones. There was a thread here (Triumph section) earlier this month talking about the merits of converting to an "unleaded head". The general feeling was the cost of conversion isn't justified until you are doing an engine rebuild anyway. However, you can extend the life of your exhaust valves and seats by running a quality lead substitute. I run the CD2 stuff you mentioned but I've been told by people who work on engines more than I do that Red Line is better. However, Red Line isn't in my local parts stores!

I'm too cheap to even run mid-grade fuel in my car. I set the timing back to a point where it won't ping unless the car is under severe load... and run regular. I'm not an aggressive driver so this works fine for me.

EDIT: I meant to add a comment or two about the trickle chargers. They aren't meant to be left on a car forever. They are typically a day-or-two type devices. Float chargers on the other hand put out lower voltage (around 13v) and can only supply about 500 mA. They won't damage the battery even if left hooked up all the time.

If you haven't visited/found Harbor Freight yet, go to www.harborfreight.com Watch for their sales, get on their mailing list. They sell their float charger for about $15 (about $7 when it's on sale). They also have a whole series of cheap multi-meters. I carry a cheap one ($3 on sale) in the boot of my car to help troubleshoot anything that happens on the road.
 
So I have my trickle charger setup i think....someone verify this below

it plugs into the wall, then the charger, then the little platsic clip. I then got a cigarette lighter thingy, and wired that up to a positive and negative wire. The end of those two wires is in its on plastic clip thing, so the two plastic clips come together, securing the connection, positive to positive, negative to negative. I then plugged in the cigarette lighter, and then plugged in the charger. The green light on the charger comes on, and says charging.

Will this method work? The chargers is 12 volt, 1.5 amp it says..
 
AJ, DougL has pointed up the limitations of a trickle charger which I agree with 100%.What is required as he pointed out is a Pulse/Float type battery maintainer. I use the Sure Charge IV units.---Fwiw---Keoke
 
One more thing. If you are going to lay the car up for any length of time - like over the winter - it is better to disconnect the battery(s) rather than leaving them on any charger. Chargers always deplete the H2O part of the electrolyte to some extent and, left on too long, can ruin a battery. FWIW,

Guinn
 
Ok, so the trickle charger is working now I think....it lights up as "Charging" so i believe i'm good.

Another quesiton, when I want to fill the car up with gas at the station, do I keep filling it up until the pump stops? Does it work with modern day pumps or do I have to be careful about the gas not spilling out? (of course I put lead additive in first, I believe 1oz for 10 gallons or so)


I think my fuel gauage works ok. Before it was below E, and then i put in 2.5 gallons, and now its like ON E. Anyone else like this with their car?
 
I lost my battery over the winter - it was 4 years old, and I figure that the New England winter finished it off. Next year I'm going to take the batteries out of our "toys" and put them in my basement with a trickle charger.

When I fill mine up (it's a B-GT) I just leave it in until it clicks off.
 
Here is my contribution to this long topic:

Battery:

I have 1 12 volt battery and no system to recharge it. Never had any problems. Even after staying 4 months in my garage at 4 degre celcius comes April and it starts perfectly after a few turns. Spend money on a good battery. and make sure the charging system is working as designed with no leaks.

Unleaded fuel:

When you have the funds invest in a lead free cylinder head. In regards on comments about pinging I have none and I have 170LB of compression on a modified cast iron head.
/ubbthreads/images/graemlins/canpatriot.GIF
 
Turns out the car does have gas, and it is 2/3's full supposedly. Although, it seems the fuel gauage is dead. Any common fixes for these gauages around?

Also, the trickle charger has been plugged in via the cigarette socket. So far it says "charging" but has never gotten to "Charged". How long should it take to charge the battery fully?
 
Try following this link to troubleshoot your fuel gauge. I'm going to guess that it's a crummy connection but, by going through the steps you can isolate the connections, sender (#2 likely), or dash gauge (unlikely).

https://www.mgbexperience.com/electrical/fuel1.html

This is an amazing site covering many aspects of B's. It's easy to follow with links to concepts and schematics.

Good luck!

Adam
 
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