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MGB '71 MGB Won't Start :[

Acejam

Freshman Member
Offline
Hey all,

We have a 1971 MGB. It was my mothers, and it has only 30k miles on it. Approximately 2 years ago, we had it taken to a local shop near us for a major tune up. They did a lot to it including new brakes, tires, spark plugs, wires, etc.

It's been running great ever since. Still have the two 6 volt batteries (we got new ones), and we have it plugged into a trickle charger when not in use.

I used to run it about once a week, if not more. Unfortunately, recently I have been very busy, and therefore haven't run the car in about 3-4 weeks. It has also gotten much colder recently here in Boston.

Yesterday I went to start the car, and it would not start. I tried a number of times, and figured maybe the carb was flooded or something. (I don't know much about old cars :smile:)

Therefore, I decided to wait. I tried again today, but with no success.

The car turns over fine, and just keeps cranking/turning over, but no spark. All lights, and even the radio, still work fine, so it definitely has electricity/power from the battery, and cranks good, it just won't fire up.

I also do not know how much gas the car has, as the fuel gauge does not work. The last time I filled up the tank was a couple months ago, and considering we dont drive it often, it still has summer gas in it. Therefore, I went and put some winter gas in (different vaporization points), hoping maybe that would help with the colder weather. Also added a little bit of STABIL. Still no luck.

I'm thinking about perhaps taking the plugs out one by one, and cleaning them. I know from my building over motor scooters when I was younger that that would often times help with a fouled plug or something along those lines.


Any ideas as to what to try first?
 
When you turn the car on do you hear ticking and then the ticking stops? If so you have gas or at least liquid filling & pressurizing the lines. If it started before it should start again but will take longer seeing is that it is cold up there in Concord. Try again and listen for the ticking. If it stops keep cranking it over with the choke out and she should start.
 
If it doesn't tick at all then your fuel pump has quit, and the points probably need to be cleaned, sometimes it will restart with a firm whack from a hammerto a solid metal part of the pump.
 
Yes, I can hear some type of ticking. Seems like its coming from behind/near the passenger seat, on the right of the car. I hear it when i first turn the key, which I guess would be "priming" it?

Should i try starting it with the choke out? As in, hold it out/pull it out and twist it, while starting? I've honestly never used the choke to start the car, but if i pull it out it will slowly slide back in unless I turn it.

I just don't want kill the starter from cranking it so much.

How much is too much?
 
Oh yeah! Definately try the choke! Once it kicks (we live in hope) let as much choke out as you can while keeping the idle at about 1500 RPM until it warms up. Then let the choke off completely. Running with it on is very hard on the cylinder walls as the extra fuel washes the oil down.
 
Ace, are you certain it has no spark? Have you pulled a plug wire from a plug and tried cranking the engine while holding the end about 1/4" away from the cyldinder head, or other good ground? If you don't get a spark to jump that gap, forget about all the fuel related stuff and start electrical troubleshooting.
Jeff
 
I do not know if it has a spark or not. The car used to run flawlessly, and then 3-4 weeks later it no longer starts.

I've never tried to start an engine with a spak plug wire off a plug. Is there any easier method?
 
Whoa! you don't want to try to start the engine with a plug wire off without preparation.

First, get someone to help you. Remove a plug wire at the plug. Make sure the car is in neutral. NOW hold the plug wire near a steel part of the engine and have the helper crank the engine over several times. You should see a spark each time it turns over completely.

Assuming there is spark, replace the wire, pull and hold the choke out, open the throttle a bit and crank her over. It should start.

Remember that an engine that has been running needs is fuel (pump clicks) air and spark at the right time.

Guinn
 
Just a thought. Try a set of new/clean plugs. It worked for me this week when all else failed...

Newkie

P.S. Either way, good luck.
 
So why aren't we using the choke? /bcforum/images/%%GRAEMLIN_URL%%/yesnod.gif As in "pull out and twist to lock...

I live in sunny So. Cal and I need it to start. I'd be surprized if it would fire in Boston right now without it!

If it still won't go, then chase the spark.
 
So, in case all the different advice above has you confused, let me distill it down to the steps I would take, in order:

1. Make sure the ticking noise (fuel pump) stops after a few seconds. If it doesn't, you are probably out of gas.

2. Use the choke. Pull it out most of the way and twist. I bet it starts right up. If you've never had to use the choke before, I'd guess that the mixture is adjusted too rich and should be leaned out for economy, performance and engine life. Don't forget to push the choke in as the car warms up.

3. If that doesn't work, check the spark as Guinn above suggested. If I were you I'd grab the spark plug wire with insulated pliers or poke a plastic-handled screwdriver up into the plug boot and make the spark jump from the screwdriver shaft to a head bolt, making sure that your body does not form a more convenient path for electricity flow to the chassis or engine. Look for loose connections if the spark isn't there.

4. If none of those things works, come back and talk to us.


Oh, one more thing. If that 30,000 mile '71 MGB still doesn't start, give me a call, I'll take it off your hands for a very small fee. /bcforum/images/%%GRAEMLIN_URL%%/wink.gif
 
Just tried using the choke on the car, and still no luck.

I got out a flashlight and inspected the engine bay some more. This time, i found a bunch of acorn nuts, some half eaten/open, stashed in the right corner. Therefore, I think there may be some chipmunks or something of the sort, that perhaps has been doing some chewing of wires.

Although all electronics still work, including all lights, and even the radio.

Maybe their is a chipmunk stuck in the intake? haha


Its to the point where it keeps turning over, but just won't fire. I'm afraid to keep holding it, as I don't want to kill the starter. It still does click, makes a couple clicks, stops, then some more. That sound normal? (fuel pump noises)

Also, I noticed there is an inline, what looks to be, fuel filter on the right side of the engine bay leading to the carb. The filter seems to be filled only halfway with fuel, does that sound right?


Thanks for all the help guys, I really appreciate it. I myself am used to working on my 320whp Subaru STi, so this is a bit out of my league.
 
OK, you know what to do next. Next step is to figure out whether this is an electrical or fuel problem. Check the spark before you run the battery down any further. You'll need a helper to crank the car while you hold the screwdriver/pliers. Also, do a visual inspection of the coil and distributor (coil is bolted to the passenger side of the engine bay towards the back) to look for chewed or disconnected wires.

The MG is dramatically less complicated that the Subaru, so this should be way inside your league.

Oh, by the way, I think you have your left and right switched. When we speak of left and right in automotive parlance, we are referring to which side is your left or right while facing forward, seated in the drivers seat, not while looking into the engine bay. Therefore the fuel filter you spotted is on the LEFT side, not the right.
 
I will try this soon.

Also, I might just take out the plugs for the heck of it, and clean them/get rid of any carbon, and then try again.

When taking the plugs out, should I worry about disconnecting the batteries at all for safety? I plan to just take the spark plug wire boots off, and then take the plugs out.
 
Acejam said:
Thanks for all the help guys, I really appreciate it. I myself am used to working on my 320whp Subaru STi, so this is a bit out of my league.

Shoot, I bought my MG because I get the feeling I'll wreak untold carnage, every time I muck about with my Subie (2003 Legacy Wagon).

The last car I felt safe working on was my '76 VW Rabbit.
 
Acejam said:
When taking the plugs out, should I worry about disconnecting the batteries at all for safety?

Not really necessary. The plug wires aren't connected to anything inside the distributor. No way can 12v jump the gap.

If you want to play it safe, just disconnect the small wire between the distributor and the coil.
 
There's a lead connected to the distributor right?
On my Midget it has a habit of falling off, it connects via a spade lug. Vibration works it off, then the car acts just the way you describe.

I agree with Davester - narrow it down, I would check electrical first.
 
Was going to ask, is there power to the Dizzy. That single wire spoken of above. If I was a chipmonk I would like that one.
 
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