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MGB Doesn't Start


Kite
10-13-2007, 01:06 AM
I am a newbie and I just bought my first 1980 MGB. I test drove this car 3 times before purchasing it. Everytime there was a little trouble starting it and it ran great. The first time trying to start it on my own, the engine started normally. Then, as I backed out of the driveway I didn't give it enough gas and the engine died. I haven't been able to start it since then. The engine always turns over great and the new spark plugs are firing.
What is the best steps to take in diagnosing the problem / and finding the solution?
Thanks for any advise-

ScottB81
10-13-2007, 07:43 AM
What is the best steps to take in diagnosing the problem / and finding the solution?

I like the way you asked - you didn't ask what the problem was, you asked for help in diagnosis and finding a solution.

I haven't had an MG for long, but the best sources of information by have been the user groups and various websites. The MG-MGB group on Yahoo, and the MGS forum on autox.team.net are two excellent resources. Those are good, along with the many websites of clubs and people with particular interests.

This is an interest that is made for people who are willing to help each other out. Because of that, there is absolutely gigabytes of information out there. I've collected about 3.7GB myself. After that, getting your hands dirty and doing a little exploration helps with familiarity.

Myself, I now have the requisite three MGB's - one to dream about restoring some day, one to drive and keep up my enthusiasm, and one for parts and for experience in how things come apart and go back together again.

I hope this helps

djamnicki
10-13-2007, 08:05 AM
You said the engine turns over so its not a starter prob. Spark plugs fire but at the right time? Check compression (timing gear prob)and fuel pressure/volume.
The MG cars were great. I had a 1962 MGA 1600 MKII convertible,exactly the same model Elvis drove in the movie "BLUE HAWAII". It had an electric fuel pump located behind the drivers seat on it died on me and it was the set of contact points in the pump. I took my sneaker off and tapped on the pump to get it to work and luckily made it home.
They have as many probs as other British cars but are so much fun that they are worth it.
I hope you find and fix you problem soon and it doesn't cost much.

Kite
10-13-2007, 12:38 PM
Thanks for the input. Just to give an update - I pulled the gas line off the carburator and put it in a coke bottle and turned the key enough to hear the fuel pump. Plenty of gas went into the bottle. I think the fuel pump works great. When I do try to start the car, it sounds as if it is either flooded or not getting any fuel at all.
I am going to do some research on this "Check compression (timing gear prob)"
Any suggestions for what to check next is very appreciated.
Thanks again

Kite
10-13-2007, 05:39 PM
Here's another update - This afternoon, I fixed the gas gage indicator, the radio, and I think I fixed the heater. I can't test the heater because I still can't start the car. I think I am too ignorant to diagnose the problem so I am going to pull it to a garage when they are open on monday. Hopefully they will identify the problem. Its too bad because today was perfect MG weather.

Kite
10-14-2007, 12:40 PM
I am still looking for any advice that you all might have. Last night I pulled out the Carburetor. I took it apart cleaned it up and put it back together without any problems. When I put it in the car and tried to start it up, it almost started twice. It sort of seemed as though it wasnt strong enough to really fire up. After 5 mins or so it was right back to the original problem of turning over great with but nothing close to starting.(maybe flooded).
Does this sound familiar to anyone else.
What is to blame? carb?

What should I look at next? Maybe its the distributor?
Thanks ahead of time

Flash75
10-14-2007, 06:46 PM
You said the spark plugs are firing. If they are the distributor is probably OK. You really need to go through a complete tune up to determine the health of the engine. Adjust the valves, you have new plugs. Check the compression. The compression should not vary more than 15% from cylinder to cylinder. Typical compression for your engine should be around 130-140 psi. Turn your number one cylinder (the one closest to the radiator) to top dead center of the compression (TDC) stroke (both valves will have clearance) and note the direction the distributor rotor is pointing. The plug wire over the rotor should go to the plug in #1 cylinder. Firing order is anti-clockwise 1, 3, 4, 2.

You mentioned you cleaned the carburetor, but you don't say what carburetor is on the car. If it is the original ZS the choke and a split or damaged diaphragm can cause problems, Here are two links that should help if you have the ZS.
http://www.theautoist.com/zs_water_chokes.htm
http://www.paulbunyan.net/~jasko/choke/

You don't mention if you have a repair manual, you should have at least a Haynes repair manual. They can be ordered through various sources, try Amazon.com.

Good luck, Clifton

Kite
10-15-2007, 12:32 AM
Thanks a lot Cliff. I work on it a bit longer tonight and with the help of a friend we took a few steps forward. In fact, we were able to get the engine running(kind of). We decided to check the plugs again. As I turned the key, he took the #1 spark plug cord and put it up to the engine to get a spark. As he was holding it there, the engine started on the other 3 cylinders. So I am going to do a bit of research about the distributer and adjusting it. And make sure the correct lines are running to the correct plugs. Also, I will look into the compression.
Thanks again

Kite
10-15-2007, 12:34 AM
Sorry Clifton, I called you the wrong name in the last post.

djamnicki
10-22-2007, 08:21 AM
Thanks a lot Cliff. I work on it a bit longer tonight and with the help of a friend we took a few steps forward. In fact, we were able to get the engine running(kind of). We decided to check the plugs again. As I turned the key, he took the #1 spark plug cord and put it up to the engine to get a spark. As he was holding it there, the engine started on the other 3 cylinders. So I am going to do a bit of research about the distributer and adjusting it. And make sure the correct lines are running to the correct plugs. Also, I will look into the compression.
Thanks again
You may be on the right track! A bad grounding plate in the distributor may be the prob.

jdemgb
10-28-2007, 10:48 PM
Kite, did you get your problem fixed? Did you check the diaphragm as Clifton suggested. It sounds like thats the problem. Also, when you reassembled the carb did you make sure the diaphragm nipples were in the correct places in the piston and carb body. They orient the piston in the proper direction.

If the diaphragm is bad or oriented improperly, then you need to clean the plugs - they will be fouled, which may cause a cylinder not to fire.

Kite
10-28-2007, 11:22 PM
Sorry that I haven't posted. Here is my update. I am sort of new to MGs and I didn't know this was even possible, but the problem was that the gas was really old. I had some friends take a look at it. They were puzzled, but they thought the gas smelled a lot like varnish. I eventually took it into a garage to have the timing checked out and it was right on. The compression was right on. Anyway, it turned out to be the gas. Now it is running great on all 4 cylinders. I also got my Haynes manual in the mail. So now, I have a bunch of other projects to fix with the electrical like blinkers and the tachometer.
Thanks for all the help.
Aaron

jdemgb
10-29-2007, 11:29 PM
Great news! Have fun!

gerrym
11-30-2007, 03:07 PM
Been Reading On Your Problem And Maybe I Can Help.

First Pull A Plug After You Try To Start The Car. Wet Or Dry?

You May Also Have A Vacuum Leak. Sucking Air Into The System Not Allowing Gas To Get Into The Cylinder. Check All Hoses And Around All Gasgets While Cracking The Car. Listen For A Difference.

KimMG
12-01-2007, 11:10 AM
Fixing electrical problems aren't too difficult, just tedious. You will need a multimeter or a test light and a copy of the wiring diagram. The Haynes diagrams aren't the best, too many years combined into one and there are errors. For a wiring diagram, go to http://www.advanceautowire.com and click on "stock schematics". Use the page for '78 and later from Bentley. Make yourself a couple of enlarged copies, one for reference, and one to make notes on as you check the circuits. Most electrical problems are caused by dirty, corroded connections. Bullet connectors and sleeve connectors are available at www.britishwiring.com
Dan Masters has instructions for installing bullet connecters on his site, http://www.advanceautowire.com click on "instruction manuals" then click on "headlight relay kit".
"The fuse is fine" is a common phrase I hear. There will be nothing wrong with the fuse, but the problem will be corroded contacts in the fuse box. Use your meter or test light to check for power at the wire terminals going to various components in the circuit you are checking.
After checking for power, check the ground connections, making sure they are clean and secure. Use dielectric grease on connectors you have cleaned to prevent future corrosion.
http://www.mgexperience.net and http://www.britishcarforum.com are both excellent sources for technical articles and names of different parts suppliers.

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