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General MG 77 MG no start

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Svcmangler

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Good morning everyone, the engine turns over. I have spark and fuel. I am suspecting a relay. Any suggestions on where else to look?

What is the correct firing order? I did check the crank pully but can't find any timing marks, any suggestions regarding that?
 
Good morning and welcome to BCF!

Firing order is 1-3-4-2. Assuming you have an original engine, the timing pointer on an '80 B is on the left side of the timing chain cover as you're looking down at the crank pulley. There are five pointers; the one on the far left is TDC; others are 5-degree increments denoting settings before TDC. The pulley should have a groove on both flanges to line up at whatever setting you choose.

Here's a good discussion and depiction of the timing marks' locations: http://www.mgb-stuff.org.uk/tm.htm

As for why it's not starting, so many possibilities. Do you have a service manual? Haynes is pretty helpful.

Keep us posted on your progress.

:cheers:
Mickey
 
SVC - welcome to BCF. When was the last time the engine ran?

Also, turn on ignition, crank a few seconds, turn off ignition. Pull a plug and see if the tip is wet and smells like gasoline. If it's wet, and you have spark, then the engine should run. So we're trying to see if the fuel is actually getting into the cylinder.

Another basic question: does the car have the original carburetion? or electronic? or ...?

Tom M.
 
So the car has sat for over a year without running. I put a new battery in it, pumped the crap out of the gas pedal, and she fired up. I wasnt expecting it, so i let it run for a couple minutes and then turned if off. The next day I went to start it and it wouldn't start. Just cranked. I did pull the spark plugs and they had gas on them, as well, I checked for spark, which I had. It has a carburetor. Not sure if it is the original engine or not. There is a number on the block, but it does not match the number on the drivers door post, or the number on the radiator support bracket. Does that mean it is not the original engine? Should all the numbers match each other?

I have looked at the crank and there is a small hole on it, which I am guessing is the timing mark.
 
Bad gas? Car sat for a long time. Water (condensation) could also be a problem.
 
I took the air filter off and sprayed some ether directly into the carb. I would have thought that would at least getting running for a second. Could any of the relays on the side wall be a problem?
 
OK, my error above - yours is a '77 - still the same as an '80. As for engine #, it will be different than the VIN on the door post or the body number near the radiator; it should start with 18V, per the chart here: https://mossmotors.com/mgb-vin

Timing mark on the crank is a groove on its pulley's inside flange edge, as shown in the link I posted above.
 
As the old saying goes, if its got spark and its got gas and they both get there at about the same time, its got to run. Does this MG have SU or Zenith carbs? If so, pumping the gas pedal means nothing since they don't have an accelerator pump. Don't bother. Are you pulling out the choke cable when the engine is cold? Did you actually spray starting fluid in and it failed to start? Are you sure there's a good spark? Check the points. The gap should be .012 to .015 and check for spark by leaving the ignition on and pushing the points open with a screwdriver - there should be a spark. Timing? If nobody messed with it, it's most likely not that. It may not run good but it'll start unless its way out which is doubtful. Don't go crazy. Do one thing at a time to eliminate possible causes. You'll find it sooner or later.
 
Do what PDPlot says!

Also, the engine started and ran first time you tried. But after sitting, it would crank but wouldn't run.

Check for a loose wire at the coil, or ground strap.

Tom M.
 
Svcmangler said:
I took the air filter off and sprayed some ether directly into the carb. I would have thought that would at least getting running for a second. Could any of the relays on the side wall be a problem?
Click to expand...

Nope. If the starter relay was bad it wouldn't crank. If the ignition relay was bad you wouldn't get any spark.
 
2 questions.

1. what do the plugs look like?

2. Whereabouts in Toronto are you?
 
The plugs were wet, but looked ok. I dryed them, cleaned them and put them back in. I took the cap off and had a look inside and did see two of the contacts were pitted. As well as the rotor didn't look great. I am going to replace those and then see what happens.

I am in Holland Landing, which is about 3 minutes north of Newmarket. Hbu?
 
Svcmangler said:
The plugs were wet, but looked ok. I dryed them, cleaned them and put them back in. I took the cap off and had a look inside and did see two of the contacts were pitted. As well as the rotor didn't look great. I am going to replace those and then see what happens.

I am in Holland Landing, which is about 3 minutes north of Newmarket. Hbu?
Click to expand...

I am in Etobicoke - - Keep us posted re the rotor!
 
JPSmit said:
I am in Etobicoke - - Keep us posted re the rotor!
Click to expand...

So I got it running with the new Cap and Rotor. She does have a little bit of a stumble to it, but nevertheless she is running. I think the idle is set a little low, so will need to check the timing and reset the idle speed.
Thank you everyone for your suggestions. I greatly appreciate it.

John
 
great news!
 
Good morning everyone, I decided to check the points this am and discovered they were a little pitted. I know from past experience they can cause a stumble in the engine. I am having difficulty finding points for this car and I have noticed some suppliers are offering electronic distributors instead of the points and condenser distributor. Does anyone have any experience with them?
Also how can I determine what year the engine I have in my car is from? It does not look original. All of the pollution control stuff has been removed and other things look hap-hazardly installed.
 
Svcmangler said:
Good morning everyone, I decided to check the points this am and discovered they were a little pitted. I know from past experience they can cause a stumble in the engine. I am having difficulty finding points for this car and I have noticed some suppliers are offering electronic distributors instead of the points and condenser distributor. Does anyone have any experience with them?
Also how can I determine what year the engine I have in my car is from? It does not look original. All of the pollution control stuff has been removed and other things look hap-hazardly installed.
Click to expand...


Points vs. electronic. Personal choice here: Stick with the points. Lots of arguments pro/con, but for me the bottom line is that if stranded on the road, issues with points are more easily remedied.

As for engine year, look on the ID plate on the block between #2 and #3 cylinders, near the head.

WP_000360.jpg

If that's missing, there's a "clock" located on the same side of the block, near the oil pan that can be read to determine date of build.

blockdate1.jpg

Have a look and let us know what you find.
 
Good morning and Happy New Year to everyone. So I was able to clean the gunk and spray paint off the block so I could see the date code. Now how do I read it? I have attached the date code and the engine serial number.
engine date code 3 a.jpg
Engine date Code 2a.jpgI am trying to buy a set of points and condenser for it, but when I talked to the local parts supplier, he said there was no listing for points on a 78 MGB. It stopped at 76 MGB, and 78 had electronic ignition. So obviously started me to think that this is not the original engine.
 
I may be mistaken, but the gold paint leads me to believe that's a Gold Seal engine; factory reconditioned. Looks like the "clock" designates 24th week of '78.

Points-type distributor may have been installed.

Did you locate the tag riveted to the block I mentioned earlier?
 
Mickey Richaud said:
I may be mistaken, but the gold paint leads me to believe that's a Gold Seal engine; factory reconditioned. Looks like the "clock" designates 24th week of '78.

Points-type distributor may have been installed.

Did you locate the tag riveted to the block I mentioned earlier?

Thought I had sent it.

The number is 18V 892AE L 002104
Click to expand...
 

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