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BN2 Won't Start

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Twstnshout

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1955 100/4 BN2: I can’t get it to start.
I’ve had the carbs rebuilt by a specialist,
replaced the fuel pump,
blew out the fuel lines,
had starter and generator rebuilt,
and replaced the coil and original distributor with Pertronix units, and new plugs and wires.

Engine cranks fine. The timing is probably a bit off. The coil and distributor are probably wired incorrectly. The car hasn’t been started since around 1969. I also already reconditioned the fuel tank. Any photo aids to proper wiring would help. Frankly any help would be great.
 
Does the engine start to fire at all? If so, the carb settings are likely off.

Is the fuel pump a SU pump? If so, does the fuel pump tick for a few seconds, then slow down then stop? If not, the pump may not be wired correctly. If it doesn't stop ticking, the fuel line to the pump may have become blocked during the reconditioning of the fuel tank.

You can pull a plug or a plug wire and see if you're getting spark.
 
Your car only needs three things (more or less properly adjusted) to start:

1. Cylinder compression
2. Spark
3. Fuel.

If the engine hasn't been run in over 50 years I wouldn't make too many assumptions about anything.
I'd suggest you first test to see if there is compression on any or all the cylinders.
A basic compression gauge will only cost $15-$20 at your local auto store or online--or you can use a thumb if you're careful.

Report back....
 
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The fuel pump clicks then stops, the car never started before I had any work done I did a compression test on all cylinders there is compression in all cylinders seems a bit low but not terrible. It doesn’t fire at all there is no spark. I quite sure I’ve screwed up the coil and distributor wiring not the firing order
 
Here is a really good explanation of how this all works. If you are getting fuel to the carbs,, and it sounds like you are and have decent compression and it sounds like you do, go with the no spark situation. In all honesty, if I were you, I'd put the points back in and get it running that way. I have had problems with a pertronix set up in my BN2 and have gone back to breaker ignition. I can trouble shoot by the side of the road if needed and carry a set of points, condenser, and a few other bits that are internal to the distributor. Most folks love the electronic ignition and it is wonderful when it works but a mystery when it doesn't. Read this and I'll bet you'll be up and running in no time.

Ignition coil polarity

mgaguru.com
 
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To the OP - take a look at the BCF club page:

Clubs

British Car Clubs around the globe
www.britishcarforum.com www.britishcarforum.com

Each club is a link to the club's contact page. You could connect with someone who can help you face to face.

New Jersey:
The MG Car Club Central New JerseyNew JerseyThe MG Car Club, Central Jersey Centre, Inc. was founded in 1962 to further the interest in the MG marque. Ownership of an MG is not a condition of membership in our Club.
Positive Earth Driver's ClubNew JerseyThe goal of the PEDC is to preserve, maintain, restore, drive, and otherwise enjoy vintage British automobiles.
Delaware Valley Classic MG ClubNew Jersey (and surrounding)The DVC is an all MG club…From Pre-War to MGF Especially the T-Series, MG-A, MG-B, MG-C, and Midgets
Delaware Valley Classic MG ClubNew JerseyIt's not the destination. It's how you get there.
 
T--

Glad to hear you have compression as that would be the most expensive missing ingredient, and next you should test for spark

As you may have read in the article Roscoe cited, even if you have reversed the wiring to the coil that alone would not prevent the car from starting, assuming all else is okay, and before you start replacing ignition modules or going back to points you should determine whether or not your problem is in fact an ignition issue.

You'll need to crank the engine with either a remote starter attached to the solenoid, or a helper to push the start button while you test at each cylinder.

The easy method is to get a tester lead that installs between the end of each plug lead and the plug. There is a clear plastic section and a bulb that will light up--or not--during cranking which will show if power is getting to each plug. Or, you can remove each plug and with insulated pliers hold it close to an unpainted metal surface on the engine while the engine is being cranked to see if a spark jumps from the lead to ground.

If each cylinder does not haver a good spark you'll have to backtrack to the coil and distributor.
 
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If you have no spark at the plugs, check if you get spark from the coil. Remove the coil wire from the distributor cap and hold it close to a ground.
 
John Turney said:
Does the engine start to fire at all? If so, the carb settings are likely off.

Is the fuel pump a SU pump? If so, does the fuel pump tick for a few seconds, then slow down then stop? If not, the pump may not be wired correctly. If it doesn't stop ticking, the fuel line to the pump may have become blocked during the reconditioning of the fuel tank.

You can pull a plug or a plug wire and see if you're getting spark.
Click to expand...
I finally got spark from coil and to the plugs. If I load the cylinders up with either it will start. It won’t run for long a few seconds. There is gas getting to the carbs. I loosened the bolts and turn on ignition switch for a second, gas flows out of both junctions. So hmm these carbs are new to me. I probably need to get the static timing set closer. Any thoughts?
 
Twstnshout said:
I finally got spark from coil and to the plugs. If I load the cylinders up with either it will start. It won’t run for long a few seconds. There is gas getting to the carbs. I loosened the bolts and turn on ignition switch for a second, gas flows out of both junctions. So hmm these carbs are new to me. I probably need to get the static timing set closer. Any thoughts?
Click to expand...
T--

The static timing should be between 5-10 degrees BTDC.
After you adjust timing If it still doesn't start see if the plugs are wet with fuel.
 
In fact they are bone dry. The engine will start in the either but immediately stalls the fuel is getting to both inlets but not any farther.
 
T--

If fuel was getting into the cylinders the plugs should be somewhat wet after cranking without firing. And the fact that the car starts on ether--which I assume you are spraying into the air filters--seems to verify that fuel is not getting into the engine.

I'm not sure what you mean by "inlets"--are you referring to the fuel bowls? Have you taken off the carb domes to see if there is any fuel in the bottom of the carbs?
 
Sounds like stuck float valves. Not inconceivable; rotten/alcohol-laced fuel could have turned the sealing tips into a sticky mess.
 
T--

Looking back at your initial post you said: I’ve had the carbs rebuilt by a specialist, replaced the fuel pump, blew out the fuel lines

Nevertheless, did you check to see if the fuel pump actually works by disconnecting the fuel supply line either at the pump or the carbs?
 
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Yes I broke the line loose at the banjo fittings and turned ignition on for a second fuel spurted out of both. Fuel isn’t getting through from there. I’m watching youtube videos and reading how to adjust and tune these carbs. They’re a different sport from the corvettes I’ve always restored before. Lol
 
T-

Sounds like the problem is in the bowls and as Bob suggested you should pull the lids off and see if the jets are stuck closed or if the forks/floats are jamming them shut.
 
Twstnshout-

Any news? I tuned into this thread as I was going to try to start my "never ending restoration" BN2 this weekend. It hadn't run since October of 2010. Same deal for me, carbs rebuilt, new fuel pump, lines and hoses. Distributor was out and gone through, so I had pretty much no idea on the timing or if it was even clocked in properly. I guess my luck was better as it pretty much started right up after clearing the fogging oil.

One issue I had some time ago on this car was the float bowl vents (if there are any) became clogged or perhaps the wrong top bolt gaskets were used in a previous rebuild or something like that, but the float bowls would become "pressurized" and wouldn't permit a full load of fuel to enter. Now I have the taller top bolt and 100M style drain tubes fitted to vent the bowls, never had another problem with it. Of course, the car ran fine for ~40 years without such vents...just throwing out ideas.
 
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