QuestionQUESTION: I was driving it the other day. It has been driven3 times in the last year, but i gave it a good run on Sunday, not a problem except one of the spark leads fell off and caused it to run crap for a little while til i got home and put it back on and it was as right as rain.
Got up monday drove it to work fine, drove home monday night and it just wheezed then banged, backfired like id turned the ignition key off and on again.
Tried to re start it after checking there was fuel in and getting to the carbs via an electric pump(standard???) and nothing, it turns over, but nothing. I took off the dizzy cap and prised the points and got a spark somewhere in there, it was dark so i just left it as i had to get to work. Any ideas please?
ANSWER: Hi Alan. I had this happen to me once. Check the inlet manifold carefully. At each end, there should be a circular core plug. It could be that the engine back-fired, and the pressure in the inlet manifold blew one of the core plugs out.
Look at part #3 in the attached diagram:
http://www.mossmotors.com/Shop/ViewProducts.aspx?PlateIndexID=28996
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QUESTION: Hi Barrie, thankyou very much. I looked at both sides of the manifold and both core plugs in place.
Do you have any ideas as to what to do to to just check everything is ok?
Its ben a while since i worked on classic cars and forgot what i knew!
Thankyou.
Alan
ANSWER: Hi Alan. It could be so many things.
The misfire and the sudden loss of everything leads me to think ignition. A fuel system problem usually causes the engine to gradually lose power and then die.
I would replace the plug leads, especially the middle one to the coil. Also the rotor arm and the condenser.
On an early B there is a thin earth wire inside the distributor, joining the moving plate to the fixed plate underneath. These can fray and break.
Have the points closed up due to wear on the plastic heel?
Inspect the carbon brush inside the distributor cap. Is it still long and springy?
Are the spark plugs clean, dry, and correctly gapped?
Also, I would also do a compression check. All 4 cylinders should be within 10 psi of each other.
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QUESTION: Hi Barrie. thanks very much again for your help Ill check all these tomorrow.
Is there anything i can provisionally do to check the coil is working too. Im not sure how to test the resistance but i have a voltmeter, or if there is an old easy way of doing it and you know that then id be very grateful over just buying a new everything
Thank
alan
AnswerHi Alan. You could test the resistance across the two small terminals of the coil. On a 65 B it should be around 3 ohms. The resistance between the HT terminal and either of the small terminals should also be between 0 and 3 ohms. The easiest test is to remove the distributor cap, turn the ignition on and open the points with a fingernail. You should see a dull blue spark. Or you could hold the HT lead about 1mm away from the cylinder head (with a good pair of insulated pliers) and get a helper to turn the engine over. The sparks should be clearly visible. Wear rubber soled shoes, don't touch anything made of metal, and beware of the high voltage.
