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Distributor problems

canam1212

Member
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Hi guys, I have slowly been rebuilding my bt7 from the frame up, and I am now trying to start it. The only problem (so far) is I have power going into the distributor but not coming out. I have changed the condenser, the cap, the rotor, the plug wires and the internal wires in the distributor itself . I do get a spark at the contact point but not at the spark plugs. Any ideas ? thanks
 
Assuming that you have it wired correctly per the wiring diagram;
Remove the wire from the distributor cap that comes from the center of the coil. Lay the end near the engine block. Have someone turn the key while you are watching for a spark. If you see a spark then the problem is with the rotor or cap or some of the spark plug wires.
If there is no spark coming from the big wire attached to the coil then suspect the coil.
Also disconnect the white with brown stripe wire from the coil. This wire goes back to the battery switch and many times the battery switch fails and grounds the points " somewhat ".
The " somewhat " may just be enough to prevent a proper spark.
Depending on what style connector you have at the coil for the white/brown wire, you may want to disconnect the white/brown wire at the battery switch instead of the coil connection.

Ed
 
Check the centre contact up in the distributor cap... mine was broken in half. (In the old days we would just 'tug' gently on it to pull out the spring a little bit)....(thats how i found out it was broken in half)?
 
gblawson said:
Check the centre contact up in the distributor cap... mine was broken in half. (In the old days we would just 'tug' gently on it to pull out the spring a little bit)....(thats how i found out it was broken in half)?

An slant on the above is that the centre carbon electrode is stuck up into the cap - easily done, happened to me.
A good chase through the electrics is highlighted in the manual, and you should do it in sequence if you have one.

Checking the coil cuts to the chase, (that test appears at the end of the sequence) but you are not sure if all the othere tests are good, if the coil shows a failure. A variation on the coil test is to turn the ignition on and place the lead from the coil on the engine and just open up the points with a screw driver, assuming that they were closed in the first instance, it should show a spark discharge onto the engine.

let us know how you get on, and if you require the test sequence.

Bob
 
Make sure your points contact is isolated from ground using the little stepped insulating washers on the pivot stud.
 
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