Cracked distributor housing - advice needed

[Ryan_M]

What would you guys do with this?

[athawk11]

Hey Ryan,
IMHO, I don't think that would adversely affect the performance of the distributor.  Mix up a little JB Weld and call it good.

Tim

[BMIC]

Ryan is the gap just the key way to lock the cap in place or is a piece missing?

[scoutpilot]

[size=14]As long as the rotor continues to rotate in a level plane, JB sound like a good idea.[/size][/b]

[1955CJ-5]

I'd sure try the JB as suggested..

There is also a JB-Quick so you don't have to wait forever...force/squeeze it into the crack, the excess can be easily removed  before it sets completely.

[Ryan_M]

I like the way you guys think. JB Weld it is.

And BMIC, the gap is the keyway for the cap. I did have to remove the distributor from the block with a tie-rod separator and a BFH after prolonged CRC Freeze-Off and MAPP Gas treatments failed to do anything. It's a wonder I didn't destroy the thing completely.

[Carls_jeep]

I think you should use an old distributor cap to drive the cracked part back down after you use a two part epoxy in the crack. If you don't it may leave the dist. cap at an angle and could be an issue at some point.

[Ryan_M]

I think you should use an old distributor cap to drive the cracked part back down after you use a two part epoxy in the crack. If you don't it may leave the dist. cap at an angle and could be an issue at some point.

I had thought of doing that but opted against it as I was afraid I'd JB Weld the cap to the distributor. I have the crack JB Welded and clamped back in place pretty well now. We'll see if it holds up. I did notice that prior to this repair the rotor was hitting one of the contacts on the underside of the distributor cap and leaving little metal flakes and wear marks as evidence. I'm not sure if that is at all related to the crack but I'm hoping it will go away now that I have made this repair.

 Waiting on a new carb to arrive so it'll be at least a few days before I can test everything.

[stony]

IMHO, Would look for a new (used) distributor and keep it handy, just in case.....

[Holdmybeer]

X2.  Despite that I share everyone's enthusiasm for JB Weld, I think in this case it's only a good expedient repair, until you find a new/used replacement.  It's not like your glueing on a windshield wiper that you might do without.  When the distributor stops, everything stops.   Murphys Law will ensure that it will fail at exactly the worst possible moment.  Guaranteed.

[Holdmybeer]

X2.  Despite that I share everyone's enthusiasm for JB Weld, I think in this case it's only a good expedient repair, until you find a new/used replacement.  It's not like your glueing on a windshield wiper that you might do without.  When the distributor stops, everything stops.   Murphys Law will ensure that it will fail at exactly the worst possible moment.  Guaranteed.

[Ryan_M]

Ok, can anyone help me figure out what to shop for? Tag is missing from the distributor. This M38 has been converted to 12V but I think there is a 6V resistor on the wire before the coil. Does this mean I should use a 6V distributor?

My working knowledge of mechanics is basic at best. My knowledge of electrical systems is even worse.

[stony]

My knowledge of electrical systems is even worse.

OK maybe I can help you out a little:� First off the 12V or 6V doesn't matter.� The resistor is associated with the coil, and is independent of the distributor.

Now the distributor does two things: it allows the coil to build a high voltage "charge", and when the coil discharges it points the "spark" to the correct plug wire.� The coil is a transformer with two sets of wire windings, a primary (few) and a secondary (many) that steps up voltage.� Basically here is how it works:� A small cam (4 lobes, 1 for each cylinder) on the distributor shaft opens and closes the points as the shaft turns.� When the points close current flows through the coil + through the primary, out the coil - through the closed points to ground.� When the current flows through the primary windings it builds an electromagnetic field.� When the points open the current stops and the field collapses, and the collapsing field creates a very high voltage in the secondary windings (from 6V to 20,000+ v).� This charge flows through the high voltage wire to the center of the distributor cap down into the center of the rotor, where it travels through the rotor and jumps the gap to the plug wire terminal.� Then through the plug wire to the sparkplug.� Each cylinder in its turn.� �To get a little more technical, all of this takes time, so as the engine RPM increases the process of generating a spark needs to start sooner so the the spark gets to the plug at the correct time, so a set of springs and weights advance the timing as engine RPM increases, so you need to make sure they are in good shape too.� There you go, everything I know about points ignition, not too much too it� .

[Ryan_M]

OK maybe I can help you out a little:� First off the 12V or 6V doesn't matter.� The resistor is associated with the coil, and is independent of the distributor.

Now the distributor does two things: it allows the coil to build a high voltage "charge", and when the coil discharges it points the "spark" to the correct plug wire.� The coil is a transformer with two sets of wire windings, a primary (few) and a secondary (many) that steps up voltage.� Basically here is how it works:� A small cam (4 lobes, 1 for each cylinder) on the distributor shaft opens and closes the points as the shaft turns.� When the points close current flows through the coil + through the primary, out the coil - through the closed points to ground.� When the current flows through the primary windings it builds an electromagnetic field.� When the points open the current stops and the field collapses, and the collapsing field creates a very high voltage in the secondary windings (from 6V to 20,000+ v).� This charge flows through the high voltage wire to the center of the distributor cap down into the center of the rotor, where it travels through the rotor and jumps the gap to the plug wire terminal.� Then through the plug wire to the sparkplug.� Each cylinder in its turn.� �To get a little more technical, all of this takes time, so as the engine RPM increases the process of generating a spark needs to start sooner so the the spark gets to the plug at the correct time, so a set of springs and weights advance the timing as engine RPM increases, so you need to make sure they are in good shape too.� There you go, everything I know about points ignition, not too much too it� .

Profoundly interesting. I read through that four times, made one trip out to the garage, and came back and read it two more times. Thanks for taking the time to type it all out.

[stony]

Thanks!  Only one more thing in there, the condenser.  What does it do?  When the coil discharges it feeds a voltage spike back to the points,  The condenser absorbs the spike, otherwise it would arc across the open points and would burn them out in short order.   While we are talking about ignition, in a no spark condition, check for voltage on the coil +, if it is there, look to the points.  Remember coils rarely fail, points fail all the time and are routine maintenance item.  My brain is empty now, time for bed.  Have fun.