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Ignition system help

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lushka16

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I have twin 454 Crusaders that need some ignition work. Just to get it out of the way - an electronic ignition conversion is just not in the budget right now :)

I'm having spark issues on my stbd engine. It appears that my coil is just fine, so I'm looking at cap/rotor/points. Replacing the cap and rotor is easy enough, but I have no idea how to do points. I can put it in, I know how to adjust the gap, but I feel like there are steps I'm missing.

One last question - what is this thing, and is it supposed to be piping hot?

IMAG0002.jpg
 
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The item in picture is a ballast resistor, used to limit voltage thru points and coil. It its hot, possible short to ground, or coil is going bad. I'm not a big fan of ballast resistors and usually remove them and use a coil with resistance built in. Seems to be stock coils are weak at best, I usually swap out with a "hotter" aftermarket coil ie Accel, msd, etc.
 
Agreed.... that is your ballast resistor.
The resistance will cause it to heat up some!
While the one that you show uses push-on terminals, I think that we should be using screw down for our purposes.

1279600498.jpg

Your call!
Just keep an eye on the terminals!


Setting contact points:
Gap is an estimate ONLY of correct and proper dwell.
Points should be set using a dwell meter, not a feeler gauge, IMO.

If your Stbd engine is RH Reverse rotation, the distributor shaft rotates the same as your Port side distributor.... however, with the different gear cut, the shaft undergoes a downward load which requires thrust surfaces that counter this downward force. This may be causing excessive wear to the shaft components.
If a constant dwell cannot be maintained, this may indicate a worn distributor shaft.
Inconsistant dwell will cause performance issues.

(Std LH rotation engine distributor undergoes an up-lift force... countered by well designed thrust surfaces)


If you are near a shop who has an old school distributor machine, it may behoove you to have them set this up, and check everything out!
Many that do this work, are also set up to install new bushings.
They'll need to see your OEM advance curve..... and make darn sure that your Port ignition system is offering the same curve/limit as your Stbd side.

There is a pair of YLM 624's .... both an AV and a BV on e-Bay right now and he's offering free shipping.
Given that this would put an end to any future headaches, it may behoove you to purchase them!

$(KGrHqQOKnME2di!FlERBNzT+B4B)g~~_12.JPG

These are VR triggering with mech advance......... no Photo Eye.... no Hall Effect!

Apparently Mallory had a recall on some of the YLM units, and refurbished them.
With full disclosure, they cannot be sold as NEW!
Several poeple, including myself, have purchased several of these, and they are indeed new.... never installed!

.
 
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Ricardo; beware, the 454's use the exact same distributor port and starboard; distributors turn the same direction. I definately agree with the process of using a dwell meter. Small gap changes make for large dwell changes. Normally, a ballast is too hot to touch and not get burned.
 
diver_dave said:
  1. Ricardo; beware, the 454's use the exact same distributor port and starboard; distributors turn the same direction.
  2. I definately agree with the process of using a dwell meter.
  3. Small gap changes make for large dwell changes.
  4. Normally, a ballast is too hot to touch and not get burned.
Click to expand...
  1. Yes.... even with RH/LH rotation engines, the oil pump dictates that both ignition distributors rotate CW. The hypoid gear cut corrects the distributor's shaft rotation for a REV RH rotation engine. Are you suggestin that both engines are Std LH rotation? That's not a smart ass question..... I actually don't know his set up. Perhaps his Stbd transmission does the rotational prop shaft change.
  2. Yep!
  3. Yep again.
  4. Ditto.
 
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1. Thinking here that the 454 CW and CCW engines spin the cam the same direction on the crusaders. So, the gear end on the distributor is the same for each type engine. Although for completeness, there are some non marine variants that have reverse cams as well, but nothing that i'm aware of in Crusader land.
 
The resistors do get very hot. They are designed to take the heat though. That's why ceramics are used in construction. Pretty sure the distributors rotate in the same direction. Spin the cam in same direction? I'm thinking not but would have to confirm. Normally the gears are cut differently (distributor and cam). Lushka, you should confirm if engines rotate oposite each other or if done at trannies....good to know for future refference.
 
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