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itselliott

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I SHOULD know this , but alas age has me looking thru cobwebs.

Having just rebuilt my smallblocks , it's time to reinstall them. 1st, I have been running without ballast resistors and a Mallory electronic distributor for nearly 15 years. While wrenching, I somehow noticed that I have 9V coils in there, and have had them in there forever. Again without the ballast resistor.

Here's what I am wondering...........
Should I install a 12V (HEI) coil like, say, from a Ford ignition. Or put the ballast in line with the "run" side? Seems to me that the engines have been running as is for a LONG time but I fish (Troll) at idle almost 90% of the time. I have to think that with the Mallory distributor, I SHOULD have a 12V coil............???????

BTW, we are talking 1986 350, carburated, Crusaders .
 
Depends on which Mallory system you have.... YLM or YLU.
But in general, Mallory allows for either resisted or non-resisted voltage for the sensor unit, as you can see here.
Dist-Wiring-Diagram.jpg


The ignition coil will determine the coil voltage.
It will either require the ballast resistor, or the coil may be internally resisted.
Follow this, and you can't go wrong.

Mallory does make a suggestion for a coil to be used with their systems. Perhaps use Mallory's suggestion.


Make sure that these older Mallory's are giving the correct progressive advance curve and limit. It's never a bad idea to have them tested by a shop who owns an old school distributor machine.
If the curve needs to be adjusted, they can do this... but make darn certain that they use the correct Marine specs.

Also, make sure that if you went back together with the full dished pistons, that you are conservative with your TA when timing your new engines.
The full dished pistons will not allow for quite as much TA as will a build using a quench style piston.

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I'd say if you have 15 years on them they are highly likely to be internal resistor coils. If you are doing a rebuild, it makes a lot of sense to replace the coil and put the old one in the spare parts locker. I'd be inclined to use the same coils given their performance.

Also concur with ensuring the advance mechanism in the distributor is A-o-k...those springs are the only shortcomings of those distributors (& Mallory isn't the only one here).
 
iselliott said:
I SHOULD know this , but alas age has me looking thru cobwebs.

Having just rebuilt my smallblocks , it's time to reinstall them. 1st, I have been running without ballast resistors and a Mallory electronic distributor for nearly 15 years. While wrenching, I somehow noticed that I have 9V coils in there, and have had them in there forever. Again without the ballast resistor.

Here's what I am wondering...........
Should I install a 12V (HEI) coil like, say, from a Ford ignition. Or put the ballast in line with the "run" side? Seems to me that the engines have been running as is for a LONG time but I fish (Troll) at idle almost 90% of the time. I have to think that with the Mallory distributor, I SHOULD have a 12V coil............???????

BTW, we are talking 1986 350, carburated, Crusaders .
Click to expand...

OK, Let me try to clarify this...
The code on the distributor is YH.
There are only 2 wires connected to each distributor (always have been)
The coils state"use with external resistor"..........Here's the rub, there have never been any resistors.
I DO see a spot on the coil bracket that could have been a mounting spot for a resistor.

I purchased the boat as the 5th owner back in '99 and have owned it since.
I have put 2000 hours on the motors(thus the rebuild) they had 750 when I bought it. So, 2750 at the time I pulled them.
What I am trying to figure out is the "BEST" way to configure the ignition/coil.............Also I am not understanding how this set up has functioned with a resistor required coil and no resistor in the system?????
 
Iselliott, if your coils state "use ballast resistor" then it's possible that your coil power leads are resistance wires.
Check the voltage to the + side of the coil with the triggering wire disconnected.

In the Marine distributors by Mallory (for the SBC) you'll see the YL, YLM and YLU in the 624 AV or AB series.
I am not aware of a YH for the SBC Marine. The only thing that I find on a YH refers to an advancing system for a VW car.
Can you post photos of it for us?

Two wires suggests to me that the Pertronix kits may have been added to a YL 624 mechanical type ignition distributor.
This would be a black and red wire, and these would be the Pertronix Hall Effect units.... not the best for performance, IMO.
If that's the case, you may want to replace these with a pair of Mallory YLM 624's.... in the AV and BV version.
The AV and BV gets you the correct distributor for the Standard LH rotation and the Reverse RH rotation engine.

NOTE: the RH Reverse rotation engine places a downward force on the distributor shaft, so the housing/shaft must accommodate this downward thrust.

Or, if you don't mind EST, Mallory offers the YLE624AV & BV non-HEI, and Delco makes a decent EST system in non-HEI and HEI.


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I'd be a bit cautious about the BV distributors, as these are Crusader units - they have NEVER used a reverse rotation engine.

I don't see anything about a YH being available in a marine unit in the little bit of literature I have. that said, mallory has had a few owners over the years and anything is possible.

Bottom line is the distributors will work with most coils; it is the coil that determines the need for a resistor and the resistor is the normal ceramic packaged retangular unit or can be implemented with resistance wire (not a crusader feature either). I'd suggest getting all the info off of the distributor ID plate and calling mallory's tech support line (or send an email). they will tell you what is the 'best' way to configure your ignition. Just make sure to remind them it is a marine application.
 
makomark said:
1.... I'd be a bit cautious about the BV distributors, as these are Crusader units - they have NEVER used a reverse rotation engine.

2... I don't see anything about a YH being available in a marine unit in the little bit of literature I have. that said, mallory has had a few owners over the years and anything is possible.

3.... Bottom line is the distributors will work with most coils; it is the coil that determines the need for a resistor and the resistor is the normal ceramic packaged retangular unit or can be implemented with resistance wire (not a crusader feature either).
Click to expand...

1.... Ah, the reversing transmissions! I hadn't considered that. Good point!


2... Well, that's what I came up with also, Mark.


3.... Agreed!

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Guess my proof reading is suffering a bit...should have said Crusader has never used a reverse ROTATION distributor in their reverse rotation engines....i.e.; you can take a RH & and LH engine from Crusader and you can swap the distributors between them w/o issue.

The little I did find on a YH is that this designator appears to be older and denotes an advance mechanism used...
 
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makomark said:
1..... Guess my proof reading is suffering a bit...should have said Crusader has never used a reverse ROTATION distributor in their reverse rotation engines....i.e.; you can take a RH & and LH engine from Crusader and you can swap the distributors between them w/o issue.

2.... The little I did find on a YH is that this designator appears to be older and denotes an advance mechanism used...
Click to expand...

1..... I'm, not aware of any Marine RH SBC that has used a reverse rotation distibutor.
If we rotate the camshaft in reverse along with the crankshaft....., the helical gear cut of the BV allows the distributor and oil pump to rotate standard. This is also what causes the downward thrust on the distributor shaft.
If you double gear drive the RH SBC special camshaft, then this is a non-issue.
Is that what they're doing Mark???


2.... Same here, Mark.... something about a VW engine, but I did not read any further.


iselliott said:
This looks like it might be what I have..........

I'd like to get the proper set up. It looks like it had resistors at one time. there is a wire cut off(closely) at the coil where 2 purple wires were affixed into a single connector (molded)
Click to expand...


Personally, I'd not waist my hard earned money on one of these units. Your fresh engines deserve a better and more accurate igntion system.



As for resistors -vs- no resistors, again, let your coils determine whether or not these need to be externally resisted.
There's no sense in adding external resistance to thses circuits if the coils are internally resisted, and/or visa-versa.


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Again, I have not changed anything since I purchase the boat in 99.
The situation is only to get it right, now that the motors are rebuilt. Another Grand($$$) at this time isn't in the cards.

I have what I have........but ...........I do not know if it correctly done.

The whole resistor or not thing is the "concern" I have.

Do I fry the current didtributors ...."IF" I install an HEI 12V coil??

Why ??? do my current coils say "resistor required" and yet there are no resistors??? IF this is WRONG, then WHY?? are the coils not cooked ??

That, gentlemen, is the delima.........

If $$$ were available in large quantities, I would like new HEI distributors......but alas, I am in perpetual pauperdom.
 
At bare minimum, I'd have your existing 26 year old 1986 distributors tested for the curve and limit.... and make darn sure that it is correct for Marine.
The last thing that you'll want to have occur, would be ignition induced detonation damage to your fresh engines, and in particular if you went back together with the full dished pistons.
I've seen first hand the damage that can result.

2 or 3 degrees out at the distributor, is 4 or 6 degrees at the crankshaft.

Kghost, if you read this, I know that you hate to hear this repeated, but I think that it's important to mention.


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iselliot:

To figure out what you need to "make it right" you have to know what's inside.

Seriously, if you have several years on any given configuration, it is likely to be ok. The need for the resistor is driven by the coil and the triggering mechanism and is a function of the current flowing thru the circuit; too much = burnt components, too little and your spark suffers.

If you want to make sure things are balanced, verify the trigger brand installed, get their install sheet, and get their matching coil (& resistor, if needed) and you should be golden.

The stamp on the coil saying "resistor required" was applied assuming a certain ignition configuration. The coil maker applied it using their 'best judgement" with a certain amount of guess work on how it will be used...if it really needed a resistor, I'd doubt you would have seen more than several hours of use before the "smoke got out" of the case.

Rick: what I was getting at is that I haven't seen a RH SBC in factory configuration that used anything but a LH distributor; ie the '624AV type vs the BV type. The crank spins 'backwards' and a 2 gear drive spins the cam 'normal', thus the need for the A (LH or Normal) gear on the distributor.
 
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