86 supra , 1409 edlebrock carb issues

hey guys , i put a 1409 edlebrock on the supra cause the holley was giving me problems and was tired of messing with it , but now i have put a new 1409 600 cfm marine edlebrock on the 351w , in the driveway and on the hose it will run great at idle starts great and has no issues , i took the boat out to the lake today and ran fine on the water for a while , docked it and went to just start it and let it idle to charge the batteries and had to pump some gas in and took a while to finally turn over . took it out on the water and opened it of "WOT" and it popped and kind of slowed up like a lean pop almost . so then i shut it down to idle and it just idle out and died , took a while to get it back started and the proceeded back to the dock , got back and parked it , tried to star again same thing pumped gas and took a while to start , 4-5 times of cranking and pumping fuel .. so here is what i have "new" on the boat ,( plugs , marine wires , mallory elc ign, 1409 carb , accel coil w/o the ballast resistor ) on the coil i also noticed it gets real hot to the touch , it is internally resisted ..


i really really have lost my mind on this and i know its fuel related at some point but i cant narrow it down . and advice second thoughts would really appreciate it ..

happy holiday guys



lively

Have you checked when it is hard to start that you have spark? Never hurts to confirm, you said you know it's fuel related but didn't say you checked for spark. Just pull a plug wire and hold 1/8" or so from a good ground on the engine and crank, watch for a good hot white/blue spark. If no spark, that's your problem. If spark is weak (yellow color and sounds weak), it may be ignition related (or not). I had issues after switching to a Mallory Unilite with coils overheating after 20-30 mins and being hard to start or stalling for a period then working fine when they cooled.

Anywho, when it's hard to start pop the frame arrestor and check that fuel is not dripping down the venturis. Could be high float level and flooding after shutdown. Common problem exacerbated by heat. Helps to determine if we have a lean or rich condition making for hard start. If rich, pumping fuel into the intake will only make it worse when you should actually be holding it wide open while cranking (my Morse control prevents this and only lets me crack it in neutral, irritating). Also check for vacuum leaks, they can be intermittent and cause varying levels of trouble.

If your backfiring through the intake when accelerating, particularly quickly going WOT, you need to adjust your accelerator pump for a larger shot of fuel or a shot that starts earlier. Not sure how to do this on an AFB style carb as I have little experience tuning them. This is likely unrelated to your hard start problem

Is this just a hard start problem when hot or are there poor running issues at idle, accelerating lightly, or at sustained speed? I'd begin by checking your float level, idle mixture, vacuum leaks, and checking spark when it's hard to start. Never hurts to check timing too. Start with the basics.

It acts like it runs the bowls dry and then as I hold idle while in gear say around 2k it will take the WOT for short burst with no hesitation , but I did check coil v , on was 10.23 and cranking was about 8.40 witch is too low in my book thus not turning the engine over fast enough . I guess I need to by a Noid light and check and make sure it's not spark . And once I find a 1/8" fuel press gauge I'll put that on the input line for the carb .

Let me ask you this , what did the ballast resistor do for the stock coil ?


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And all this is when the boat is on the water and the engine is hot 170-200 degrees and the coil is hot to the touch , on the hose at the house it will idle , start , WOT , you name it . I let it sit for about 10 min running in the driveway and shut it off and just went to restart and started great and idled to 8-900 rpm like it should . Timing I did by ear this morning , but I have a gun and I'll check that . No fuel drips but I did catch it acting up on the water and took the spark arrester off and revved it up and it was stuttering with a lean pop , so I closed the choke flap alittle bit and the revved it up again and it was a clean rev without hesitation . So your right I need to verify spark , fuel pressure , timing .

What fuel pressure is a median to look for ?


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I noticed you have a new Mallory ignition. Do you mean the breakerless module? Some of the Mallory ignition modules require a ballast resistor. The older ones sold by Ski D.I.M. did for sure. The internal resistance of the coil does not resist the hot lead to the ignition module. With an internal resistor coil, the ignition module is still seeing 12 volts, off the positive side of the coil terminal, but it's only designed to take about 9 volts. That's trouble.

What the ballast resistor did for the stock coil, you asked, was to reduce the voltage to it and the points. Exactly why is beyond my confident knowledge, but I think it was to increase the life of the points. A full 12 volts would cook these coils sooner than later, since they were designed for 9 volts. Not quickly, but eventually. I think it's the same for your ignition module if it's not designed to be paired with a high voltage (internal resistance) coil. Keep in mind the voltage sounds low compare to the coil output, but 12 volts is 30% higher than 9 volts.

In other words, if the Mallory rig calls for a ballast resistor, you probably need to have one, period. You could get a different ignition module designed to be paired with the internal resistor coil. Cheaper to put the ballast resistor back in, and get a standard coil - most likely.

At any rate, with my motorcycle, I paid for a carb rebuild when it turned out to be ignition troubles. I was 100% convinced it was the carbs. They can fool a person, that's for sure. But, as history shows, I'll continue to be wrong quite often.

http://img.tapatalk.com/d/14/05/27/u8yry9y5.jpghttp://img.tapatalk.com/d/14/05/27/u3anuvab.jpghttp://img.tapatalk.com/d/14/05/27/uqa6arar.jpg. I have looked for part number on the dizzy and can only see YL56 something , the coil is accel 8140 and I have a fuel pressure port that I just need the gauge but I gotta find one local hopefully . Do you think I need to go back to ballast resistor and stock coil ? What coil part number ? Can I get that at the oriellys or autozone ?


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http://youtu.be/m3dNXcvjXyg


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http://youtu.be/smFJNOsQ0jA


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From what I can tell, the "YL" series Mallory distributors are set up to run modern "high voltage" coils. (internal resistor, no ballast) Now, big disclaimer here, because I'm more familiar with the Prestolite distributors. So, I'd maybe still see what you can find out about your distributor to set your mind at ease, but it seems like you should be good from the ignition point of view. Mallory makes/made the breakerless module that you drop into an O.E.M. distributor, and that's what I was basing my prior stuff on.
I think your set-up is fine.

I just know that ever since I put this on the engine and deleted the ballast resistor it's never ran the same . It's been a year or so since I've messed with it . So I'm thinking that I'll just go back to the stock setup and try that . I really truly believe that coil is not supposed to be that hot and it's throwing red flags at me . Now I gotta remember how the resistor is wired for the coil .


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The resistor should go into the wire route that leads to the positive side of the coil. There is probably a splice where you removed it from the path, at the back of the engine, off the ignition solenoid, (by big red button circuit breaker) just a couple connectors and you'll be back in business. I think the Mallory YL distributors are fine with any configuration, but at this point you probably want to get rid of some variables. Any small block Ford coil is fine. I think I have a basic NAPA on mine, but am not near boat so sorry I can't tell you model number. Though, right on the coil it says "must use with ballast resistor". Good luck. I know in your video the subject of a hot coil got mentioned again.

I found out that the coil I have is a 1.5 ohm and 8140 needs 1.5 of resistance to bring down to 8.0 v during run , 12v start and then the ballast should bring it down and with 13.6 average return voltage I think should be the reason my coil is getting hot . I went up to autozone and ordered a ballast resistor and I'm going to wire it like Mallory instructs . If the coil still gets hot I'll change it with a napa one . Thanks for the info and I'll post back when I get it buttoned up


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http://youtu.be/mno2TBwgkTM


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http://youtu.be/7LyJtyJPSEM


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Anybody know the ohm reading of the standard coil that came on the 351 ? I've narrowed it down to the wrong coil I believe and I need some help on this


Or does any one have OEM numbers off there's ?

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Well I found my old coil in the tool box but no labels . I'm gonna put it back on and try that tomorrow


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The symptoms sound like low fuel flow to me. Ignition will backfire through the exhaust. Popping through the intake is an indication of a lean condition (or sticking valves...which is not likely).

I would check fuel filter and then the fuel pump. Is it mechanical or electric?

Mechanical . I have 6 psi at fuel line , I have two Inline filters one before pump and one after . They are both new as well as the line . Now I do see the fuel pressure go down when engine begins to stall witch it would because the pump is mechanical . I might try a electric fuel pump and see if I can get it to change


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6 psi is good. You should have the 6 psi as long as the engine is turning at all. In fact, it should remain close to that even after the engine stalls, as the check valves in the pump should not release the pressure, and the carb isn't using any fuel then...unless you are pumping the throttle...

Is there a chance it is vapour locking? One time, also in May here in Texas, I could not trace a poor run/stall condition. I finally used clear fuel hose and actually watched bubbles form and expand out of nowhere in the hose. I finally deduced that it was unseasonably hot and the fuel mix I had was blended for winter temps. A fuel change and I was good. The wild thing is that you still see good pressure with a vapour lck, but it's reading vapour pressure instead of fuel pressure.

There's 93 pump gas in there and some octane booster lol . I am going to look for a good 6-7 psi electric fuel pump and then see if anything changes , but first the old coil is going back on to see if that changed anything , problem is the fuel pressure regulates when the engine stalls or sputters , and the carb wants to see 6.6 psi no more no less . So I'm gonna do both and see what happens lol !


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I contacted edelbrock at lunch and they said for the 1409 that 3psi @ WOT is the minimum and 6.6psi is the maximum .

I've always had 5-6 psi @ WOT and never seen it drop below 4.5psi . So this has got me wondering . Brand new carb


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Got the ballast wired as it was when I got the boat , and how Mallory states 12v+ at coil positive , spark is a lot better but coil is still hot . Like 185 degrees to be exact and the ballast is not hot at all . I thought I should be seeing a voltage drop ? Am I ?


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I found a wiring diagram online finally ! So I'll check it out this weekend on the water hopefully that fixed it


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http://youtu.be/9-N2OgZGpzo


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That's awesome Lively. Sorry for your troubles, but your diagnosis and videos will certainly help others who need to work through similar issues. I rebuilt my engine this past winter and thought about removing the ballast resistor when I rewired it all, but then discovered that some Mallory electronic distributors still required the resistor. So I left mine as well.

Glad you've got it running right. It really sounds good.

Thanks Titan ! Sometimes I over look things and should have looked at the elec print and wired it up that way . Tomorrow I'll know if my findings were correct . And I changed my prop out last night after hitting stump and ripping my new one up http://img.tapatalk.com/d/14/06/01/qahuhy3a.jpg


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Ouch. I recently had a similar issue when my prop shaft slipped out of the tranny and the prop hit the rudder. It's being repaired now.


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i took a old one i had that had some dings and chips and put it on a belt sander and smoothed it out and leveled .. no vibration at all .. boat ran great today but im thinking its time to upgrade to a electric fuel pump .. i ran the engine for 4 hours non stop and at the end of the day it felt like it was missing and the idle was at 5-6 so i adjusted it to 999 rpm and cleaned up .. but i later noticed that fuel pressure was not at the rail during restart and had to crank the engine over 4-5 times to build it back up and fire it .. once it started it ran fune and fuel pressure held at 6.5psi .. but this guy is happy the boat runs !!!

Hey sorry, meant to follow a bit sooner but got distracted. Glad you found the O.E.M. diagram. And very glad you got it sorted out.

Just to confuse things, did you ever run across this Mallory diagram?

http://prestoliteperformance.com/med...7_38_45_47.pdf

I imagine it's figure #1 that you have going.

Best,

Grover.

That's how I wired it first ,and it didn't don't anything different just had a weak spark and voltage never dropped , but PCM wiring diagram shows dizzy wired to pos + of coil and then coil to ballast , choke on 12v side coming in with S term to ballast .


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I know; the Mallory diagram doesn't make sense to me, especially that "all other wires" part that are connected to the (+) of the coil. In our case, that could be seen as the electric choke, and that wouldn't have been right since it would have only gotten 9 volts.

I am probably going to replace my old Mallory ignition module (ten years ago model) with a newer model, but it is still designed to be used with a ballast resistor. I notice on the PCM diagram, it shows a "bypass" for Ei (which I guess is Electronic ignition) on the resistor, but that's not always going to be a good idea - like in your and my case.
We need the resistor.

In any case, glad you worked it out.