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engine is flooding


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I have a L16 in my 521 and the guy I bought it from put a 2 barrel holly carb on it. Problem is there is no place on the carb for a choke. So as you might think it doesn't like to start when its cold, and it ends up flooding even when I don' pump the pedal for some extra gas before I crank it over. Another interesting thing about it is that there was a newer style 1974 plus distributor on it which was really difficult to find condenser/cap/rotor for so I swapped out that for an older distributor and Its pretty much impossible to start when it is cold (had to tow start it last time).


So basically I was wondering if anyone had any ideas on what I could do to prevent it from flooding so easily and where I might get parts for the older distrib. and or a link to a match box dizzy conversion. Opinions would be much appreciated.


Thank you



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Make sure the carb is adjusted correctly. Dizzy shouldn't matter tooo much, make sure the points are gapped correctly.


You can run a 78 or newer matchbox distributor and eliminate the points, much better system. Make sure you get the coil from an electronic dizzy (matchbox distributor) if you do the swap.

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It must have a choke on it. It's the thing at the very top that closes when cold.


here's one with the chike on



...and off.






Very unlikely to flood when cold if the choke isn't working. If anything it's working too well!!! and flooding.

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It's a Holly, look in the junk yards for the parts for it. Some are electric and shut off by themselves. Sounds like yours is on all the time. See about a manual cable so you can set it on and tuen off by hand.


Distributor: http://community.ratsun.net/topic/28652-ei-dizzy-on-rockauto/

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the early l16 dizzy pedastal the tang might be different than a 74 dist. YOU got to be certain unless you swap the whole dizzy with the pedastal.

Timming will help it start better. if its with in reason.


is this a stock set up? with the stock coil and ballast resisitor? I say the 74 dis is better is its a single point. the dual point dizzy only uses the 1st points any way till it hits 3rd gear( it switches in).


I dont use a choke on my weber DGVs. i just pump the pedal to enrich the carb circut. if motor floods right away it could be the float is off letting to much gas in.

or your not getting good spark In the START position.



this is a EZ fix.

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It is close to being timed properly, it's a single point dizzy from an l16 so it should be stock. What would be the fix if the float is messed up? Open it up and clean? Also the dizzy may not be a huge problem as I have a 200sx NAPZ20E with EI dizzy on it that I am looking to use just need to find a coherent thread to read up on.

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If you have a orginal single point L16 dizzy you can but a Pertronix in there. about 75 dollars


If your motor is timed good then lets work on the flooding issue first.

Holley carbs might have a external float adjustment.



If you want to go EI ignition make sure to use the EI coil and then you can remove the point coil and ballast resisitor. TYou can use them if you like but you wire it up slightly different but you dont get the full 12volt spark.



My 2nd 510 which i still own it would be hard to start also. the timming chain and tensioner were so worn.

also ck to make sure intake manifold and carb bolts are tight.


you could try if its hard to start and you think it flooding,pull the plugs and put new ones in. and start it with out hitting the car. if still dont start you got to ck the timming again.

mayeb the idle mixture is off. I just dont know Holleys

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For now forget the dizzy. Put it on when you get the fuel sorted out. If it IS flooding or over choked the plugs can misfire and make you think it's the ignition. Pull the plugs... if covered in black sooty powder or black and wet then it's running rich. An EI dizzy won't fix this.

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Just put the plugs in last weekend so maybe too early to tell by looking at plugs my Dad is thinking he just had the carb over adjusted so he leaned it out a lot, we also charged the battery overnight just to make sure it wasn't weak. We have the timing adjusted to about 12 deg, but with the non stock carb and distributor that are currently in it I'm not so sure that is the correct timing.

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A weak battery will affect cranking but once started should be in the 14 volt range. Even at 10-12 volts there's enough to fire the coil.


Plugs will get dirty very quick so pull them and look. This is probably the best tool for seeing exactly what is going on in the combustion chamber.



Did you set the timing with a light? Or guess?

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Plugs have a block sooty/slightly wet ring on the end of the thread but the point where spark is generated is brown and clean in appearance. After the carb was leaned out it starts up but wont idle unless i give it a bit of gas for a min or so, which makes me think its just really cold blooded but idk.

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When I had to tow it to get to to start eventually, I would crank it over and I think battery was a bit weak so it wasnt cranking over properly it would sputter a sec and then die, giving it more gas killed it instantly where if i let it be it would sputter for 5 sec and die. So i let it sit and it did the same thing again. So we towed it to get it running well enough to idle adjusted down the carb. It was still doing the sputter thing till we eventually messed with the carb for a few days (leaned it out almost as far as the adjusters would turn) Then it had and still has a really shitty idle and barely runs until i let it sputter for 5-10 min like it needs to warm up. When it does finally warm up and gets slightly better idle it has a hesitation and we have been trying to adjust and mess around with the carb to lessen that hesitation.


The hesitation is from idle almost like it wants to stall out when easing on the gas.Been constantly messing with the carb and have adjusted the timing a few times to make sure it was right. It's not easy for me to really explain any better trying to get an opinion from my dad is like trying to steal a banana from a monkey so I am just telling ya what Ive seen/helped with. The car had some mechanical problems when I bought it and we keep finding more maybe something there is something we haven't found yet that is causing this.

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We did adjust the valves to .08 for intake and .010 for exhaust (8 thousandths/10thousandths) which I believe is what olddatsun said, the clearances were really jacked up before we adjusted, .012 on some intake .08 on some exhaust and for they most part they were all backwards from what it is supposed to be. And yes the carb pushes a strong jet of fuel into the bowl when I pump the gas.

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