I was trying to possibly "unclog" my secondary jets by placing my hand over the carb inlet opening and creating a vaccuum in which to suck the crud out. This was explained in a different thread. Well, I unclogged (too good) it and now whenever the fuel pump is on, gas drips out of the secondaries. When I turn the car off, the bowls empty out from the secondary jets. I took the front sight glass off and sprayed a bunch of carb cleaner in there thinking maybe I jammed the floats to the top. Seemed to be better but still doing it. I am gonna take the carb off and give it a good ol fashioned cleansing of the soul. Read: 5 cans carb cleaner, 1 nikki carb.

Ideas??? Just in case this doesnt work I mean.

 

this happened to me a few times on my many nikki's for me it was almost always the floats sticking.

 

The bowls cant empty from the secs. The fuel would have to run uphill to do that. Its your inlet valves on the carb. Pull the top, check the float levels, then remove them. Clean out the needles and seats, re assemble. Only other thing could be the vent solenoid isint working. Check that too.

 

Heres what I did. I changed to my other carb (also ordered rebuild kit). Runs ok, but needs some cleaning. Also didnt kill my "problem". I have a vid of it if anyone is interested in seeing it and giving some insight (carl, cough cough). From what I understand, it is the sound of detonation. My fuel pressure is dropping at WOT. It will go from 3 to 2 real quick, with or without secondaries opening(with or without mech secondaries). I am thinking that this is my problem, but I searched and couldnt find a decent answer. Everyone kept saying to upgrade fuel pump. I have already done this (sig). Also the weird detonation sound only happens AT OR AFTER 4K. ONLY then and never before. Do I need a better flowing fuel filter? Do I need a better regulator? The one I have seems to regulate ok (for lack of better words). I have tried a different filter but it didnt help any. Also I figured out that my return line was clogged, so that is fixed. Which would also explain why removing the silver thing inline on the return allowed my car to run correctly. Every time I do something I hope it will kill this damn sound. Could it be the fact that I am missing a stud on my header? I cant feel anything around there and spraying flammable stuff (carb cleaner) on that location doesnt do anything. Know that engine is cold when I tried this.

More about the 4K and different ideas:

Exhaust leak at manifold - Least likely I think, considering it happens after certain rpm.

Fuel flow issue - not sure how to fix that but would be nice.

Timing - I have read I think that 4K is where total advance is at. Meaning, the vacuum has done its thing and centrifugal has advanced as far as it can by this point.

Alternator - Its getting weak. Weak to where there is a drop when I use turn signals. Could it be that the alternator just isnt keeping up good and forcing less power to be going to my fuel pump? Lights do not dim. Just thinking of options here.


I have adjusted my timing a bit and have noticed that it will have serious cold starting problems if retarded and a little more hesitant on starting if advanced when hot.

This whole problem is seriously boggling me. I have done most mods to get rid of this problem (not SP and exhaust though obviously).

So, IF fixing the fuel pressure issue doesnt fix it, I am rebuilding carb. I will anyways just to make sure.


HELP
Ian

 

Sure, Ill help ya out. Email it to me.

Check your fuel delivery. Measure how long it takes for the pump to pump a gal of gas.
Also, you still run a return line and you have removed the silver restrictor? THATS a big problem right there. Your getting most of your fuel going right back into the tank instead of into the carb. If you have a regulator, you can deadhead the carb. Block the return and see if that helps.

 

Yeap, I was having constant trouble with fuel pressure with a 7 psi carter pump and a 0-4 psi Holley FPR until I blocked the return line. End of problems!

 

Sorry, my post was big so I didnt get into enough detail I guess. The deal with the silver restrictor thing was that my car ran just as it normaly did when I took it out because the line was clogged. So, in all reality the restrictor didnt do anything until a couple days ago when I checked it and figured out it was clogged.

The main noise problem has been found. I spoke with another member (cant remember screen name) and he thought it was the timing being 180 degrees off. That was exactly it. It still needs some tweaking but it runs MUCH MUCH better than before.

Also with the carb problem you nailed it on the head Carl. It was the needles and seats jst as you said. Cleaned em up and away I went. Also on a side note thanks for responding to all my idiotic and dumb questions about this and other questions I have had. it is appreciated.

Ian Smith

 

Cool glad you got it. Theres no dumb questions except the ones we dont ask.