V8_DatZun Posted February 11, 2007 Share Posted February 11, 2007 well... i got everything together to finally break in my 383 stroker. my dad and i tried to fire it up a couple of times nothing... then it finally fired... spit and sputtered pretty bad.. believe it got flooded the Fuel pressure reg. wasnt set right... so i spun it over and dried it out till it sounded like it wanted to fire again.. got it to fire up and run.. it has a popping noise like and blowing dark black smoke out... smells like gas so we cut it off.. tried to fire it up again and it spun freely... was getting fire to the HEI but nothing... changed the ign. module and then it fired up again.. the spark is a dull red color though... when we arc the spark plug wire to the frame.. is it possible the coil pack is going bad instead of the ignition module... or maybe both were bad? it runs but it sounds pretty bad... maybe timing is off too.. cant leave it running long enough to set it. any suggestions?? Quote Link to comment Share on other sites More sharing options...
Teekass Posted February 11, 2007 Share Posted February 11, 2007 well... i got everything together to finally break in my 383 stroker. my dad and i tried to fire it up a couple of times nothing... then it finally fired... spit and sputtered pretty bad.. believe it got flooded the Fuel pressure reg. wasnt set right... so i spun it over and dried it out till it sounded like it wanted to fire again.. got it to fire up and run.. it has a popping noise like and blowing dark black smoke out... smells like gas so we cut it off.. tried to fire it up again and it spun freely... was getting fire to the HEI but nothing... changed the ign. module and then it fired up again.. the spark is a dull red color though... when we arc the spark plug wire to the frame.. is it possible the coil pack is going bad instead of the ignition module... or maybe both were bad? it runs but it sounds pretty bad... maybe timing is off too.. cant leave it running long enough to set it. any suggestions?? Just a guess, but it sounds like it may be running too rich? You have a new Holley Double Pumper on there, right? First thing I would do is double check the fuel pressure....should be between 4 and 7 psi. Too high of a pressure could overpower the float, and cause fuel to end up dumping directly into the intake (through the boosters).....could be the fuel that you're smelling. Next thing, take the handle end of a screwdriver (or the like), and tap the float set screw on the end of the bowls (both the front and rear). I know this sounds crazy, but the new float may be sticking open, or there may be a piece of debris holding it open. Tap it in an attempt to free up the float, so that it can shut off the fuel going into it. After tapping both of them a dozen times or so, try to start the engine again while tapping them some more. If that doesn't work, check the float levels....they may be set too high. Are you familiar with checking and setting the float levels? If that doesn't work, put another carb on the engine that you know runs well. Quote Link to comment Share on other sites More sharing options...
datsunlover Posted February 11, 2007 Share Posted February 11, 2007 I've seen coil packs go bad a few times, even when they're fairly new.. I'd replace that for starters.. and if you're just holding the spark plug wire boot on the engine, you wont see much of a spark. Get an old plug and stick it in, then ground the plug to the motor to see if it has a good spark. (Do NOT hold onto it my hand thought! that hurts...) As for the black smoke, the timing is probly running too retarded.. This might sound silly, but check and re check that the firing order is correct.. IE; the plug wires are all in the right spot! I fought with a motor for 20 mins once before I realized the guy I got it from had the plug wire locations BACKWARDS. It would almost run, but kept poping out the exhast/carb and blowing black smoke. Quote Link to comment Share on other sites More sharing options...
Guest Mike Posted February 11, 2007 Share Posted February 11, 2007 As stated above... the floats still stick on the Hollies sometimes. This has been an issue for... forever. Why won't they fix it? Quote Link to comment Share on other sites More sharing options...
V8_DatZun Posted February 11, 2007 Author Share Posted February 11, 2007 no im not sure on how to check and set the levels... i tried to get on holleys website but their PDF froze up my computer... it ran fine a week ago.. well ran fine for like 30 secs at a time.. i had to dump the oil from it flooding from the Fuel pump being wired strait to the ign on switch. changed plugs.. put in an omni oil press switch.. it DID flood a little cuz i had to spin it over a while.. THEN it acted like it wanted to fire up.. then connected the fuel pump back up.. it started up but spit and sputtered.. it ran for a while like that... and i plugged the back intake hole like you suggested.. do i need to unhook the vacuum from the distributor till i get everything set? also i guess i need to unhook the vacuum from my fuel pressure regulator.. hell.. guess ill unhook the brake booster too.. plug the carb holes up.. start it... and hook one thing up at a time... thanks for the help though man... ill let you know what i find out tomorrow. and datsunlover.. ill check the wires again tomorrow... i DID have to unhook them the other day.. maybe i got 2 swapped.. thanks again for the help.. ill post info tomorrow. Quote Link to comment Share on other sites More sharing options...
Teekass Posted February 11, 2007 Share Posted February 11, 2007 Heres an idea that will tell you if its a float problem.... Pressurize the fuel system, for 30 seconds or so (long enough to fill the bowls with fuel)......while you're doing that, look down the throat of the carb. and make sure fuel isn't dripping from the boosters. Then disconnect the fuel pump, and try to start the engine WITHOUT the fuel pump ever coming on (do whatever it takes to make sure the fuel pump never comes on). If the engine runs fine for 20 seconds or so, then quits (because the primary bowl ran out of fuel), then it most likely is a float level, stuck float, or fuel pressure problem. Quote Link to comment Share on other sites More sharing options...
mamba_888 Posted February 11, 2007 Share Posted February 11, 2007 ...First thing I would do is double check the fuel pressure....should be between 4 and 7 psi. Too high of a pressure could overpower the float, and cause fuel to end up dumping directly into the intake (through the boosters).....could be the fuel that you're smelling. I have a manual on tuning Holley 4150/4150 carbs and according to it, the float level will rise if one opens the gas intake port or raise the fuel pressure. For every 1psi raised, the float will be raised 1/32 of an inch. This is an old manual but is very comprehensive. It describes everything as I show below: - Intake system - Idle system - Main jet - accelerator system - power system - secondary system (vacuum and mechanical) - choke system Let me know if you need me to look up something for you. Hope this helps. Quote Link to comment Share on other sites More sharing options...
Teekass Posted February 11, 2007 Share Posted February 11, 2007 Before you do what I wrote below, try what I posted above about removing the fuel pump and pressure from the equation. It's quick, and will tell you if the problem is in the fuel system. If the engine ran fine for a bit, then quit, try checking the float levels: To check the float levels, use a flathead screwdriver and remove the screws (one per bowl) from the side of the bowls (passenger side). With the engine running, the fuel should be right below the bottom of the hole where the screw fits....you should have to shake the car to get fuel to seep from the hole. Since you can't keep the engine running long enough to set the levels, you'll have to do this a little differently. Turn on the fuel pump, and see where the fuel level is. If it's running out of the hole, the level is too high. If there is no fuel coming from the hole, but when you bump the fender, fuel does runs out of the hole, then its just right. If you bump the fender, and no fuel seeps out of the hole, the level is too low. (I'm hoping it's too high, and the root of your problem). If it's too high (this is going to be a little messy)...Use a big flat bladed screwdriver to loosen the set screw on the end of the bowl (its on top of the bowl, right above where the fuel line comes in, and it sits on top of a hex nut). Then use a 5/8" (I think) wrench and screw the hex nut clockwise until the fuel stops running out of the hole. Re-tighten the set screw using the flathead screwdriver. If it's too low, do the same but turn the hex nut counter clockwise until fuel seeps out of the hole, then turn a tad clockwise until it stops seeping out. And obviously, put the bowl screws back in when you are done setting the levels. Good Luck! Quote Link to comment Share on other sites More sharing options...
Teekass Posted February 11, 2007 Share Posted February 11, 2007 For every 1psi raised, the float will be raised 1/32 of an inch. Thanks alot, I didn't know that. As the fuel pressure raises one psi, the fuel level in the bowl raises 1/32 of an inch, but I know it reaches a point where it can't control the fuel level. The only strength the float has to shut off the inflow of fuel is the bouyancy of the float itself. As the fuel pressure increases, there comes a time when the pressure of the fuel coming into the bowl is too great for the float to close the valve (or said more accurately...it cant push the needle into the seat hard enough to stop the inflow of fuel). When this happens, the bowl gets pressurized and basically the fuel pump pushes fuel through the bowl, jets and straight out of the boosters. Thats what I was trying to rule out when I recommended he double check the fuel pressure. Sounds like a good manual you have there......what is it called? I'm always up for buying good manuals. Quote Link to comment Share on other sites More sharing options...
Guest rat454 Posted February 11, 2007 Share Posted February 11, 2007 I was looking over your other posts....Sounds like this will be a nice toy.... A few things As Teekass indicates be sure to get the fuel level correct. it's not so important that it is set exactly even with the fuel window sight plug so much as it is important that the floats are shutting off the fuel at the required level. Good call on changing out the oil. If you are running a standard flange carb on a performer intake, you may have a vacuum leak between the carb and the intake. Most performer applications require the use of a plate between the carb and the intake as they are designed for a spread bore carb....(I inquired on your other post about what type holly you are running) Also you indicated your spark was red...How much voltage do you have at the HEI with the key on? you should have at least 12 volts...if not try running a hot wire straight from the battery to the Bat conncetor on the HEI. use at least 12 gauge wire and a toggle switch rated at least to 20 amps as the HEI required alot of amps to run correctly.. Disconnecting and plugging all the vacum lines is a good idea...(I did a 455 buick swap into a regal and had problems, turned out the vacuum booster for the power brakes was bad...) Any way if you can get things down to the basic requirements for it to run then you can re connect things and see how they effect the engine... What's your plug gap at? Lastly (and it may seem like a Daa) but double check your spark plug wires against the firing order..I've gone daa on that one more than a few times... What all did you do to the 383.... Good luck and keep posting G Quote Link to comment Share on other sites More sharing options...
mamba_888 Posted February 11, 2007 Share Posted February 11, 2007 Thanks alot, I didn't know that. As the fuel pressure raises one psi, the fuel level in the bowl raises 1/32 of an inch, but I know it reaches a point where it can't control the fuel level. The only strength the float has to shut off the inflow of fuel is the bouyancy of the float itself. As the fuel pressure increases, there comes a time when the pressure of the fuel coming into the bowl is too great for the float to close the valve (or said more accurately...it cant push the needle into the seat hard enough to stop the inflow of fuel). When this happens, the bowl gets pressurized and basically the fuel pump pushes fuel through the bowl, jets and straight out of the boosters. Thats what I was trying to rule out when I recommended he double check the fuel pressure. Sounds like a good manual you have there......what is it called? I'm always up for buying good manuals. Thanx for the explanation about the float being overrun! Makes a lot of sense to me. I guess both our recommendations make sense here. The book is called (not exact) Holley 4150/4160, Tuning and Repair. It's a red book and if you do eBay Search on "4150 Holley", I see 2 of them being sold right now. Definitely goes into every system in the carb. I am building a 383 stroker for my 240z which will eventually be a twin turbo blow through. That is why I have the manual. Cheers. Quote Link to comment Share on other sites More sharing options...
Guest rat454 Posted February 11, 2007 Share Posted February 11, 2007 another thought occured to me...you could also have a bad power valve in the carb...if it back fired through the carb, and it ruptured the disc on the power valve (valves) then youll have idle problems and will run rich as hell... G Quote Link to comment Share on other sites More sharing options...
V8_DatZun Posted February 12, 2007 Author Share Posted February 12, 2007 it did backfire once, and blew gas out the top of the carb across my shop... ANOTHER thing that could be wrong that is kinda.. daa is that my battery is dead and im trying to jump the engine off... not a good idea and im going to get the battery fully charged today. i checked plug wires... correct order. the engine specs are as follows stock chevy heads w/over sized valves 2.02 intake 1.8 exh comp cam cant remember exact specs but its around .510 lift 2600 stall converter keith black hyper pistons holley dp 750 carb edelbrock performer intake lol its getting aggravating... cant get the thing running long enough to break in... Quote Link to comment Share on other sites More sharing options...
Paz8 Posted February 13, 2007 Share Posted February 13, 2007 This may sound alittle dumb but, do you have a GROUND strap from the engine to the chassis and is it making a good connection ? Quote Link to comment Share on other sites More sharing options...
V8_DatZun Posted February 13, 2007 Author Share Posted February 13, 2007 as a matter of fact no... lol i have a ground to my tranny/engine bolt that goes to my fenderwell near the battery.. would it really make that much of a difference? i didnt know. forgot about it in the rush to get the car running. Quote Link to comment Share on other sites More sharing options...
Teekass Posted February 14, 2007 Share Posted February 14, 2007 it did backfire once, and blew gas out the top of the carb across my shop.. Backfire through the carb (when setting the timing for the first time) is sometimes an indication of too much timing advance. Try rotating the distributor clockwise about 1/2 the distance between 2 plug wires on top of the distributor (or more if needed).....If you do this while trying to start the engine, the vacuum advance hookup part makes a great shock-free handle. Quote Link to comment Share on other sites More sharing options...
V8_DatZun Posted February 15, 2007 Author Share Posted February 15, 2007 i didnt check the fuel level yet.. i fired it up today it acts like its not getting enough gas... but i move the fuel pressure reg. screw it acts like the fuel pressure isnt moving.. (hard to tell by myself) but it STINKS of flooded fuel... smokes pretty bad too and if i dont keep on the throttle a little it wants to die. so its weird lol.. maybe a float IS stuck and just dumping fuel... that could be why im not getting a PSI reading for the fuel also?? im going to check the levels per your info tomorrow.. thanks for the help. Quote Link to comment Share on other sites More sharing options...
mamba_888 Posted February 16, 2007 Share Posted February 16, 2007 i didnt check the fuel level yet.. i fired it up today it acts like its not getting enough gas... but i move the fuel pressure reg. screw it acts like the fuel pressure isnt moving.. (hard to tell by myself) but it STINKS of flooded fuel... smokes pretty bad too and if i dont keep on the throttle a little it wants to die. so its weird lol.. maybe a float IS stuck and just dumping fuel... that could be why im not getting a PSI reading for the fuel also?? im going to check the levels per your info tomorrow.. thanks for the help. Don't know how old your carb is but there are brass floats (older style) and there are rubber floats. The brass floats leak in time! Anyway, I suspect that one way or the other, the float is the target here. Either, it is being overrun, it's leaking or maybe the pivot/spring is stuck. Carb rebuild maybe???? Hope this helps. Also, please keep us posted even after you slay this gremlin. Good Luck!!! Quote Link to comment Share on other sites More sharing options...
V8_DatZun Posted February 17, 2007 Author Share Posted February 17, 2007 the carb was a reman. one from a ebay dealer in AZ that sells rebuilt carbs. they are said to have been tested (i bought this a YEAR ago so i HOPE not being on an engine in a year hasnt dried it up inside) and if they aren't running right then you arent doing something right is their claim. im tempted to just buy an edelbrock and throw on it... i've had so many people tell me holley's are REALLY picky carbs.. better carbs.. just REALLY picky.. i still have to check the float levels like what was suggested i've been pretty busy lately.. once i do that i'll post my findings.. thanks for helping out on this problem guys. Quote Link to comment Share on other sites More sharing options...
Michael Posted February 17, 2007 Share Posted February 17, 2007 If a float is stuck at the pivot, then there will be a fountain of fuel gushing out of the corresponding bowl's air breather tube. This happened to me after I removed one of the bowls to replace a sight plug. My Holley sat for 5 years while the engine was being rebuilt. Over those 5 years, the only discernable damage was rotting of the rubber O-rings in the needle/seat assemblies. You might want to check those. Other than that, is is unlikely that age alone will cause the carb to misbehave. Perhaps it is worth taking to a local mechanic, just to have him turn the various screws and widgets back to stock settings - and, perhaps more importantly, to get the piece of mind that the unit is basically OK? In other words, I would not buy new parts before ascertaining the old part is defective, instead of merely out of tune. Quote Link to comment Share on other sites More sharing options...
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