Fuel system and pressures HELP!!!! Please !!

[wismadman]

I switched engine builders and was told to update. (private builder) Sold carb and bought new high volume fuel pump with a newer K&B carb. After like 10 nights and two engines I had to call it a season with no money to keep going.
Started out with a 2nd but the air cleaner started on fire a little so I had to adjust some things. Everything I tried just got worse. Had a rebuilt CV pump on and it made too much pressure at a dead head. I tried a new regulator and by passed fuel back to the cell and was told to run like 7/8 pounds. To make a long story short.......I tried a different CV pump. I tried different regulators. Went back to a cheap holly/ carter low volume pump. bought new fuel lines. pulled fuel filter apart. Pulled (top feed) fuel cell apart. Sent the carb to K&B to look at and rebuild. Ran fuel in and out of carb and regulator every way you can to have nothing but problems.
At first, engine would die trying to put heat in tired. Fell on face. Floats too high ? Then the car wouldn't start without 3/4 throttle wouldn't idle. Than after getting heat and get in line up it would quit. a mother to get started and wouldn't run unless it's at 3000 rpm. fuel pressure would drop as it got hot. dripping fuel out the top of carb. Tried turning fuel floats down. I mean the whole season/ all 10 nights was fighting fighting and more fighting fuel problems. The only thing I couldn't do was put old carbs on that I sold and I was broke. (Blake and Braswell)
So if anyone can help me with the newest and greatest with these cars rolling over on the right front and messing with the carb or not would be greatly appreciative. I some how cracked one block behind a cylinder and pushed water pass the cap and burnt a hole in a piston pushing (not a nice word)(not a nice word)(not a nice word)(not a nice word) loads of oil out the rear main on #2. Both engines are alum dart blocks and 18 degree heads. I'm running vp 114 racing fuel. Been at this for 16yrs and I've never been so frustrated!!!!

[rakracing]

sounds more like a vacuum leak more than anything, it wont idle, and leans out and burns pistons check the intake good and check the intake gasket maybe the intake and head aint matching, dry or wet sump

[keeks]

Gas or Alky?

[Kromulous]

Gas or alky, yes?

KSE belt drive or off the back of the dry sump pump.

I would never on purpose run any sort of mech pump, ever, ever x 10, & ever again.

[billetbirdcage]

I'm running vp 114 racing fuel.



there is your answer

[petesbuyin]

Been at this for 16yrs and I've never been so frustrated!!!!So you're a rookie at this then? Just kidding. I have been at this just about triple that amount and it still frustrates me some times. The very first thing i would look at is that you have the correct gasket between the base plate and the main body. If you have the wrong gasket it will block off the idle passages which will make the engine very difficult to start and near impossible to run under 3000 rpm. If you can get the motor to run enough to get it on the track it will run real lean and want to die every time you let off to enter the corner. I have seen very talented carb builders just grab the wrong gasket and make this mistake.

[dirtrace09]

I would start at the fuel cell and check every single connection all the way to the carb. I have seen a system pull air from fittings that people swear are good, tight, etc... Air leaks act this way.

[wismadman]

The die thing comes and goes. throwing the car back in forth to get heat the engine would die till the car leveled out. What am I looking for in this gasket? My engine builder took it apart twice and so did the carb person. just don't get why the fuel pressure goes down as it gets hot. electric gauge and mechanical .
I took the whole fuel system apart. It's like the carb or something.

[Brian Gray]

Get an Afr gauge.

[keeks]

If you have jet extensions on it, make sure the float isn't hanging up on them.

[50j]

I have seen this several times too. It can be fittings not threaded in far enough, bad lines, even a crack in the pick-up tube or the tube floating to the top. If pressure changes when it gets hot, it's probably sucking in air or boiling the fuel if lines are close to headers or a radiator hose. Putting a known to be good borrowed carb on for a night wouldn't be a terrible idea either. If you use a different carb, make sure it suits your engine and fuel. Your engine builder may have one, or possibly another racer with a very similar engine and the same fuel.

[pfd60]

Make sure you have a -10 going back to cell and a working bypass. I had the same type of pressure differences. It took me four nights to figure it out. The bypass was my problem.

[wismadman]

I didn't look at the alum tube in the cell. I don't know the route with the high volume pump. When does the regulator go into the system. What regulator? 2 or 3 port? size of line? pressure at idle pressure at 3,000? thanks again. Going to try to buy new msd and coils to take out that problem.

[Lizardracing]

Electrical Problems are the easiest things to fix and don't usually cost much if anything. Some ideas are....Plates in the battery loose or broken, I've seen ignition switches fail with broken poles on the inside, Zip ties cutting through the wires, loose or corroded terminals. I hate the crimp on stuff. I always solder and heat shrink everything. I'd pull every connection and sand both sides of the connections. At the very least your eliminating any future problems that seems to creep up at the track and not at home in the shop.

Like above, I'd check every fuel line connection including the cell pick up tube in the cell and the roll over vent. I'd change the filter and the pump push rod. I'd check the pump push rod travel too in case the cam lobe went flat. I'd look for broken valves or trash in the valves in the pump. I'd replace the needles and seat with Holley brands only. The float drop is very important and often overlooked. Replace the Power valves and blow out every office and holes and tube in the carb paying much attention to the idle air bleeds and restrictions. Take you sweet ass time and work alone without distractions and I think your bound to find your problem even if you don't find anything obvious sometimes cleaning up all the little details takes car of it.

[ALF401]

We ruined an engine once and finally found out the pickup tube in the fuel cell (fuel pick line ran out the top) had a small crack in the fuel hose at the inside top of the fuel cell. Gas in the carb like you described the whole time!! When we put a new engine in, we ran the fuel line from a fuel jug by the right front tire and it run great. Put the regular fuel line from the fuel cell and old problems started again.

[petesbuyin]

The die thing comes and goes. throwing the car back in forth to get heat the engine would die till the car leveled out. What am I looking for in this gasket? My engine builder took it apart twice and so did the carb person. just don't get why the fuel pressure goes down as it gets hot. electric gauge and mechanical . I took the whole fuel system apart. It's like the carb or something.This is the difference between the two gaskets. Notice the position of the small holes. But after reading more of your posts, I don't think this is the problem. If you have the wrong gasket it will run bad all the time, not come and go. To break a piston is generally too lean or a timing issue. i agree with you about looking at the ignition system. With a MSD be sure that the pickup wire from the box to the distributor (or crank trigger) is NOT near the coil wire or any high amp draw wire such as the large red wire on the MSD box or the RF shut off valve. Just being close to these wires can cause an induced spark and erratic running engine. http://i873.photobucket.com/albums/ab291/Pete79L82/gasket_zps6ksb6knw.jpg (http://s873.photobucket.com/user/Pete79L82/media/gasket_zps6ksb6knw.jpg.html)

[wismadman]

still killing me GRRRRRRR

[RCJ]

Do you think it is a carb problem? Run ok on the track at speed?

[powerslide]

Where are you from? Maybe someone is willing to loan you a carb to try if you think that might be the issue.

[wismadman]

just seen that the carb is making little bubbles in the bowl during higher rpm. coming up the bottom of float. I put hose clamps on my push lock feed line since this. Have not bumped the fuel pressure up to 8-9 yet to see what happens. was around the 6psi mark at 5000rpm. Electric gauge, mechanical is bouncing from 3 to 6 on the fuel log.

[RCJ]

I 've used 1 kb carb on the dyno, while it made good power it was lean and would not respond to jet changes as it should have.IF the carb will not idle check that it has a small hole drilled in each throttle blade.Turn the carb upside down and you will see a small slot by the blades.the slot goes up and you will have to open the blades to see it.Adjust the idle speed screws till you have about .040 of the slot showing below the blades.Check the ldle air bleed at the top of the carb(outside jets)they should be around ..070 ,smaller makes it richer.