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Author Topic:   Motor Question
whitesracing
Dirt Maniac

Total posts: 121
posted April 28, 2005 04:00 PM  
Ok Guys

Needing alittle help here. I have a motor which is a fresh built.I have had it running couple of times. Each time,I have fouled the plugs so bad the motor runs rough.
I have a 4412 holley carb , motor is 60 over, pistons 4 valve reliefs, so nothing big.
No big cam.
Timing is right on the money .
when it is running i realy dont see any amount of black smoke , but when i pull plugs the tips are solid black.

where would you start?

---------------------------------------------

Thanks all that offered help
runs like a champ

[This message has been edited by whitesracing (edited May 03, 2005).]

Steve Dupree
Dirt Freak

Total posts: 316
posted April 28, 2005 04:19 PM  
I would diffently look at carb we run like a 72 jet max. in are 4412 on a 351w 9.5 /1 It could be more in the carb. besides jets see if you cant borrow one and try it or change jets to 70 and go from there. Other things to check: setting on accelerator pump,power valve or float level. Hope this helps

whitesracing
Dirt Maniac

Total posts: 121
posted April 28, 2005 04:21 PM  
well check float level , is was correct , checked jetting they are correct .


Donnie Ross
Dirt Freak

Total posts: 264
posted April 28, 2005 04:21 PM  
first if you are running a power valve check if it is correct for your engines vacuum,not busted, or(very common) the gasket didn't slip out of place when installing the valve,check float level, verify fuel pressure is not to high (6 psi is plenty)assuming all these are correct start jetting her down a couple of sizes at a time. suggest starting with 78 jets not to fat or lean for aball park start. good luck.p.s also make sure idle is adjusted correctly not just turned up till it stays running, I beliieve i/8 inch transfer slot exposed not 100percent sure on that one, no fuel should be coming from the boosters at idle.

racer17j
Dirt Forum Champ
Total posts: 5390
posted April 29, 2005 06:37 AM  
That's what I would ask too. What is your plug gap and what octane are you running?

leapinlizard
Dirt Freak

Total posts: 402
posted April 29, 2005 08:15 AM  
Are the plugs black dry or black wet? Are there any signs or of a white/tan/brown buildup?

whitesracing
Dirt Maniac

Total posts: 121
posted April 29, 2005 02:51 PM  
ok Battery fully charged ,
PLUGS a/c 44ts
gap .45

Plugs are black dry
There is no sign of white or tan , BLACK THATS ALL.

car runs great after fresh plugs , after running a few minutes you can tell differents on how motor runs

[This message has been edited by whitesracing (edited April 29, 2005).]

Raceman17
Dirt Maniac

Total posts: 165
posted April 29, 2005 02:56 PM  
To properly check the plugs the motor needs to be shutoff on the racetrack when at full throttle after running a few laps. You then either need to coast to the pits or be pushed. If you are checking the plugs after you have been idleing around for a few minutes this will give you false readings.
Later


quote:
Originally posted by whitesracing:
ok Battery fully charged ,
PLUGS a/c 45
gap .45

Plugs are black dry

car runs great after fresh plugs , after running a few minutes you can tell differents on how motor runs



whitesracing
Dirt Maniac

Total posts: 121
posted April 29, 2005 02:59 PM  
wish i could get it out of garage first , track sounds great ...lol

[This message has been edited by whitesracing (edited April 29, 2005).]

racer17j
Dirt Forum Champ
Total posts: 5390
posted April 29, 2005 03:33 PM  
Sounds like too much jet

Eljojo
Dirt Forum Champ
Total posts: 968
posted April 30, 2005 05:04 AM  
It sound like there is fuel bypassing the needle and seat and flooding the cylinders. Pull your dipstic and see if your fuel is smelling more like gas than oil.
New oil and filter $25
Rebuild carb $35
Racing on Saturday night....priceless!

Ego Racing
Dirt Forum Champ
Total posts: 724
posted April 30, 2005 05:43 AM  
Check the ground wire on the battery and the ground path to the motor. We had a LM that fouled plugs really bad and the last thing we did was run a ground from the ground connection to the frame to the engine. When we tried to check it out with a volt/ohm meter there was very low ground potential on the engine, the powder coating on the chassis was acting as an insulator and the motor was not getting a good ground.

regal 22
Dirt Full Roller

Total posts: 28
posted May 01, 2005 06:33 AM  
the same thing happens to me, I found that I let the car idle way to long, trying to make
sure the car is right for the track, wish I had
a spark plug cleaner, would save a lot of money.

dirt_mopar99
Dirt Forum Racer

Total posts: 94
posted May 01, 2005 06:44 AM  
Try Autolite plugs

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Speed Kills, Drive a Chevy and live forever!

whitesracing
Dirt Maniac

Total posts: 121
posted May 01, 2005 05:40 PM  
Ok Guys ,

Im still having troubles.

This is what i have done.

Tried Autolites- #26 FOULED them as soon as I Fired motor. Set gap at .045

I had battery charger on to make sure i had a hot battery.

I have a new cable going from battery to motor also have a one from frame to motor.

Checked float it was alittle high , but adjusted it back down to where it just runs out.

RECHECKED TIMING !

I put New plugs in , fired motor. I pulled plugs after it ran a few minutes , ran motor up to around 4500 rpms an shut motor off.Plugs are a Dry black color, the whole tip. I noticed when motor was running looked under and seen Black smoke coming from both sides. The smell , smells like to rich The jets are 72. When motor is running it makes your eyes burn. Fuel pump is stock.so pressure shouldnt be high.

What am i not finding ?

As you see i am trying everything you guys are offering.

Raceman17
Dirt Maniac

Total posts: 165
posted May 01, 2005 06:53 PM  
When the motor is running at idle look down the barrels of the carb and see if gas is dripping from the top things in the carb (I dont know what they are called) they should not be dripping any fuel when it is idleing. If it is, turn the idle down.
Have you changed that power valve yet? Also changing the jets will do nothing when the car is sitting in the shop idling. You still need to get it out and put the motor under a load to see how it is doing.

Raceman17
Dirt Maniac

Total posts: 165
posted May 01, 2005 06:54 PM  
When the motor is running at idle look down the barrels of the carb and see if gas is dripping from the top things in the carb (I dont know what they are called) they should not be dripping any fuel when it is idleing. If it is, turn the idle down.
Have you changed that power valve yet? Also changing the jets will do nothing when the car is sitting in the shop idling. You still need to get it out and put the motor under a load to see how it is doing.

tom waara
Dirt Roller

Total posts: 19
posted May 01, 2005 07:09 PM  
[QUOTE]Originally posted by whitesracing:
[B]Ok Guys

sounds like your power valve is blown

whitesracing
Dirt Maniac

Total posts: 121
posted May 01, 2005 07:57 PM  
OK put smaller jets just to see what might happen , now have 67 in carb ,

also looked down into carb , no fuel leaking , only time see fuel is on acceleration.

also tried another power valve , still seeing alittle black smoke coming from exhaust.

took carb apart , used air to blow every hole an check needle an seat , carb had plastic , float , had a brass one , installed it .

what is a common power valve used ????

If anyone has any idea , please throw them just way. Money spent on plugs out due fuel spent going an getting them.

SOMEONE ADVISED ME USING AUTOLITES 104
I AM GUESSING A PEANUT PLUG AND HOTTER ?

stockcar5
Dirt Forum Champ
Total posts: 578
posted May 01, 2005 07:58 PM  
a good size is 6.5

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www.geocities.com/dirtstockcar5

[This message has been edited by stockcar5 (edited May 01, 2005).]

nailngoracing
Dirt Maniac

Total posts: 170
posted May 01, 2005 08:54 PM  
try blocking off power valve for now...just to eliminate it from the worry list

El Santo
Dirt Full Roller

Total posts: 36
posted May 01, 2005 11:01 PM  
Make sure the power valve is getting vacuum through the vacuum supply hole in the carburetor. The hole should be unrestricted from the bottom of the carb into the power valve chamber in the center section of the carb, unless you have a blowout protection check ball installed. I have seen these check balls stick and cause the power valve to be open all the time. Also what intake/spacer combination are you running on this engine? There could be an issue there.

rockinron
Dirt Full Roller

Total posts: 30
posted May 02, 2005 12:41 PM  
Maybe this will help. You said that the exhaust smelled real bad. Check your fuel for water. I dont know if this will make your spark plugs black or not though. Just a thought.

KKKK
Dirt Roller

Total posts: 9
posted May 02, 2005 01:28 PM  
It sounds normal to me. Our car seems as if it is running rich at an idle - black plugs, burns eyes, rough idle, etc. Get it on the track and it hauls arse!

dm3
Dirt Full Roller

Total posts: 40
posted May 02, 2005 01:49 PM  
Do you have anyone that can loan you a carb to be sure it's the carb? It's not likely that bad rings or valve guides would foul out plugs that fast without a lot of smoke. But, it seems that you've done about every carb check I can think of.

whitesracing
Dirt Maniac

Total posts: 121
posted May 02, 2005 02:25 PM  
OK guy ,

want to hear something funny , i pulled a vacum cap off the lower part if carb and it had gas in it.

why would i have gas there ?

im going to try the other stuff and let you all know something got to give

eenfield
Dirt Maniac

Total posts: 116
posted May 02, 2005 03:32 PM  
OK...If you had it apart for whatever reason BEFORE had these problems, then you may have gotten the wrong metering block gasket(s). There are more than one gasket in the kit so as to fit more then one carb. Get the wrong one in the carb, and you can experience the same type of problem.

For for guy who said that he thought there should be approx. 1/8" of transfer slot showing, I believe that there be no more then .030" of the slot showing...

Donnie Ross
Dirt Freak

Total posts: 264
posted May 02, 2005 06:34 PM  
thanks wasn't sure of the exact figure,just that if it was to much you would be in the main metering circuit instead of just the idle circuit.

whitesracing
Dirt Maniac

Total posts: 121
posted May 02, 2005 06:52 PM  
question :

About how many turns should there be on the fuel /air mixture screws. Currently there is 1 1/2 turns out from all the way in . Does this sound correct? Would i need a vacuum gauge to maybe set this correct?

Carb was fine when i took it apart , I took it apart to see if i had dirt or something stuck causing it to flood . I changed the float because of it being plastic in case it might of been causing the float to hang open.

I cant figure out why i found fuel on the vacuum port at the base of the carb. why would there be fuel there when it should be vacuum ? It should of pulled it back into the motor not let it sit there correct.

I have a 4 bbl intake with a Phenolic spacer under it.

I have looked down inside the carb as it is running , no extra fuel leaking. only time i see extra fuel is on acceleration, then you see extra fuel.

tom waara
Dirt Roller

Total posts: 19
posted May 02, 2005 09:04 PM  
[QUOTE]Originally posted by whitesracing:
[B]Ok Guys

if you turn the Idle mixture screws all the way in, it should starve for gas at idle and stall out. does it? if it don't fuel is coming from another part of your carb.

Steve Dupree
Dirt Freak

Total posts: 316
posted May 03, 2005 08:35 AM  
You know the idel mixture has nothing to do with the car when its under acceleration. What we do is drill two small holes on the butterflys in the primary shoot. No bigger than a 1/8 This will let it idel with more air and you dont have to worry about idel screws.

eenfield
Dirt Maniac

Total posts: 116
posted May 03, 2005 09:01 AM  
You didnt mention how much of the transfer slots are showing. They are located in the bottom of the throttle bores (visable from underside of carb) in the front. They are small little slits approx .020-.030 wide. You should have about .030 of the slot length showing. If you have more than that you should examine why. If you do then you should turn the idle speed screw in until they are coverd up to the above mentioned spec. If the engine wont idle then you need to see why. Is your timing correct? Are your idle screws way out of whack? Power vavle bad? Float level wrong? Have you actually checked that your fuel pressure is not too high? Is your needle and seat really good?

If there are any more suggestions I'm sure someone willl bring it up.

If you have fixed the problem, but it to idles low then you can make MINOR adjustments to the idle speed screw 1 1/2 -2 turns max to raise it. If high then simply lower it.

If the above things did not fix it then you can try drilling a 1/8" hole in each one of the butterflys. This will move more air through the carb without showing more transfer slot. (transfer slot is reponsible for metering low speed fuel, not idle)

Clyde Torkel
Dirt Full Roller

Total posts: 33
posted May 03, 2005 01:18 PM  
You said you saw fuel when accelerating. Watch the accelerator pump squirters when you accelerate slowly up to about 4500/5000 or so. If you are still getting fuel out of the squirters post back and let me know. This happens mostly on 4 cylinders but it can happen on other engines too. There is a fix.

whitesracing
Dirt Maniac

Total posts: 121
posted May 03, 2005 05:00 PM  
Ok Guys

Fisrt off let me thank everyone that has offered help.

Today i went and bought a new rebuilt kit

First off all gaskets where correct.

REMOVED EVERYTHING .

Washed it out , checked anti blow ball for power vavle that someone had installed.It wasnt stuck could spin it.

I installed new power valve , accel pump which was a 50cc.
new bowl gasket , new meter block gasket

I installed a vent tube so if fuel level was to high wouldnt pull from there.Also someone had already drilled the butterflys with a 1/8 hole . SO i guess this rules out air/fuel mixture screws.but installed new ones anyway.

STUCK IT ALL BACK TOGETHER AND THE THING RUNS LIKE A RAPED APE.
Checked plugs and they are finally showing a lite brown color.

So i thank all that replied , will keep everyone updated as we get going.


    

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