running too rich

[Zooted_plus]

I can't seem to get my carb to lean out.... Carb is a holley 4160 list # 9834-2
Ive checked both float levels and both are right below the check screw when the car's running. Idle screws are turned all the way in and have no effect on the idle. I had it on the gas analyzer at work and it was like 6,000 ppm HC and 12% CO... it almost broke the machine! Also fouled my oil. Any ideas on what could be causing so much extra fuel? I don't want to wash my cyl walls.

 

[68GEETEE]

I cant really help you other than to say that my 4160 did the same thing. I never found out what it was, instead I slapped a brand new Holley on, and I still have the 4160 in my garage, I am pretty sure it is in need of a rebuild.

 

[hummer784]

Hey man, did I sell you some jets today at monument?

 

[Zooted_plus]

yeah thats me, bought the holley trick kit, jets and oil pressure gauge.

 

[10secgoal]

CHECK YOUR POWER VALVE!!!!!! Pull it out and suck on it. Yeah it's nasty but that's how to check. If it holds vacuum, then replace the gasket. One of them is leaking. I bet it smokes real nice at idle huh ? Your carb is drawing extra gas somewhere. With idle mixture screws all the way in, it should die. If that doesn't solve it PM me.

 

[rbohm]

first thing is to check the metering block mounting surfaces for flatness. if they are not flat then fuel will transfer to the wrong passages and cause the very rich mix you have.

 

[mustangracer]

I'd second both suggestions, and it could be as simple as a pinched gasket somewhere. There is enough of them in a holley. Could also be a problem with the base gasket. You could spend a lot of time replacing everything piecemeal, but prolly easier just to do a full rebuild.

 

[65 project]

Is this a used carb you just installed, or a new one? If used, did you do a rebuild on it? How long have you had it? If you bought it used and just installed it, you probably better put a kit in it and also check the jets to make sure they are the right size for that Holley.

 

[351LX]

If your secondaries are open too much then you won't see much effect when you try to adjust your primary side.There is a little screw at the bottom of the baseplate that controls how much the secondary side will be open,I usually adjust mine so it is just at the bottom of the idle transfer slot.Most Holleys have a secondary idle circuit that is not adjustable.It is there to keep fuel flowing through the secondary side bowl so it doesn't go stale but if your secondaries are not properly set you will be running off that circuit.

 

[sportsroof69]

Check the O-rings on the small transfer tube between the metering block and main body. Use Vasoline or some other lubricant on the power valve gasket and O-rings to prevent them from sticking. I have had several power valve gaskets split in half around their circumference. They look OK until you pull the valve. Filing the main body gasket surfaces is also a good idea. You will be surprised at how uneven the surface is.

 

[Zooted_plus]

Thanks everyone for your replies, some good ideas in there I hadn't thought of... I will be checking and replacing the power valve, checking metering blocks and baseplate with a straight edge for warpage, secondary circuit-- also making sure the secondaries are closed at idle, also replacing everything that comes in the trickit, and possibly re-jetting.

The carb was used, I picked it up off ebay for $38. The guy who helped me rebuild it initially (about 3-4 months ago) said that it had never been rebuilt cause it had all holley parts and gaskets. I threw a nice AED rebuild kit also aquired off ebay, it had all the gaskets, pwr valve, needles&seats, idle screws, accel pump squirter, accel pump parts and vacuum secondary parts, nylon washers, etc.

Jets. Let me just say I don't have too much hands on with carbs. I can adjust a/f mix and idle speed no problems... when it comes to troubleshooting a driveability problem with a carb... forget it. However, I'm trying to educate myself where I am lost. I know jets meter the amount of fuel. Similar to what metering rods do on an edelbrock or a quadrajet... but jet sizes I know nothing about. I would assume naturally a numerically high number would be a bigger jet... so I went with the smallest ones I could buy and got 122-62s.
Hopefully I didn't make a bad choice.

 

[10secgoal]

AED ?!?!?!? Throw that power valve gasket OUT!!!!! I just put one of those power valves in and chased the same exact thing for three days . Put in a stock holley paper. Thier gasket comes with four small holes in it for early metering block to pwer valve alignment. The metering block won't seal over those holes. TRASH THAT GASKET !!!!!

 

[Zooted_plus]

The nylon power valve gasket? Rebuilt most of it today, used the holley paper, also replaced the two o-rings on the transfer tube above the pwr valve, used gas instead of vasoline, put new needles and seats in, new gaskets on the idle mix screws, blew out all idle passages w/compressed air,
then got caught up in the parts breakdown.

When I took the carb apart the first time I don't remember there being a check ball underneath the accel pump discharge nozzle. Just a small peice of metal that looked like a bullet. Was the carb missing a check ball? or does that bullet thing do what the check ball does? According to the breakdown/diagram, there should be a check ball, ball weight, then the conical bullet shaped thing, the nozzle, and screw to hold it all in.

 

[10secgoal]

Yep. That's all it needs. I have a proform main body, and that's all they gave me. I'm telling you, it's that god !@$* power valve gasket. Now that it's out, look at that gasket. There should be a ring on one side where the metering block seals. But you'll see the four holes I'm talking about. P.S. don't look at the directions....( sounds stupid I know) but that one sheet covers many many model numbers. Replace it with what came out.

 

[10secgoal]

Well, well.. Any luck yet. hehe I want to know if that gasket got you , too !!

 

[Zooted_plus]

Well, well.. Any luck yet. hehe I want to know if that gasket got you , too !!

I put the carb on last night and messed around with it. I had the idle mixture screws 3 full turns out on each side, fired right up, idled too high so I lowered it.... didn't smell too rich at first, but then idle speed dropped, it started smoking and died. All is good though, I don't think its dumping extra gas in like before.


When I turned the idle screws in one and a half on each side, the car wouldn't run. Put em back out to 3 full... drove it today, idles better, no more surging. I didn't get a chance to put it on a gas analyzer and tune that way... I think you're right that gasket was split or just altogether no good.

So the moral of this story is: DON'T BUY AN AED CARB REBUILD KIT!!!