Has anyone delt with the Edelbrock AVS? I've been looking at that carb for the last day or so. I just don't want to buy a new carb when I may just need to tune mine some more. Then again maybe I just happen to have one of those Holleys that refuse to be tuned and it likes to watch me get fustrated. My truck is back to being rich again and I'm running out of patience with it. I'd like to return the carb to the store via the front window like that old tire comercial.

 

Have you checked the power valve? What size is it? Should be a 6.5 or lower. Has the engine back fired? This will blow the valve if not protected. A bad power valve will make the engine run rich at all speeds except WOT. Quick test is at idle, screw the mixture screws in to less than half a turn out from seated, if the engine still runs, valve is blown.

 

I'm really hating this Holley. I just rebuilt it about a month ago and put a new 65 power valve in it. Well I did your little test and ended up screwing the mixture screws all the way in and it ran a little lopey but ran none the less. good thing I have an extra 65 power valve. I guess I have an older one without the power valve protection. Looks like I'll be heading to checkers for those gaskets after all. Anything else I should check or replace while I have it open again?

 

Ok I just tore my Holley to pieces. Here is what I found: I do have a good/ clean check rod under the squirter. I also have the check ball in the vacum housing. The vacum diaphram wasn't sealed all the way around the housing though. One side from screw hole to screw hole was laid over on itself in a manner in which I don't think I had proper vacum secondary operation. I have a silver spring in the vacum housing. There appears to be a check ball located behind what looks like a jet in the base plate. Is that the power valve protection ball? Also I was cleaning the main body and found 3310-4 but it has two metering blocks. So what's the deal? Do I have a 3310-4 with a metering block conversion or did someone swap a 3310-4 main body in (which I doubt)? I have my choke wired open year round. Is there a way to remove the choke completly so I don't have that ugly clothes hanger rod holding it open? It looks like I could use a punch and gently knock the shaft back through the choke tower causing the choke blades to slide off the shaft. Is this the correct way to do it if it's even possible? Or should I just cut it off or just leave it? I don't use it at all in Az. Also I got a one gallon can of chem-dip carb cleaner but the body and base plate don't fit. How do I properly clean the passages in the body and base plate? I have access to a hot tank, can they be hot tanked? Also the metering rods in the bowls were almost black from grin and what looks like carbon build up. I have about a dozen new ones in the trick kit but the old ones don't seem to have any size indicators on them. Which size do you guys recomend? Sorry for so many questions. I just didn't have this much stuff with the first rebuild kit and I didn't realize how much stuff was left out of the first kit.

 

I was unaware that any 3310 Holley had metering rods anywhere in the carb. The choke valve is held in the shaft by 2 screws with the ends spread. Just remove the screws and the valve will slide out, the remove the shaft. You will pick up some CFMs with it gone. Carb cleaner should work with letting it soak overnight. Hot tanking is bad for aluminum castings, don't do it. The black stuff in the bowl is what is causing your problems in the rest of your carb, the gas of today sucks and is trash. The cleaner should remove it.

 

Sorry the proper nomenclature is fuel inlet & valve seat assembly not metering rod. This is my first Holley and I'm used to Edelbrocks. Was being lazy and didn't want to dig out the instructions again. Looking at my instructions I see the two screws you are talking about. However looking at my carb I can see I don't have two screws. The choke shaft appears to have a slit in it from side to side. The choke plate seems to slide through the shaft and looks to be held in place by two little tabs on the top and one long tab on the bottom. I may just take the die grinder to it and carefully remove the top tabs and try sliding it out unless you know a better way? I don't have a metal container big enough and the girlfriend would kill me if I used one of the pots to soak a carb over night. Any other suggestions?

 

Looking at my instructions I see that I'm missing number 75 and 76 on the diaghram.

#75: pump check ball weight
#76: pump discharge nozzle check ball

Could that be the cause of my problems? I have #74 which is the pump discharge needle valve. My instruction state that my carb may or may not have all pieces shown since it covers more then one carb. Should I have #75 and 76?

 

The system uses either a needle valve or a check ball. I never had a problem leaving them out. So it you have either one in there you should be good to good.

 

Ok I put the 5.5 power valve in and reassembled the carb paying special attention to everything. I spent 6 hours just making sure I did everything correct. I set the floats and the idle mixture screws. I set the secondary grub screw. I cleaned and checked every single piece. I get it all back together and what does it do? It BACK FIRES. Yep first turn of the key after getting the carb primed and POW. It starts and I turn the idle mixture screws in to see if the power valve is blown. Yep turned them all the way in and it still runs. Rather nice running at that. I have a vacum leak that I missed some how. Too dark to find it though. I have decided to sell the carb. I'm going back to Edelbrock. If I still have problems with the new carb I know a guy who really wants to buy my truck.

 

You have to have a timing issue or a vavle timing problem. You should be getting back fires on start up and why did you not install a power valve protector when you had it apart. After I started installing them I haven't lost a valve since. Long ago in a galaxy far, far away, my '68 F250 390 4V with 3 tanks and no gauge on the saddle tanks would usually backfire after I ran out of gas in either saddle tank and switched to a full one when fuel came back into the carb.

 

A 3310-4 has the power valve protection from the factory, but someone has added the secondary metering block. You should have #72 primary jets, number 65 power valve, a 31 pump shooter, and a plain(silver) secondary spring. Those are the factory settings for the 3310-4. A #75 secondary jet is equivalent to the secondary plate that was stock.
To remove that style choke plate, you push it thru the shaft which will spread around the plate and then remove the choke linkage and shaft. Keep it all together in case you need to sell it

 

If the carb came with a protector and he blew the power valve when the engine hiccupped then the protection device is not working and needs replacement.

 

Agreed, Bear. However I don't know if we ever determined the power valve was blown??

If you turn the idle mixture screws all the way in and it still runs, it is running too RICH. One cause of which is a blown power valve. A vacuum leak will cause it to be LEAN. I wish Bear or I could look at this carb, it is beginning to sound like it has been messed with. It might be that it has had a few "adjustments" to the air bleeds, PV restriction, etc.??

 

It was messed with by the previous owner. He did the metering block swap and swaped out the primary jets for smaller ones. I'm guessing he got rid of it for the same reason I'm having trouble with it. I did finally get it working last night. I changed the springs and bushing in the dist. Then I checked and reset the floats again. It ran great other then a very minor of idle hesitation. I went out this morning and it wouldn't idle or run for anything. I even tied to hold the gas down alittle. At 3000 RPM it sounded like cr*p. Sputtering and everything. I adjusted the idle mixture screws alittle this morning since I don't have the gauge at home and checked the floats. It was out of wack again. I have it running really good right now and I'm on my way to the auto hobby shop to set the timing and idle/idle mixture the correct way. Hopefully it will run good tomorrow when I get up. That will be the real test.