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Discussion Starter #1
The other day I posted a thread about leaking Holley 4160 carb. I later realized that all the gaskets probably should be replaced. Never doing a rebuild I was hesitant,but said,"go for it". Anyways after some research, I bought the rebuild kit and rebuilt it (I think), last night,and finished today. It took like forever, because I did each step slow and carefully, following steps that I printed out from the internet. First I dont know why there are so many kits from Holley, when it seems they have all the parts for every carb in each kit! I hate to have so many things left over, not sure if anything was missed. But Im sure used all that was meant to be used.(except for 1 small gasket that was missing. I reused the old one) Anyways, I got the carb on and sat there thinking I dont want to try to start this up and realize too late (while fighting a fire),that I did something wrong. Well after a short cranking time the car started and ran for like 5 seconds and stalled. I cranked it some more to no avail, and then took a look at the carb and was glad it didnt start! There was fuel sitting on the intake, and It appears it all came from the top of the carb ,since it too was soaked with fuel! :( Obvioulsy I am pissed and stumbling to figure it out. I did a search and am thinking it may be a float problem??? One thing Im not quite sure is how to adjust the side mounted floats, since it seems the directions to adjust the floats are for the center mounted ones. They say to level the float. What I did was the dry adj, to where I put the top edge of the float, farthest from the pivot ,equal to the bottom edge of the sight hole.(it was turned upside down making this adjustment) Im hoping I did this wrong and it is the problem:) I cant do the sight adjustment obviously, since the car isnt running. The floats are not new and were in good working order prior to the rebuild, so its not the floats themselves. They were moving freely when I reassembled them, so they arent stuck. Any ideas to why the whole carb got soaked? Should I maybe disconnect the coil wire and have someone crank it to see where the flood is originating from? A cold one goes out to the problem solver:D Thanks !!
 

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remove the needle and seats and make sure they don't have any junk stuck inside them. Then from where you had the float set drop the level down 1 full turn. That should be plenty. Then try again. The gas will evaporate after a while.
 

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Discussion Starter #3
The needle assemblies are new. They were in the kit. Just one set,so I assume they are the right ones.
 

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Your problem seems to be float related.

Adjustment?

Float is bad?

Needle and seat is bad?

Did you reinstall the covers around the valves? Side pivot bowls have a plastic cover to retain the fuel spray. Without them the fuel pressure entering can disturb the float itself. Pushing it down, multiplying the problem.

Al

PS: Kits have extra parts to save you money! This reduces the amount of part numbers needed for kits. Making a part # a faster mover and reducing the cost of inventory and cost to consumer.
 

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Discussion Starter #5
Big Al, covers are on, floats were fine before. The needles are new. I pull it apart and look again.
 

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just becasue it did not leak before means nothing.

Changing the needle and seat requires re-adjusting the float location.
 

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OK!
Things I want you to check.

Remove the fuel bowls.

This is the bowl in upright position



This would be the bowl upside down.
Doing this see the position of the float bowl, in this position you can see the location of the float with the needle valve closed.


With the bowl upside down, adjust the needle valve until the float is in this position. This will be a low setting for the fuel level. This will allow you to bring the fuel level up using the site hole as in the instructions.
Also remember the adjustments are done very slowly and patently. Also if you go to high, the carb must burn off the excess fuel. The fuel level will not go down because you adjust it down. The carb must burn it or you must drain the fuel and start over. You can drain the fuel removing a one of the lower screws that holds the bowl to the carb.


Hope this helps
Al
 

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Discussion Starter #8
Thanks Big Al for your photos and effort to help! Earlier this evening I did some more searching on how to adjust the side mounted floats and found this,http://www.centralhp.com/PDF/catalog/156.pdf
I did what they described in the 2nd paragraph. But before I did,after I took the carb back off and took the bowls off, turned them upside down, and I could see immediately that my guess adjustments were way off! I might as well of just put the fuel line hose directly into the top of the carb, as my guess adjustment had the floats set about 1/2" high in the inverted position, compared to thier 7/64"!:eek: I basically was supplying way more fuel than the carb could possibly use. I am waiting until tommorrow to reinstall the carb and try it out. I wish I had seen this initial adjustment link beforehand, but am sure I have solved the flooding problem. I just hope this is the worst of my problems with this rebuild.:)
 

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not to thread jack but I have a question. On the transfer tube are you using an O ring or the other type seal that is super hard to get the tube in and can't get the bowls back on?
 

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Discussion Starter #10
not to thread jack but I have a question. On the transfer tube are you using an O ring or the other type seal that is super hard to get the tube in and can't get the bowls back on?
I used the new o rings included in the kit. They are snug. I slid them on the tube, and lubed the o rings with a dab of oil. I still was snug, but it popped into place. I think if you put the o ring in the bowl first, you will chew it up trying to get the tube in. Thats why I put them on the tube first. I attached one bowl to the carb, put the tube in it, then aligned the other bowl to the tube and holes and worked it on.
 

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On a side note, I've found those O rings work great as bowl screw gaskets, they last a lot longer than those stupid paper ones.
 

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Obviously you put new parts in, but how did you clean the main body, the metering blocks, bowls, etc. In my experience, the most important part of rebuilding a carb is making sure that everything is absolutely clean! You don't want a piece of crap coming loose from inside and sticking in a passage, or holding your needle and seat open.
 

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Discussion Starter #14
Chuck, The carb was pretty clean to begin with, but I soaked parts and brushed them initially with carb cleaner, then lacquer thinner, then reshot carb cleaner thru the passages, and finally used compressed air to blow them out.
Well ,Today I put the carb back on after resetting the floats. I made sure the needles were not sticking also. Well, I got fuel blowing up thru the secondary vent tube!:mad: Looked like a damn water fountain. Gotta pull it off again!:mad: ??:confused:??? I thought wrenchin' was supposed to be fun!:)
 

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Discussion Starter #15
Well I think I found the problem. After I inspected the secondary bowl, all parts were working normally. Then I noticed on the float, real light scuffing. Then looking at the secondary metering block I noticed a small burr. So what I did was turn the bowl and carb so that the float would be up in the bowl when I put the two back together. Then I inserted 2 bowl screws, and set the carb up right. If the float was binding against the burr, the float should still be in the up position inside. So I put my ear to the bowl and slowly loosened up one of the screws. And sure enough, at that moment, I heard the float drop down. So I then smoothed out that burr, and even lightly sanded the small ridge on the float,put it all back together. Looking thru the float level hole on the side, with good light behind me, I genlty moved the carb around, and actually saw the float moving freely!:) Before,the float was down when I put on the bowl, and didnt know it was being held down by that burr, and wasnt moving up to close the valve once gas started flowing. I do not know why it bound now and not before, though. (Maybe new thicker gaskets pushed the metering plate out closer to the float??)
Problems solved? Unfortunatly not.:(
The main reason I did this rebuild was due to gas being slightly puddled on the intake. Thought the gaskets were the problem. Well, after I reinstalled the carb after the latest fix, I undid the coil wire and cranked it a little, just to be sure gas wouldnt shoot out like before. And it didnt!!:D Well, as I just stared at it in relief, I noticed a couple drops come off the secondary throttle shaft:( I now figured thats where my problem always was). I never actually seen it drip prior to all this rebuild mess, but I smelled the gas after I drove and parked the car. Now what? Do I have to buy the whole baseplate assembly? Or are there gaskets or O rings kits for the shafts? Looks like a bitch to tear the base plate apart.
 

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Leaky throttle shafts are a common problem. You could have the baseplate bored and bushed for a tight fit or just replace the baseplate. But, something to consider- at idle there shouldn't be any fuel around the secondry throttle shafts to leak so something else is wrong. Check to make sure your boosters aren't flowing any fuel because the float is still adjusted too high. A float level that is slightly high can also dribble fuel out the boosters after shut down and this will easily leak out the throttle shaft bores. A running engine pulls enough vacume that is rarely leaks out the throttle shaft bores.

Stiff return springs are the main cause of throttle shaft/bore wear, poor throttle cable/lever angles can also cause wear.
 

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Discussion Starter #17
Leaky throttle shafts are a common problem. You could have the baseplate bored and bushed for a tight fit or just replace the baseplate. But, something to consider- at idle there shouldn't be any fuel around the secondry throttle shafts to leak so something else is wrong. Check to make sure your boosters aren't flowing any fuel because the float is still adjusted too high. A float level that is slightly high can also dribble fuel out the boosters after shut down and this will easily leak out the throttle shaft bores. A running engine pulls enough vacume that is rarely leaks out the throttle shaft bores.

Stiff return springs are the main cause of throttle shaft/bore wear, poor throttle cable/lever angles can also cause wear.
I was thinking also that there shouldnt be fuel in the secondaries. You mentioned after shutdown,.I didnt even have it running! I just pulled the coil wire and cranked it first to see if fuel wouldnt shoot out of the vent tube as it did before. But like you said, the floats are lower now, but still too high. There is fuel dribbling out of the sencondary boosters, and Im hoping that is why the shaft is getting wet. But it isnt coming out the vent tube:)
Also I earlier mentioned a link to how I reset the levels, but tonight I learned something new. I thought floats were either made of brass, or nitrophyl, which I thought mine were since they weren't brass. I didnt know there were plastic ones too, which mine must be because they arent black. They are a dull orange color. And I found out that plastic have a totally different dry float settings compared to nitrophyl. So I'll retry it all again. Its great being a novice at this.:rolleyes:
 

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You need to lower the float settings well below where they need to be, then start the engine and with the engine running adjust them up so the fuel is just below the site plug hole. Crack the screw loose just a little and turn the hex nut counter clockwise to raise the float level. Once you get the float levels set then move on to adjusting your idle mixture.
 

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hey terryt

hey terry i think all of us have been in your shoes right know it is sorta frustrating when you put something together and it still leaks just think you saved some money by not letting someone else rebuild it or buying a new carb. look what your learning right know all the info these guys are giving you and its free just think when you get it all dialed in its going to work good :yes: :D try not to let your frustrations take over just relax and have some cold ones to calm down and then start over again. the throttle shafts on holleys are known for leaking ( even out of the box brand new ) it happens yeah they shouldnt but they do. your type of carb i always had problems with but they work great ive rebuilt a couple for some friends and they seem to work fine. the shaft does have a bushing and it wears down after a while its teflon. you can also convert your carb to a 4150 with kit # 34-6
 
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