[goatman65]

Is a brass float a better choice for ethanol laced gas? Rebuilding a carb and not sure if the brass or black plastic,[can't think of the real name],float would be best, or if it really matters.

[Jack Gifford]

I don't know the chemistry. But I haven't seen alcohol harm either brass or plastic floats.

[carbking]

I believe much depends on where you live and the composition of the fuel where you live.

Here in Missouri, we have had the phenolic floats fail in as little as 3 weeks! To prevent this, an EXTRA coating of either POR-15 or model airplane fabric dope PRIOR to submerging the float in fuel.

As to the brass floats, it depends on if you are able to find either new old stock or used ORIGINAL brass floats. These will last for years, even decades; however, we will NOT use the current production offshore reproduction stuff (would really like to use a different word instead of "stuff"!).

Jon

[Tom Vaught]

I have tried to collect the old 2 BBL Brass Floats (when I could find them) but they seem to be long gone in the NAPA stores. As was said, the current production offshore reproduction stuff (nice words Jon) as usual is lacking vs the old OEM parts.

Tom V.

[John Milner]

I personally like brass floats. However, as stated, try to find an original one. The "new" ones you get from Napa look good out of the box but I guess they did not do a good job soldering the seams on these things. I bought 3 new ones for a tripower I restored, got the tripower on the car and fired it up. Ran very nice. I let it sit for a few days and it flooded gas everywhere the next time I tried to start it. I could not understand why it did that. So, I pulled the tops off of the carbs that were leaking fuel and found that two of my floats were filled with gas leaving the needle and seat open. I threw them in the trash and put a couple of original ones back in.

[goat1964-2004]

Originally Posted by John Milner

I personally like brass floats. However, as stated, try to find an original one. The "new" ones you get from Napa look good out of the box but I guess they did not do a good job soldering the seams on these things. I bought 3 new ones for a tripower I restored, got the tripower on the car and fired it up. Ran very nice. I let it sit for a few days and it flooded gas everywhere the next time I tried to start it. I could not understand why it did that. So, I pulled the tops off of the carbs that were leaking fuel and found that two of my floats were filled with gas leaving the needle and seat open. I threw them in the trash and put a couple of original ones back in.

Same thing happened on my 64.

[goatman65]

I can get either float from Napa,the one in the carb now is the black plastic one. I have a handful of older brass floats. Isn't there a way of checking them with hot water?

[carbking]

Submerging a brass float in hot water will reveal any leaks.

The hot water pressurizes the air inside the float and if a leak, it will blow bubbles like an intertube (showing my age ) with a nail.

Jon.

[Doug]

In reviewing the November 1, 1971 Delco service bulletin data (http://www.newagemetal.com/pages/Pon...3-69/index.htm) it appears that the end carbs from 63 thru 65 used the same #7012028 end floats. (No end floats info was listed for 66). The #7012028 float was also used in single carb applications in 63,64,65 and 66 on some 389 and 326 engines.

Apparently float #7000273 was used on the center carbs from 63 thru 66 and the needle valves were the same in all end carbs from 63 thru 66. The center carb needle valves apparently were the same for 63 thru 65 but changed in 66. For single carb applications, the needle valve changed in 1967 and persisted at least thru 69.

With the multi-year use by Pontiac of the same floats, it leads me to ask if the same floats were used in other GM 2GC applications for comparable years and interchangeability of parts. Over the years I have accumulated several 2GC carbs from junk yards and haven’t bothered to try to identify them.

The Delco service bulletin lists for various years 63-69, a carb as “2GC PONTIAC AND TEMPEST V-8's 1 1/2” S.A.E.”. What does the 1 ½” refer to in this designation?

As to testing brass floats by immersion in hot water, remember that the “atmosphere” inside a brass float will expand and build up pressure when it is heated and could possibly create a “rupture” of the float thereby creating a leak. Don’t use really hot water!

[carbking]

Doug - the 1 1/2 S.A.E. is an SAE size 3 carburetor.

This link will help a little. I did the single barrel information years ago, and never got around to doing two barrel and four barrel.

This has to do with flange (mounting) size only, and does not indicate internal (venturi) CFM size.

http://www.thecarburetorshop.com/Car...izesandCFM.htm

The center carb on the 1959~65 tripower is a size 2; the ends, and the 1966 center are size 3.

As to water temp, I let the hot water run until it reaches its maximum (140 degrees F) in my kitchen sink.

Jon.

[Dick Boneske]

Thanks, Jon. I didn't think of using hot water to test floats. Obviously, room temperature water wouldn't expand the air to force bubbles as readily as hot water.

I've had about a half-dozen original floats leak on various Tripowers I've rebuilt. One I've put on the shelf about half full of gas has evaporated very little for the three years it's been sitting. Other than feeling and hearing the gas in the float, shaking it does not produce any drops of gas indicating a leak. The hot water is a better idea.

[carbking]

Dick - even those with defects may be repaired. Below is an excerpt from my website:

"Many mechanics have been conditioned to ask for a float each time they rebuild a carburetor, due to the reasonable price of modern, mass-produced floats, and the propensity of nitrophyl (foam) floats to absorb gasoline after time. In dealing with older, NON-CURRENT-PRODUCTION brass floats, neither of the above are true, and a mechanic should attempt to 'save' the float if at all possible.

The first step is to clean the float and inspect it for obvious damage. Small dings and dents are quite common, even in unused floats, and occurred when the manufacturer shipped the floats in bulk. Major dents (generally caused by water freezing in the carburetor) are not generally repairable. If one can hear liquid sloshing around inside the float, skip to the next paragraph. If the float looks to be reasonably damage-free, it should be tested. Testing is accomplished by grasping the float arm with a pair of needle-nose pliers, and submerging the float in very hot water. The hot water will pressurize the air inside the float, and a leaky float will blow a stream of bubbles.

If the float should need repair, it is important to understand how the float was originally produced. Virtually all brass float pontoons (the floating part) are composed of two pieces (a few are more) of brass soldered together. The pieces differ in the seam area, as one piece has a male seam and the other a female seam. One float piece will also have a small hole for temperature equilization. This hole will be covered by a small drop of solder, and will be as far from the seam as possible. The manufacturer would solder the two pieces together, allow the float to cool completely, AND THEN close the equilization hole. Soldering MUST be done using a soldering 'iron'. Repair should not be attempted using either a torch, or a soldering gun. If you plan on disregarding this advice, read the next paragraph first! The following procedure works for us (no, we will not repair your float unless we restore the entire carburetor): First, if liquid is present inside the float, find the hole, and remove the liquid by placing the hole down inside the hot water. The pressure will force the liquid from the float. If the float has much liquid, it may be necessary to remove the float from the hot water, allow the float to cool, and repeat the hot water dip. Once the liquid has been removed, and the leak has been marked, open the equilization hole by removing the solder. Solder the leak closed using as little solder as possible. A small piece of tape over the equilization hole will allow the hot water test to be preformed. If there are no leaks, remove the tape, and ALLOW THE FLOAT TO COOL COMPLETELY before closing the equilization hole. A final test, and you have 'saved' a valuable float."

Jon.

[carbking]

The absolute key to repairing the floats as above is in the use of the soldering iron.

IF YOU CANNOT HOLD THE FLOAT IN YOUR FINGERS WITHOUT BURNING YOUR FINGERS, YOU ARE NOT USING ENOUGH HEAT!

Jon

[carbking]

One final comment about brass floats:

Rochester did NOT make theirs; the floats were subcontracted by a couple of American companies. We have, in the past, had new floats for other applications reproduced to O.E. specifications, made in the USA! We had to pay up front for the refurbishing of the dies, and the minimum order was ONE THOUSAND PIECES, PAID FOR IN ADVANCE! And the wholesale cost would be more than the retail price of the offshore junk!

At my age, I am not going to fight the "why are you so high, I can buy them much cheaper" attitudes of a lot of enthusiasts. But if some company thought the market existed, it could be done. For the tripower, as already mentioned, one would need to do two different floats.

We had floats with industrial applications reproduced, and it still took many years to sell them.

Jon.

[Pontiac62]

I recently went through all my junk carburetors and found only one brass float for end carbs. Is it worth replacing only one end carb float when the other will still be the plastic type?
thanks,
Les

[indymanjoe]

would a brass float from a 72 2bbl Be of use to anyone here? I think i saved one? it came off a running car.

[indymanjoe]

Originally Posted by Pontiac62

I recently went through all my junk carburetors and found only one brass float for end carbs. Is it worth replacing only one end carb float when the other will still be the plastic type?
thanks,
Les

I wouldn't change anything till it needed it.

[mgarblik]

I really like the hot water test for the brass floats and I learned something new today. If the off shore crap is the only new stuff available, would the hot water test on a new set of these be enough to feel good about using them? Or does it take a few weeks/months for the off shore stuff to begin filling up with fuel? Would love to have new USA sourced floats but I understand the frustration and up front cost to make it happen. I for 1 would gladly pay 2-3 times as much for a USA float that doesn't potentially flood over, catch on fire, and destroy a 50K vehicle. I would call that cheap insurance.

[Pontiac62]

Originally Posted by Doug

In reviewing the November 1, 1971 Delco service bulletin data (http://www.newagemetal.com/pages/Pon...3-69/index.htm) it appears that the end carbs from 63 thru 65 used the same #7012028 end floats. (No end floats info was listed for 66). The #7012028 float was also used in single carb applications in 63,64,65 and 66 on some 389 and 326 engines.

Apparently float #7000273 was used on the center carbs from 63 thru 66 and the needle valves were the same in all end carbs from 63 thru 66. The center carb needle valves apparently were the same for 63 thru 65 but changed in 66. For single carb applications, the needle valve changed in 1967 and persisted at least thru 69.

You only mentioned 63-65. Don't 59-62 us the same floats?

[Dick Boneske]

"You only mentioned 63-65. Don't 59-62 us the same floats?"

I think so. Why would the early large 2G's be different from later ones? In any case, they look the same and function the same.