Weber Carb Floats, How to check/adjust them? |
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Weber Carb Floats, How to check/adjust them? |
Lawrence |
Jul 22 2003, 04:38 PM
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#1
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Senior Member Group: Benefactors Posts: 1,661 Joined: 5-February 03 Member No.: 244 Region Association: None |
I've looked at the Weber Service Manual kindly scanned for us.
Can the check/adjustment be done without the special tools listed in the manual? If so, how? -Rusty (IMG:style_emoticons/default/smoke.gif) |
ein 6er |
Jul 22 2003, 06:19 PM
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#2
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Senior Member Group: Benefactors Posts: 1,115 Joined: 11-February 03 Member No.: 300 Region Association: None |
yes
i have the haynes weber manual and it says to use a rubber wedge to hold the float and venier calipers and a feeler gauge for the mesuarments. that's how i dunit. doug |
Lawrence |
Jul 22 2003, 06:29 PM
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#3
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Senior Member Group: Benefactors Posts: 1,661 Joined: 5-February 03 Member No.: 244 Region Association: None |
Was the adjustment fairly easy?
Do you know about how to check the floats for servicability? I'm concerned about reasons why my carbs might be overflowing. Checking the needle valves are next on the list. I cleaned them once before.. but I'm going to check them after the floats. -Rusty (IMG:style_emoticons/default/smoke.gif) |
ein 6er |
Jul 22 2003, 06:46 PM
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#4
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Senior Member Group: Benefactors Posts: 1,115 Joined: 11-February 03 Member No.: 300 Region Association: None |
did your bowls just start overflowing?
has it been running? how do you know they are overflowing? leaking fuel somewhere? if the floats are leaking, you should be able to shake them and feel the fuel in them. yeah it was easy, a little tedious. you want to check and recheck you measurements. |
Lawrence |
Jul 22 2003, 07:01 PM
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#5
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Senior Member Group: Benefactors Posts: 1,661 Joined: 5-February 03 Member No.: 244 Region Association: None |
Yes, it was running. But, I had a problem of fuel hydrolock of the engine. Now that I've fixed other issues, now I'm looking for the root problem of the hydrolock.
-Rusty (IMG:style_emoticons/default/smoke.gif) |
ein 6er |
Jul 22 2003, 07:15 PM
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#6
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Senior Member Group: Benefactors Posts: 1,115 Joined: 11-February 03 Member No.: 300 Region Association: None |
hhmm .... "i think" .... overflowing bowls can be sticking needle valves, sinking or sticking flaots or too much fuel pressure.
do you know your pressure? if it has been running fine. the float levels are probably good. |
Gint |
Jul 22 2003, 10:48 PM
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#7
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Mike Ginter Group: Admin Posts: 16,071 Joined: 26-December 02 From: Denver CO. Member No.: 20 Region Association: Rocky Mountains |
Dude,
The measurement the manual lists is only approximate. It will get you running, but it won't get the float levels to the correct setting all by itself. BTDT You really need to follow up with the gauge that screws into the sides of the float bowls. Call my cell tomorrow. |
FlatSix |
Jul 23 2003, 05:54 AM
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#8
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English Member Group: Members Posts: 191 Joined: 14-January 03 From: Poole, England Member No.: 144 |
I purchased the float gauge tool.
Using it was a pain. When the engine was running, the float level 'jumped' due to vibration. A lot of fuel is wasted due to having to drain each float chamber to screw it in, and to add washers under the float valve. There also is some 'surface tension' on the fuel so the height is difficult to judge accurately. Mine seem to be about right now (only one needed a washer to raise the valve), but I remain to be convinced about this method. Attached image(s) |
Lawrence |
Jul 23 2003, 06:02 AM
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#9
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Senior Member Group: Benefactors Posts: 1,661 Joined: 5-February 03 Member No.: 244 Region Association: None |
My gut instinct tells me that the issue isn't the float adjustment (it's been running fine for 2-3 years without tampering with it). However, I've got to pull them to check to see if they're leaking inside, so I might as well adjust the height.
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J P Stein |
Jul 23 2003, 11:36 AM
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#10
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Irrelevant old fart Group: Members Posts: 8,797 Joined: 30-December 02 From: Vancouver, WA Member No.: 45 Region Association: None |
I use the gauge in the pic.
I set the floats with the carbs off the engine....static, with the carb in a pan to catch the gas. A few "special tools" were necessary to fill each float bowl......backyard engineering....a turkey baster for one (IMG:style_emoticons/default/wacko.gif) A bit of experimenting with shims under the needle valves to learn how much each effects the float height. Another PITA, but part of the learnng curve. |
Lawrence |
Jul 23 2003, 11:40 AM
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#11
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Senior Member Group: Benefactors Posts: 1,661 Joined: 5-February 03 Member No.: 244 Region Association: None |
Why did you fill the float bowls to set their height?
Anything special about the shims? Something I should buy locally, buy from PMO or make myself? Nothing is ever easy. (IMG:style_emoticons/default/headbang.gif) |
Gint |
Jul 23 2003, 11:52 AM
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#12
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Mike Ginter Group: Admin Posts: 16,071 Joined: 26-December 02 From: Denver CO. Member No.: 20 Region Association: Rocky Mountains |
QUOTE I purchased the float gauge tool. Using it was a pain. When the engine was running, the float level 'jumped' due to vibration. A lot of fuel is wasted due to having to drain each float chamber to screw it in, and to add washers under the float valve. There also is some 'surface tension' on the fuel so the height is difficult to judge accurately. Mine seem to be about right now (only one needed a washer to raise the valve), but I remain to be convinced about this method. While I agree that there is some wasted fuel (I used a catch can), I had no problem using this gauge. And, despite how carefully I measured the floats with a caliper during the rebuild, the gauge told me perfectly well how far off my measurement was. I'm not sure where you can get the shims other than PMO. I'm sure anyone that stocks Weber parts could provide them. Sorry Lawrence, I left the cell phone at home today. |
Lawrence |
Jul 23 2003, 12:36 PM
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#13
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Senior Member Group: Benefactors Posts: 1,661 Joined: 5-February 03 Member No.: 244 Region Association: None |
Hey Mike,
When doing the float level adjustment - why have gas in the carb? -Rusty (IMG:style_emoticons/default/smoke.gif) |
J P Stein |
Jul 23 2003, 01:27 PM
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#14
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Irrelevant old fart Group: Members Posts: 8,797 Joined: 30-December 02 From: Vancouver, WA Member No.: 45 Region Association: None |
The gauge in the pic attaches to the port in the side of the float bowl. It fills with gas. The level of the gas is between the upper 2 lines on the gauge when the floats
are set properly. Using the static method, I set the level at the 2nd line from the top ...Kentucky windage for the lack of pressure...seems to work. Setting the floats is prolly the most important part of dialing in Webers so's they neither flood nor lean out durring hard cornering. Shims come with the rebuild kits....never throw any away.....I have a pee pot full of them in both copper and ....composition. |
ein 6er |
Jul 23 2003, 03:12 PM
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#15
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Senior Member Group: Benefactors Posts: 1,115 Joined: 11-February 03 Member No.: 300 Region Association: None |
ohhh shezzzz ..... yeah, you definitly need the float level gauge!! sorry .... i took a quick glance at the manual you were referring to and i only saw the spring to hold the float and the special gauge for the float.
if you are taking the tops off, you should get the rebuild kits. it's easy to tear the top gasket. plus you get all the shims and other washers. you probably know this, but be careful with those needle valve caps. they are soft and you can muck them up, ask me how i know. it's best to loosen them while the carbs are on the car. but pmo sells new ones. good luck, doug |
sixerdon |
Jul 24 2003, 06:35 AM
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#16
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Member Group: Members Posts: 466 Joined: 23-May 03 From: Dartmouth, MA Member No.: 731 |
Rusty,
Your problem sounds like one I had with over flowing carbs. What you are attempting is what I tried and didn't help until I began to think about the whole system operation. To make a long story short, I loosened the gas cap to allow it to breathe. Clamped off the fuel line to the carbs at the pump. Turned the ignition to on. and listened for all the air bubbles coming back to the tank by way of the return lines. IE; Air block in the return line while the tank is pressurized. The pump is pushing through the line with least resistance. Once the lines between the tank and the pump are fully primed, the pump is rotating the gas between the tank and itself. Try that. Then think about how the entire system works. Worked for me. Don |
Gint |
Jul 24 2003, 07:59 AM
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#17
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Mike Ginter Group: Admin Posts: 16,071 Joined: 26-December 02 From: Denver CO. Member No.: 20 Region Association: Rocky Mountains |
QUOTE Hey Mike, When doing the float level adjustment - why have gas in the carb? -Rusty Well, I suck describing techno-crap, but I'll give it a shot. I'm ABSOLUTELY sure someone will correct me if I'm wrong. The static measurement with a caliper during the rebuild is presumably just to get the floats at a common height relative to one another and in the approximate range required. If done correctly, you would/could end up using basically similar shims for the needle valves in the next step. Using the float gauge and pressurizing the fuel system allows you to shim the needle valves in relation to the floats such that the floats and needle valves working together will shut off the flow of fuel at the appropriate level in the float bowl. So, to my mind, the two seperate measurements are BOTH required in order to get the floats set properly. I suspect you could forgo the caliper measurement. But then you might end up shimming the crap out of the needle valves to compensate. But you can't NOT use the float gauge to set the needle valve height. This is the critical measurement for obvious(?) reasons. Please let me know if this helps or not. I think it's pretty darn close, but WTFDIK? |
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