Venturi
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Re: Venturi
Well I do know the first thing you need to do is remove the bowl nut, spring then emulsion tube completely then with something soft like plastic or a wooden dowel lightly tap it out from the throttle side. I'm sure Cotten will have the best method.
Jim
Jim
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Re: Venturi
Whitey!
It didn't fall apart?
Then I s'pose Jim has the jist of it, with gentle heat from a heatlamp and a lot of penentrant. Removing the main nozzle (emulsion tube) can often be the greater issue. The search function should take you to previous discussions on means of pulling it safely.
And they seem to run pretty good with the venturi in backwards, when everything else is in order. Backwards throttlediscs are not uncommon either.
...Cotten
It didn't fall apart?
Then I s'pose Jim has the jist of it, with gentle heat from a heatlamp and a lot of penentrant. Removing the main nozzle (emulsion tube) can often be the greater issue. The search function should take you to previous discussions on means of pulling it safely.
And they seem to run pretty good with the venturi in backwards, when everything else is in order. Backwards throttlediscs are not uncommon either.
...Cotten
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Re: Venturi
Forgot to mention it's also upside down, the main nozzle couldn't even have been installed, the venturi is blocking the hole, thanks for the info. I'm going out now to see if I can tap it out
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Re: Venturi
Clean the bore with some Scotchbrite, get a 1" or 1-1/8" (depending on what size carb it is) socket and extension, hose it down with PB or Kroil and gently tap it with a wubba hammer and see if it moves, if not keep hosing and keep tapping. It will come out......
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Re: Venturi
You never know what you'll find, Folks:
...Cotten
or even;
But still, those that seem resonably serviceable after moderate ease of removal, invariably deserve more attention....Cotten
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Re: Venturi
Removed it with a 1 9/16" piece of Delron I turned, it tapped out fairly easy, I cleaned it and it slid in pretty easy, was wondering what keeps it from shifting around other then the main nozzle ???
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Re: Venturi
Ideally they are a light press fit and fully seal against the carb body. They can be GENTLY swaged to fit snugly. It has been covered here extensively and Cotten has shown pics of his techniques. All is in the Knowledge base and available for review.
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Re: Venturi
White1j0!
Its mostly about daylight around the outside, after you thorougly clean both venturi and bore. You hope it doesn't rattle upon the nozzle spigot of course. Just like the airleak around the outside, any wear at that point defeats the 'accelerator sump' action of the nozzle.
Even when I swage potmetal venturies far oversize, and then cut to a light press fit, it may only be a matter of a few months that it has returned to a slip-fit, however they retain their round-ness, and 'daylight' is still scarce.
You want the throttledisc to close just as sweetly, with the idle screw relieved.
And actually, I haven't posted much about my swageing methods at all.
If you don't have a lathe, please don't try.
....Cotten
Its mostly about daylight around the outside, after you thorougly clean both venturi and bore. You hope it doesn't rattle upon the nozzle spigot of course. Just like the airleak around the outside, any wear at that point defeats the 'accelerator sump' action of the nozzle.
Even when I swage potmetal venturies far oversize, and then cut to a light press fit, it may only be a matter of a few months that it has returned to a slip-fit, however they retain their round-ness, and 'daylight' is still scarce.
You want the throttledisc to close just as sweetly, with the idle screw relieved.
And actually, I haven't posted much about my swageing methods at all.
If you don't have a lathe, please don't try.
....Cotten
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Re: Venturi
Cotton, did you ever think of cutting, on the lathe, a small recess in the heftier portion of the venturi and installing a thin "O" ring?
For fit and sealing properties.
Jim
For fit and sealing properties.
Jim
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Re: Venturi
Jim!
I did for a minute.
Too many un-necessary machine set-ups, all beyond the initial swage-and-recut.
Please note that the critical region for seal is to the rear, where it is not hefty, but quite thin.
A leak at the front would only add to the main nozzle draw, if at all required.
And why add food for P4gas to digest?
Even if a uniquely-thin viton is available, its in bulk.
Where would my customers find one a decade from now?
Keeping to the original design as close as possible keeps it simple.
...Cotten
I did for a minute.
Too many un-necessary machine set-ups, all beyond the initial swage-and-recut.
Please note that the critical region for seal is to the rear, where it is not hefty, but quite thin.
A leak at the front would only add to the main nozzle draw, if at all required.
And why add food for P4gas to digest?
Even if a uniquely-thin viton is available, its in bulk.
Where would my customers find one a decade from now?
Keeping to the original design as close as possible keeps it simple.
...Cotten
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Re: Venturi
cotten,
if you ever decided to experiment harbor freight has viton in a 180 pc assortment for 11 bucks. http://www.harborfreight.com/180-piece- ... 67525.html" onclick="window.open(this.href);return false;
i have a couple from this kit installed in petcocks to see if they hold up. i think the kit goes big enough to cover some manifold applications as well.
john
if you ever decided to experiment harbor freight has viton in a 180 pc assortment for 11 bucks. http://www.harborfreight.com/180-piece- ... 67525.html" onclick="window.open(this.href);return false;
i have a couple from this kit installed in petcocks to see if they hold up. i think the kit goes big enough to cover some manifold applications as well.
john
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Re: Venturi
John!
A kit is on my Christmas list, but not for sealing venturies.
Not enough meat to seat it in, no reason to go to extra machine steps beyond what already works, and no reason to add variables for the future.
Simplicity is what made these carbs miraculous.
....Cotten
A kit is on my Christmas list, but not for sealing venturies.
Not enough meat to seat it in, no reason to go to extra machine steps beyond what already works, and no reason to add variables for the future.
Simplicity is what made these carbs miraculous.
....Cotten