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Carb leaking HS2 at bottom of float chamber

BugeyeNJ58

Jedi Hopeful
Offline
1275 engine in 59 BE. HS2 carbs. Driving car and noticed smoke coming into car. Stopped and saw that the rear carb (nearest firewall) was dripping gas onto exhaust pipe.

Checked it out and saw that gas is dripping at the bottom of the float chamber where the screw tightens into the float chamber. This is the screw that attaches the flow pipe from the float chamber that continues into the jet in the carb itself.

I made sure it was tight, but when I tap the hose where it attaches, small amount of gas leaks. Looked at an extra set of carbs I have and when I unscrewed that nut totally, say that there is a very small rubber grommer that sits in the screw tunnel that the flow pipe goes into.

Do you think this is what could be leaking? Can this part be purchsed? I'd rather buy one new than use another 20 year old part. Any other ideas?

Thanks...
 
I was told about two years ago that that o ring was not availavle. I have had no reason to search further. I can not immigian that it is not made somewhere.
 
They are avalible from VB. I'm about to order some myself.

pt# 3-991 seal $1.95 ea
pt# 3-990 washer $.85 ea


Get some bowl gaskets too while you're at it. It's always nice to have spares.

pt# 3-569 IIRC. It's not in my notes. Check the site to be sure. $1.95 or something each.
 
Thanks all! I'll order some and use the "new" old one while i'm waiting.
 
Or,
If in the area you live you have a pneumatics supply house a 2-008 (dash number) Buna or viton o-ring will give you the correct OD, ID size to seal it.
Make sure the small metal washer is still behind the rubber seal is there in place.
Be careful not to over tighten the brass nut it's easy to cut the seal.



Dug
 
Spritenut,
I like the 2-008 (#8??) as it’s closer to the size of the area it fits. #7 will work no question as it's a 5/32” ID with a 9/32" OD so once the 5/32” is stretched over the 3/16” tube the OD is likely to be closer to 5/16” and it's less than a 5% installed stretch.
The 2-008 is 3/16” ID x 5/16” OD. Both the ID and OD have a 15-20% compression factor added to the actual physical size for sealing.
I wonder if the dash sizes match the # designations at hardware stores?

Dug
Both will work for sure
 
Dug said:
Or,

Make sure the small metal washer is still behind the rubber seal is there in place.
Be careful not to over tighten the brass nut it's easy to cut the seal.



Dug

You meant in front of the seal b/w the seal and nut, right?
 
It's call a gland (it has square face unlike a o-ring), and it also takes a small brass washer with it, most hardware store fixes will just end up leaking again, I get these parts from Joe Curto, they are cheap enough to have some spare lying around, www.joecurto.com The good thing about dealing with Joe, is, isn't just sombody taking a parts order, he rebuilt more SU carbs than most of us have ever seen, so you get good tech advioce as well from a seasoned expert, the big two just have warm bodies asnwering the phone.
 
While the seals do appear to be available, the last time I needed one, I needed it in a hurry so I made my own. You can too.

Buy a short length of 3/16" ID fuel hose. Use a razor blade to cut off a nice square slice about 1/8" wide. Now take the razor blade and cut gently through the outer rubber jacket of your 1/8" thick donut. Stop when you reach the fibers between the inner and outer layers of the hose material. Peel off the outer later and the fibers. You now have a square cut gland seal made from material compatible with fuel. My emergency fix has been installed for 5 years now without issue.
 
Kellysguy,

Yes I do, my typed message didn't read well.

Since I tend to look at placing the nut onto the tube first, then the washer, and lastly the o-ring, I see it from that view. Given that view, the washer is behind the o-ring.

Yet another way would have been to say, make sure that the assembly for sealing the jet tube has the small washer located between the nut and o-ring during re-assembly.

If I were better at keeping clarity in information, I might have included something about, by leaving approx 1/8” to 5/32” of the tube protruding from the face of the o-ring and carefully inserting the assembly into the float bowel. I feel the chance the o-ring won’t interfere with the jet tube fully seating into it's locating face in the float bowel or the o-ring slipping to the very end of the tube before the nut can be tightened, gives a better chance for it successfully sealing while trying to hold onto a plastic tube covered by a spring.

There is very little pressure here and gas will take the path of least resistance. The rubber seal, be it round or square, is to provide a compressed seal to the jet tubes OD and the ID of area in the float bowel.

The proper square rubber seal is far better than an o-ring because of its thickness and how it compresses by design, but assembled correctly an o-ring that can be acquired from a local source is a good safe fix.

Dug

Doug, Nicely said. That is a great ideal!
 
There is a piece of brass tubing at the end of the plastic tube, stuck inside the plastic fule line, it job is to flare under compression agaisnt the gland and copper/brass washer, that what creates the seal. If all this is fubar on your set up, then the best thing to do is buy a new jet. Again, I cannot say enough about buying carb parts from Joe Curto, most of these parts he makes himself, so you getting parts made for SU, by a man who builds SUs, something to said for that.

There was a guy in my car club, he had been been using o-rings for years to seal this area, and stood up and talked about it at club meeting one night, after the meeting I told him he needed to get the correct parts, and to call Joe Curto, which he had never heard of. Needless to say after years fo dealing with this issue, he got the right parts from Curto, and has not seen a leak since, he wrote a big article about it in the club newsletter.

I'll be honest I find these types of threads sorta humorous, people are always looking for hardware store fixes, sometimes they work, sometimes you need them to just get home, but for the most part these half cocked methods fail miserably in a short time, so the most efficent and least expensive route to take is get the right part and fix it once. Ok so you pay 5-10 bucks to get the right parts to you, when that that hardware store o-ring is only 15 cents, but the right part is cheaper than your car burning to the ground. My mind just doesn't revolve in the hardware/NAPA store mentality, I'm lazy :smile:, I only want to do the repair once. This is why I'm a bench builder and not a LBC mechanic, I got tired of that real quick, you see some nice well taken care of cars, but for the most part you see cars that have been jerry-rigged from one end to the other , and if I had to deal with that on daily basis, they'd have come take me away to the rubber room :smile:
 
Hap said:
This is why I'm a bench builder and not a LBC mechanic, I got tired of that real quick, you see some nice well taken care of cars, <span style="font-style: italic"><span style="font-weight: bold">but for the most part you see cars that have been jerry-rigged from one end to the other</span></span>, and if I had to deal with that on daily basis, they'd have come take me away to the rubber room :smile:

Yup. And to try and explain to a proud new owner of an LBC that has been compromised just why they should spend MORE money to correct said rigging can be as hair-pulling a task as actually FIXING the car. :wall:
 
DrEntropy said:
Hap said:
This is why I'm a bench builder and not a LBC mechanic, I got tired of that real quick, you see some nice well taken care of cars, <span style="font-style: italic"><span style="font-weight: bold">but for the most part you see cars that have been jerry-rigged from one end to the other</span></span>, and if I had to deal with that on daily basis, they'd have come take me away to the rubber room :smile:

Yup. And to try and explain to a proud new owner of an LBC that has been compromised just why they should spend MORE money to correct said rigging can be as hair-pulling a task as actually FIXING the car. :wall:

Yep, we just saw a big case of this recently, a nicely, newly restored Bugeye, and it looked great, a local guy had restored it. He spent enourmous amounts of time detailing this and that, but not alot of time worrying with mechanics, needless to say the new owner spent about $4K with my buddy at his shop before the car was road worthy. The funniest one was how the guy had took the time to paint and detail a worn out brake master cylinder, then there was the front suspension, the spindles, steeering arm were painted bright red red and the control arm a nice silver, but the king pin bushing were so woprn out you could literally jiggle the front suspension, makes you wonder about people some time. Truely sad for the new owner.

Then there was the guy who posted here one time, bought a Bugeye project from my buddy, the word that had been passed down the line was, it had a rebuilt engine, but who really knows. The new owner took the car down to bare metal, did a really nice restoration, but never even inspected the inside of the motor, you're kidding right :smile: Anyway it had a rod knock when he cranked it, he took it to a show as non running car, won first in the Sprite class and we never heard from him again, why would anyone go to that much trouble and not pull a oil pan, that just amazes me.
 
Hap Waldrop said:

why would anyone go to that much trouble and not pull a oil pan, that just amazes me.

Because they don't feel comfortible with their abailties to do so. They can paint well, thus they do.

Think about it Hap, most paint ond body guy's cars run like crap but look great and the techs drive well running pieces of junk.
 
We all have to learn, ignoring the problem won't make it go away. Take Jack for example, the whole restoration of his car was learning exercise, but he ask a million questions, and went thru it all, sure he had to go back and do a few things but he stayed after it, and got it done, well as done as one of these cars can ever be :smile:

Here's the way I look at it, if we want to learn, we will learn.
 
The original clear plastic hose, with spring and gland nut assembly is fine, but sometimes its the hose that splits and is at fault. I worked for the manufacturer of these things for a while, and we had problems, and I'm not so sure I trust the plastic's compatibility with modern fuels.

Might I suggest a different jet? Offered by some aftermarket vendors, made by Royze inc in CA. Part number 159-008a. Has a tapered plastic tread-in nipple for the bowl end, and a jet with nipple. In between goes some VW style fabric fuel hose that is superior to the current lot of fuels. No more gland nut and washers, just a nice tapered fitting that conforms to the bowl threads. I've sold many to happy people, including myself.

Peter C.
 
I am one of Peter's happy customers with more than couple of these carb kits.
Top notch modern version that can be fixed if needed some 50 years from now with nothing more than another piece of hose.
Much better than the original set up.
 
That might be an option forme as I had to lenthen my hose due to moving the rear bowl back. How much are these kits you speak of in American dollars? This would be for the Spit/Midget 1500 euro carbs.
 
PeterC said:
The original clear plastic hose, with spring and gland nut assembly is fine, but sometimes its the hose that splits and is at fault. I worked for the manufacturer of these things for a while, and we had problems, and I'm not so sure I trust the plastic's compatibility with modern fuels.

Might I suggest a different jet? Offered by some aftermarket vendors, made by Royze inc in CA. Part number 159-008a. Has a tapered plastic tread-in nipple for the bowl end, and a jet with nipple. In between goes some VW style fabric fuel hose that is superior to the current lot of fuels. No more gland nut and washers, just a nice tapered fitting that conforms to the bowl threads. I've sold many to happy people, including myself.

Peter C.

I agree!!!!!

Fuel injection hose works. And doesn't cost too much.

Steve
 
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