A real DLX-113?

[Snakeoil]

Thanks for the quick reply. I was a machinist in a former life so I understand your points well. Although I must admit that I did not know you could TIG weld Zamac, which is what I believe this are made from.

I have spoken to a gent that makes new floats from modern milspec materials that are not affected by today's fuels. Although that could very well be what is already in the carb since the bike was restored about 6 years ago. Guess I'll find out when I take it apart to stop the drooling. Like that term better than overflow. Fits the age of the bike. Fire is a scary thought and my first when I noticed onto what the fuel was drooling that first day. No battery in the bike at the time.

Thanks again.

regards,
Rob

[T. Cotten]

Rob!

The term "Zamac" is new to me, and I hope to get upon modern PC to google it soon, thanks!
Most of us call it 'die-cast zinc' at best, or at worst: "potmetal", as it seems to be the dross off the top of the pot.

My most skilled TIGmeisters can handle the later models, but anything in the 80 series seems to explode.

Many are cutting the latest float material.
Few however, have determined the proper proportions with the ultralight foam to deliver the same buoyancy as the original corks.
Folks should beware of molded elliptical floats that weigh three times as much (shown on the left-side scale pan in the attachment).
Originals average close to 3 g.
Beware also, that the potmetal models used a different size than the bronze bowls.

....Cotten

[Rubone]

Zamak was a brand name of die-cast zinc. It was in common usage when the technique was new. In the UK it is Mazak...

[Snakeoil]

More good points. Has the actual fuel level in the bowl been determined for needle valve closed position? I'm trying to think of a way to deal with floats of varying weights.

But then again, I suppose you could simply drill the foam floats and add lead shot and phenolic epoxy to match the weight of the original floats. That type of epoxy is not bothered by today's gasoline. Probably only take a few minutes to have a foam float weighing the same as an original, assuming the displacement is the same. I have a precision digital reloading scale and can measure weight down to a gnat's whisker. Still have the brass floats in my vintage Hondas and when I repair them I always weigh them to assure they are not loaded with solder.

Irv Truax referred me to the gent with the floats. His name is Ed Glasgow. I think Irv mentioned your name at the same time. I say that because your name is in parentheses next to Ed's name in my notes. Ed is near our camp so I'll probably drive over to see him. Might bring the bike to camp and play with it there.

regards,
Rob

[T. Cotten]

Rob!

Let me first interject to "never say never" when it comes to fuels attacking epoxies and other compounds, because you never know what will come out of the Nation's pumps with the next "summer blend".

And Ed Glasgow is as trustworthy as they get!

On to float levels,
I have yet to receive any authentic literature for late-'29 to '39 models, and would be sincerely greatfull if some should surface;
In the meantime, I have been damn lucky.

....Cotten

[Snakeoil]

Got into the carb today. Looks like the drooling was from old gaskets, a loose float and somewhat distorted sheetmetal cover.

Sorted out the cover issue. Talked to Jim Walther who makes the thread repair for these carbs and he said they leak because of that tin top not fitting well. Since my gaskets were bad, I decided to cut new ones from 0.030 material and stack them up to give me room to put a gasket on top of the tin cover. Got that sorted out and just before putting it back together, noticed the float was loose on the arm and when I went to tighten it, my screwdriver slipped and I broke the float. It was one of the new foam floats, I assume from Ed Glasgow. So left a message for Ed to send me a new float. That was a $50 slip of the screwdriver. I might be able to repair it with gasoline proof epoxy.

I think my gasket on top will stop the drooling. Unfortunately, I won't be able to tell you until I have a float in place.

I did blow out the fuel lines while I was at it. Nasty stuff in there. 7 year old gas in those lines. Smelled like an the floatbowl on an old outboard.

regards,
Rob

[T. Cotten]

Rob!

Just for clarity, Jim Walther did not make the thread repair shown in my previous photo.

Beware with your new float that it too, will be quite brittle.

Is the carb bore still round?

....Cotten

[Snakeoil]

Thanks Tom. Do you make those floats that Ed sells? I see he has TC as a code next to them and on the phone mentioned your name. I tried to find contact info for you, but struck out. Ed has one in the mail to me. I also repaired my crack with an epoxy I know is okay with today's fuel. I tested it, and made another blob to test again.

I actually weighed the float before repairing to see how much more it would weigh with the repair. It weighed 37.7 grains before the repair. This morning I weighed it with the epoxy hardened and it weighed 34.4 grains. At first I thought my scale went nuts. But then I thought that the float may have absorbed some fuel. So I set it in the sun for a few hours and weighed it again. This time 34.3 grains. So, they apparenty do aborb a slight amount of fuel.

Repair is strong, probably stronger than the foam. But I'll keep it as a spare.

Is my bore round? I'd have to say yes. Carb actually looks quite nice. I'll snap a few pics of the carb and post here. If there is anything special you would like to see, let me know. They're pretty simple. Reminds me of a RC engine carb only much bigger.

regards,
Rob

[T. Cotten]

Rob!

Yes, I machine DURABLE floats for Ed.

There are many fine epoxies on the market, however fuels are the problem, and changing constantly. The last couple of seasons of my local Shell P4gas degraded fresh JBWeld in tests, although samples that were cured beyond six weeks still survived quite well.
So please allow any goober to sit for a long time before exposure.

If the float you weighed has a porous surface from machining, (such as my DURABLEs), then you can expect some fuel to reside in the outer layer of closed cells that have been cut open. But as you found, at 20 milligrams, it would be minimal.

Have you put a dial indicator in the bore?
After cleaning the venturi, is there daylight around it?

....Cotten

[Snakeoil]

Tom,

Keep in mind that this bike is brand new to me and these ancient carbs are also a totally new experience as well. Until the Indian, my oldest carb was an Amal Monobloc.

Here are some pics I just snapped of the carb, which is mounted on the bike. This engine was rebuilt by Irv Truax. He actually did it twice, once as a full rebuild and then again as a check since it sat for almost 10 years after he rebuilt it without ever running. He said he runs them on a test stand before he gives them back. So I assume Irv went thru the carb, although I never asked him that specific question when we spoke. I plan on going out to see him and buy him lunch so I can pick his brain a bit. He was really helpful over the phone the one time we did speak, which was just before Sandy hit and he was prepping for the worst.

Pics of the carb.








Regarding epoxies, I have already tested JB weld and although it does not dissolve, it gets soft when immersed in either E10 or pure ethanol. When you take the sample out, it rehardens. It gets rubbery, but not gooey.

I normally test expoxies for the effects of fuel for at least 30 days in sealed containers. The epoxy I used to repair the float was tested a couple of years ago and had zero effect from fuel. I will however test a new sample that is now hard and will report back in 30 days. My experience is if it is going to be affected, it will happen within 2 weeks. Of all the various products I've tested, those affected showed worst case within 2 weeks and a further two weeks in the fuel had no further effect.

regards,
Rob

[T. Cotten]

Rob!

Your bowlnut threads look pretty decent!

I really cannot judge a carb from photos,
but the "smile" on both sides of the nozzle vent is an indicator that the venturi needs to be re-sized, as virtually every one does.

Fuel-proof black enamels are getting rare or extinct, so I don't blame Mr. Truax for skipping it.
The problem hounds me constantly.

Some years ago, I tested JBWeld along with other sealers and paints in 95% ETOH 5% H20, and it was unaffected, as were other products proven to suffer in ethanol fuels.

Its not just the ethanol.
Its the combination of many additives that give fuels their digestivity.
And you never know what's going to be in next season's summer blends.

JBWeld survived well through years of extremely digestive fuels, however, for the last two seasons, fresh JBWeld has shown the sort of degradation you mention in my tests.
Seasoned JBWeld was unaffected.

Folks, USA fuels are not nearly as bad as they were, inspite of ethanol, for now... .. .

....Cotten

[Snakeoil]

When I first peered into that carb I thought that the "smile" around the venturi was odd. When you say "resize" the venturi, are you talking a repair to the existing piece or machining a new one from scratch with different dimensions?

You asked if my bore was round. Judging by the clearance seen in that throat, I assume that over time, these castings go oval due to creep. Is the fix to bore them round and then fit a new venturi?

I wonder if POR 15 paint would hold up to the modern fuels? Or how about the paints they make for RC models. They claim those paints are fuel proof and that includes nitro, which would probably eat most other paints.

There is some what looks like original paint remaining on the side with the markings and the tin top has paint on it, but not much.

regards,
Rob

[T. Cotten]

Rob!

Usually I swage the original venturi oversize, and then cut it precise for the new body bore size, although not all original venturies survive extraction, much less the swage process.

My luck with POR-15 has been only to test my local fuel, as it is one of the first samples to degrade, even in the mildest of years.
And Aerogloss does little better than my choice of VHT epoxy for paint, which is far from adequate.

Please remember that many great products are truly gasoline-proof.
But other stuff comes out of the pumps!

....Cotten

[Snakeoil]

Thanks Tom. You have me convinced that it is more than just an ethanol thing.

I'm curious, are the venturis pressed into the carb body or does the nozzle hold it in place? I suppose the separate venturi was so that one carb body would fit multiple size applications by just changing the venturi in final assembly.

I thought I knew the answer to this next question, but now I'm not so sure. There is a small cutout on the ID of the sheetmetal top. It looks like a locating notch. There is no mating male lug on the bottom of the carb bowl flange. There is what appears to be a casting seam and it does seem to line up with the cutout when the top aligns with my fuel line. But the lug is so shallow that is really seems of little value. Should there be a heavier lug to engage that cutout or perhaps a pin pressed into the bowl flange? The gaskets for the top of the bowl have the same cutout, yet are on the bottom of the sheetmetal top so will never see that casting seam/lug. Is something missing from my carb body?


regards,
Rob

[T. Cotten]

Rob!

The venturi would ideally be a slip-fit, with no daylight around it, at the rear anyway.
But venturies suffer from distortion over time, even more than die-cast bodies, and even Linkerts are far from immune.
By nature, the potmetal moves, like old window glass.

Venturies tend to shrink on the OD, and expand on the ID.
Nobody cares if the ID increases.

My procedure has been to install them as tight as possible.
In just a year or so upon the shelf, they can become slip-fits!

On to the cover detente, the larger carbs had a nub that located the cover onto the body, presumeably for gasline alignment, but it is missing on the 1" Four carbs, and maybe others if I look...

....Cotten