ckowner

Carter drt-08 carb help

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At present I have a Tillotsen carb on my 1930 DeSoto CK6. (Temporary measure)and it leaks on the exhaust pipe. I have accumulated several DRT-08 carbs, all not in the best of shape. Have derusted them with the washing soda/battery charger method. I have 1 with a stand pipe which is intact. The other two are broken. My information is that this stand pipe screws into the cast housing. After derusting and lots of penetrating oil, I still cannot get the small pieces to unthread from the cast. What is the secret, or does someone have a semi working DRT-08 with a long pump that may only need a basic kit that is for sale? I'm getting so close to getting things together, and now another hiccup. Is there anybody that can help?

Rick VanOene

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The zinc alloy used on the DRT-08 standpipes was the early alloy with much more lead than more modern alloy. Over time, this alloy tends to "grow".

Even with the original standpipe tool (useful for installing a new standpipe), one has a 99.9999999999999999999999999 percent probability of breaking the original standpipe when removing.

The secret: break out the original (the choker cone probably won't slide on it anyway); remove all traces of the zinc alloy from the casting by cleaning in hot caustic lye (CAUTION - THIS SHOULD BE DONE BY SOMEONE WITH THE PROPER SAFETY EQUIPMENT!!!!! THE ZINC ALLOY WILL GIVE OFF TOXIC FUMES WHEN DIPPED IN THE HOT CAUSTIC LYE!!!!!), and then install a new standpipe.

And if you should remove an original standpipe intact: place it on the table and immediately head for Las Vegas; you are ready to break the bank!

Jon.

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Thanks for the valuable information Jon. I thought that I was the problem! After reading extensively about caustic soda, I understand that the only metal it will not attack is the steel housing itself. Will brass parts hold out long enough for the zinc to dissolve. I have been able to remove the long accelerator pump (a cast one), the other carb has a brass one. I imagine that with some care it should unscrew from the housing without incident, or is there a brass pin that locks the thread and prevents the pump housing from turning? I will proceed with caution. Do you sell parts for these carbs? I do have a basic rebuild kit as well as a good bowl. Would need a standpipe and matching cone (smaller version)

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The carburetor should be completely disassembled (other than press-in parts) prior to using the caustic.

The pumps simply unscrew, but the zinc alloy ones often snap when one attempts to remove them.

Do we sell parts? If we have them.

I realize you stated you have the one with the long pump, but that doesn't help identify your carburetor (there are at least 2 different long pumps, and at least 4 different short ones).

In fact, Carter made 42 DIFFERENT versions of the DRT-08. We have original prints and parts for most of them. The item that seems to be almost unique to a specific carburetor on these is the main discharge nozzle. If you look at the "head" end of the main discharge nozzle, there will be two numbers. The first is a 12 (meaning main discharge nozzle) and the second identifies which main discharge nozzle. Armed with that number I can consult my interchangeable parts list, and hopefully determine exactly which DRT-08 you have. With this information, I can then look up the bill of material and see if we have the parts you need. We have maybe 40 or so different standpipes, and 10 or so different choker cones.

Jon.

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The carburetor should be completely disassembled (other than press-in parts) prior to using the caustic.

The pumps simply unscrew, but the zinc alloy ones often snap when one attempts to remove them.

Do we sell parts? If we have them.

I realize you stated you have the one with the long pump, but that doesn't help identify your carburetor (there are at least 2 different long pumps, and at least 4 different short ones).

In fact, Carter made 42 DIFFERENT versions of the DRT-08. We have original prints and parts for most of them. The item that seems to be almost unique to a specific carburetor on these is the main discharge nozzle. If you look at the "head" end of the main discharge nozzle, there will be two numbers. The first is a 12 (meaning main discharge nozzle) and the second identifies which main discharge nozzle. Armed with that number I can consult my interchangeable parts list, and hopefully determine exactly which DRT-08 you have. With this information, I can then look up the bill of material and see if we have the parts you need. We have maybe 40 or so different standpipes, and 10 or so different choker cones.

Jon.

Do you have a diagram/photo of a main discharge nozzle?

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The main discharge nozzle is a brass tube with several holes of different diameters which is from maybe 3/4 inch to 1 1/2 inches. It has an oversize threaded head. The head of the main discharge nozzle will be exposed after removal of the bowl retaining nut. The nozzle screws into the same passage as the bowl retaining nut and extends into the bottom of the standpipe.

There are many different lengths, diameters, a couple of different threads; but they all resemble the above description.

Jon.

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I've finally got the brass parts out of the casting. All that is left is to dissolve the standpipe base in caustic soda. The DRT-08 carb which I have is a 158 which I believe is correctly sized for the 1930 DeSoto CK engine. I have a basic rebuilt kit (gaskets,pump seal, float valve) but will need a standpipe. What other parts are available? Main discharge tube, jets etc? Carbking, do you have these parts?

Thanks for the help

Rick VanOene

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Dose any one have reproduction stand pipes made out of better material ?

I have had  good luck cleaning other carbs by using lemon juice and water in a crock pot , usually  let it cook over night, keep an eye on it as  it can start to melt the pot metal.

Would this work on the stand pipe?

Is it necessary to taker the stand pipe out  to put a update kit in?

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Hello Isaiah

There are complete kits available for the DRT-08 carb. I purchase mine on ebay. The reproduction choke standpipe is made of aluminum. I boiled my housing in a water and lye mixture till the threads of the old standpipe remains were free to turn and unthread. Rebuilt the carb. It is on my car now and seems to work well.

Rick

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Would you have the kit number and did the choke standpipe come with the kit? or where did you get it

My carbs are brass bowl . the DRT 08 was on my car 1930 CJ6  and I picked up a RJH 08 this one looks to be a good carb  it has a single top housing where the DRT has two housings

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