Debra
11-29-2007, 03:42 PM
Hello Clarence, I sure hope you can help with this:
I have an old OS FS-120 Surpass with Pump that I purchased new in late 1989. It has never run right and only has a few hours of use on it as it would never stay running. I seem to recall an article from your column many years ago stating that the pump pressure was set too high from the factory. I seem to recall your recommending putting a "Tee" in the line from the pump to the carb and routing the tee to return to the tank. I have tried this and with the reduced pressure to the carb, the needle valve seems to be ineffective and it appears to be running lean as might be expected. If you can recall what the correct fix is for this problem, I would really appreciate your passing it along to me.
Thank you,
Richard M.
Dear Mr. M.,
If the "T" in the fuel line didn't solve the problem, then the problem lies elsewhere, probably the pump itself. However, be sure that the "T" is installed as close to the carburetor as possible and use a separate return line. I know of several cases where fellows connected the return line to the tank vent which kept the tank from venting. Also be sure the tank is venting okay. If everything is okay here, then install a short length of small i.d. brass or copper tubing in the return line to restrict the return fuel flow and supply more fuel to the carburetor. Also be sure that there isn't a restriction in the carburetor, foreign matter, etc. If the problem still persists, install
a pressure fitting on the muffler and connect the fuel tank directly to the carburetor, i.e., bypass the pump and use muffler pressure. These early pumps did have problems, hence the Surpass II and III series. Let us know what you find.
Yours,
Clarence Lee
I have an old OS FS-120 Surpass with Pump that I purchased new in late 1989. It has never run right and only has a few hours of use on it as it would never stay running. I seem to recall an article from your column many years ago stating that the pump pressure was set too high from the factory. I seem to recall your recommending putting a "Tee" in the line from the pump to the carb and routing the tee to return to the tank. I have tried this and with the reduced pressure to the carb, the needle valve seems to be ineffective and it appears to be running lean as might be expected. If you can recall what the correct fix is for this problem, I would really appreciate your passing it along to me.
Thank you,
Richard M.
Dear Mr. M.,
If the "T" in the fuel line didn't solve the problem, then the problem lies elsewhere, probably the pump itself. However, be sure that the "T" is installed as close to the carburetor as possible and use a separate return line. I know of several cases where fellows connected the return line to the tank vent which kept the tank from venting. Also be sure the tank is venting okay. If everything is okay here, then install a short length of small i.d. brass or copper tubing in the return line to restrict the return fuel flow and supply more fuel to the carburetor. Also be sure that there isn't a restriction in the carburetor, foreign matter, etc. If the problem still persists, install
a pressure fitting on the muffler and connect the fuel tank directly to the carburetor, i.e., bypass the pump and use muffler pressure. These early pumps did have problems, hence the Surpass II and III series. Let us know what you find.
Yours,
Clarence Lee