Claude,

With the engine running try spraying WD-40 around the manifold gasket, if it is leaking your engine will pickup RPM....My first thought was maybe water in gas/carburator but you have cleaned and adjusted that....I might suggest you install a vacuum guage on your vacuum port and run the engine just above an idle with the choke on, then see if the vacuum falls off when choke is opened, that should tell you if your problem is vacuum related.

Where Are You From? Leavenworth, WA / Yuma, AZ

Do You own a car built by Durant? several

More then likely the issue is within the carburetor by what you describe. Do you have a fuel sediment bowl before the carb to trap water and dirt? If not, install one after the vacuum tank. You will need to dismantle and pay special attention to cleaning the passages of the idle and high speed circuits. Make note of the idle and high speed jet settings so you can put them back during assembly.

Where Are You From? Hyattsville Md

Do You own a car built by Durant? Yes

Hello Bill,

Thank you for your kind advise. I tried the WD-40 approach as well as an unlit propane torch, but no rpm change. So I left the car in the garage for a few weeks and decided to reconnect the vacuum pump this morning. Well guess what! The engine runs as smooth as if nothing ever happened. Problem solved... mystery unsolved.

Thank you for the kind advise.

Claude Lavoie

Hello S. Blomquist,

Thank you for your kind advise. I left the car in the garage for a few weeks and decided to reconnect the vacuum pump this morning. Well guess what! The engine runs as smooth as if nothing ever happened. Problem solved... mystery unsolved. Probably water in the system somewhere.

Thank you for the kind advise.

Claude Lavoie

Hi Claude:
I think your problem may have been the vacuum hose not being hooked up. When you rehooked up the vacuum tank, the vacuum was closed off, thus fixing your problem.
Happy trails ahead.

Gord

Where Are You From? Guelph, Ontario, Canada

Do You own a car built by Durant? 1932 Frontenac built by Dominion Motors Limited, Toronto