Carb/Intake Gasket seal

Posted by Bob E. On 2019/9/14 16:10:46

Hi,
Been fighting an idle and high rpm miss for a while (see project blog):https://packardinfo.com/xoops/html/modules/newbb/viewtopic.php?topic_id=20490&viewmode=flat&order=ASC&type=&mode=0&start=70

I've been trying everything to isolate with no luck. last week, I removed the intake manifold (with carb attached) and now that I reinstalled it, it runs even worse and won't idle below 700rpm. Very much a vacuum leak. Took some starter fluid and was spraying around the carb/manifold interface. When I squirted the driver side throttle shaft area, the rpm picked up. Due to the linkages, I can't tell if the rpm changed when the fluid hit the throttle shafts or the carb/manifold interface. Carb was rebuilt by Daytona so I am assuming they would have checked a need to re-sleeve the throttle shaft bores.

I pulled the carb off and as you can see from the attached photo, there is no indent in the gasket from the manifold side on the driver side, but a noticeable one on the passenger side. This makes we want to believe this is the source of the vacuum leak. I checked the carb nuts torque several times so I know each 4 nuts were the same. Should I just crank harder on the driver side? Or is there some RTV type material I could use and trust? I'm hesitant to use anything that fuel may deteriorate and end up in the engine.

I've had a miss since before I tore my engine apart, not sure this is related. Anyone have experience with these intake manifolds warping a little and need to be machined? I guess it could be the carb face could be the culprit too and bending when I torque down the nuts.

thanks
-Bob

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