| classical glass |
04-17-2019 06:25 AM |
Secondary Diaphragm Question
I have a 427 side oiler with two 650 Holley 4 barrels. I'm thinking I might have a vacuum leak but not sure. There is a small rubber hose (aprox 3/16 ID) that goes from the front carb diaphragm to the rear one on the left side of the carbs. If I pull one end off and apply a vacuum coarse I get nothing, no vacuum will accumulate. Should it hold a vacuum or is it open to atmosphere? I'm getting all kinds of theories but I want to be sure.
Thanks.**)
|
| Jerry Clayton |
04-17-2019 07:39 AM |
That is to balance the opening of both carbs seconaries at same time
|
| DanEC |
04-17-2019 05:03 PM |
Where those diaphragm housings bolt to the carburetor body there is a small cork o-ring gasket that seals the vacuum passage from the carb. It's something than can go bad or may have got lost or misplaced when someone had them apart. That would prevent building vacuum although if you can't get either carb diaphragm to hold vacuum with a pump - it would be a bit unusual to be missing the gasket on both of them. If this is your issue you aren't getting secondary throttle either.
|
| Gaz64 |
04-17-2019 06:54 PM |
Quote:
Originally Posted by classical glass
(Post 1460685)
I have a 427 side oiler with two 650 Holley 4 barrels. I'm thinking I might have a vacuum leak but not sure. There is a small rubber hose (aprox 3/16 ID) that goes from the front carb diaphragm to the rear one on the left side of the carbs. If I pull one end off and apply a vacuum coarse I get nothing, no vacuum will accumulate. Should it hold a vacuum or is it open to atmosphere? I'm getting all kinds of theories but I want to be sure.
Thanks.**)
|
That hose is fitted to balance the two diaphragms, so the two secondaries open by the same amount at the same time.
Between the two housings, there is venturi vacuum in that hose, not manifold vacuum.
What symptoms do you have, if you believe you have a vacuum leak?
Gary |
| All times are GMT -7. The time now is 10:30 AM. |
|
Powered by vBulletin® Version 3.8.0
Copyright ©2000 - 2025, Jelsoft Enterprises Ltd.
Search Engine Friendly URLs by vBSEO 3.6.0
The representations expressed are the representations and opinions of the clubcobra.com forum members and do not necessarily reflect the opinions and viewpoints of the site owners, moderators, Shelby American, any other replica manufacturer, Ford Motor Company. This website has been planned and developed by clubcobra.com and its forum members and should not be construed as being endorsed by Ford Motor Company, or Shelby American or any other manufacturer unless expressly noted by that entity. "Cobra" and the Cobra logo are registered trademarks for Ford Motor Co., Inc. clubcobra.com forum members agree not to post any copyrighted material unless the copyrighted material is owned by you. Although we do not and cannot review the messages posted and are not responsible for the content of any of these messages, we reserve the right to delete any message for any reason whatsoever. You remain solely responsible for the content of your messages, and you agree to indemnify and hold us harmless with respect to any claim based upon transmission of your message(s). Thank you for visiting clubcobra.com. For full policy documentation refer to the following link:
