delco1946 Posted March 12, 2020 Author Share Posted March 12, 2020 When I got my truck most of the emissions were gone. And not done correctly IMHO. I tried to get my EGR valve to work but without everything in the system, I could not. If the vacuum line goes direct to the valve with nothing in the line you’ll have vacuum all the time. I guess what im asking/wondering is have i connected to the correct connection under the carb? All the gizmos in line with the vacuum are restrictors, delays valves etc, so those only act to smooth and modulate vacuum fluctuations. The temp switches will open with a hot engine. But still with a hot engine at idle, i should not have vacuum at my egr, right? This make me question if the line is connected to the right port at the carb. I'm curious if anyone with a properly working 5.8L 351m can share where their egr vacuum source comes from? Link to comment Share on other sites More sharing options...
Frank Wyatt Posted March 12, 2020 Share Posted March 12, 2020 I guess what im asking/wondering is have i connected to the correct connection under the carb? All the gizmos in line with the vacuum are restrictors, delays valves etc, so those only act to smooth and modulate vacuum fluctuations. The temp switches will open with a hot engine. But still with a hot engine at idle, i should not have vacuum at my egr, right? This make me question if the line is connected to the right port at the carb. I'm curious if anyone with a properly working 5.8L 351m can share where their egr vacuum source comes from? Here's a vacuum port diagram for a Motorcraft 2150 carb I found on FTE. The "spark" port would be the ported vacuum source. https://www.ford-trucks.com/forums/1424779-for-anyone-who-needs-a-mc2150-vacuum-port-diagram.html I hope you find this helpfull. Link to comment Share on other sites More sharing options...
delco1946 Posted March 12, 2020 Author Share Posted March 12, 2020 Here's a vacuum port diagram for a Motorcraft 2150 carb I found on FTE. The "spark" port would be the ported vacuum source. https://www.ford-trucks.com/forums/1424779-for-anyone-who-needs-a-mc2150-vacuum-port-diagram.html I hope you find this helpfull. hmmmm that's a very interesting picture, thank you for that. I've been thinking about rebuilding my carb. i wonder if i might have some internal carb vacuum issues? It looks like my vacuum lines are all connected correctly. When i get home i play around with this more. Looks like the vacuum could easily be messing with my vacuum advance system. Link to comment Share on other sites More sharing options...
Frank Wyatt Posted March 12, 2020 Share Posted March 12, 2020 hmmmm that's a very interesting picture, thank you for that. I've been thinking about rebuilding my carb. i wonder if i might have some internal carb vacuum issues? It looks like my vacuum lines are all connected correctly. When i get home i play around with this more. Looks like the vacuum could easily be messing with my vacuum advance system. Yes, a bad/wrong base gasket could allow the ported vacuum port to get some vacuum all the time. Link to comment Share on other sites More sharing options...
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