Motorcraft 2150 2BBL Carb Rebuild- Welch Plugs?

[Bulletproof250]

Most parts stores used to carry carburetor adjusters, a long flexible shaft, or a curved tube with a flexible shaft inside it. The good ones had a sleeve like a screw starter to keep the bit engaged on the mixture screw.

OK so it's been a while that I've provided a update, but this one comes with more questions.

1. Is 7-turns too much to have the mixture screws out? (rhetorical)

2. Is the spacer under the carburetor need to be there? (EGR? PCV?)

4. Has anyone had trouble with the Vacuum operated diaphragm connected to the spacer?

3. Any recommendations for Gaskets when servicing the spacer?

I've considered removing the spacer to replace it with a simple "spacer" without any PCV/EGR plumbing.

The 7-Turn out was working pretty well, but It wouldn't allow for any idle adjustment below 1100 RPM, and the throttle plates were completely closed, was an indication to me that something was wrong, and it seem I found a decent leak in the EGR/PCV Spacer gasket.

[Gary Lewis]

OK so it's been a while that I've provided a update, but this one comes with more questions.

1. Is 7-turns too much to have the mixture screws out? (rhetorical)

2. Is the spacer under the carburetor need to be there? (EGR? PCV?)

4. Has anyone had trouble with the Vacuum operated diaphragm connected to the spacer?

3. Any recommendations for Gaskets when servicing the spacer?

I've considered removing the spacer to replace it with a simple "spacer" without any PCV/EGR plumbing.

The 7-Turn out was working pretty well, but It wouldn't allow for any idle adjustment below 1100 RPM, and the throttle plates were completely closed, was an indication to me that something was wrong, and it seem I found a decent leak in the EGR/PCV Spacer gasket.

Alex - I think you have a vacuum leak. I'm surprised that the idle mix screws didn't fall out at 7 turns, but you shouldn't need them out more than maybe 2 1/2 turns. So you have air coming in somewhere that you are compensating for by running the screws out. And that is why it won't idle below 1100.

And that spacer is a prime candidate for leaks. I don't know for sure which spacer you have, but it is probably an EGR spacer, and the "vacuum diaphragm" is probably the EGR valve.

This is a complex area. If you don't want to run EGR then you will need to change the ignition curve to compensate for the lack of exhaust gas in the mix. So I'd suggest you run EGR. But you absolutely have to make sure there's no leak of air in, and it is easy to have one there. In fact, some of the EGR spacers warped due to the heat and are very hard to seal.

Brand of gaskets. Not Mr Gasket, for sure. Holley or Motorcraft would be my pick.

[Bulletproof250]

Alex - I think you have a vacuum leak. I'm surprised that the idle mix screws didn't fall out at 7 turns, but you shouldn't need them out more than maybe 2 1/2 turns. So you have air coming in somewhere that you are compensating for by running the screws out. And that is why it won't idle below 1100.

And that spacer is a prime candidate for leaks. I don't know for sure which spacer you have, but it is probably an EGR spacer, and the "vacuum diaphragm" is probably the EGR valve.

This is a complex area. If you don't want to run EGR then you will need to change the ignition curve to compensate for the lack of exhaust gas in the mix. So I'd suggest you run EGR. But you absolutely have to make sure there's no leak of air in, and it is easy to have one there. In fact, some of the EGR spacers warped due to the heat and are very hard to seal.

Brand of gaskets. Not Mr Gasket, for sure. Holley or Motorcraft would be my pick.

Thanks Gary,

Now that I think about it, the diaphragm I'm seeing cannot be an EGR, since there is no connection to the exhaust. However it does have another hose coming from the Valve cover which I would imagine addresses PCV. That causes me to what to simplify, and disconnect that system even more. In my first call to the autoparts store, they were frustrated in their attempts to the correct gasket for it. in the meantime I found a Felpro Part number in my search of the web (FelPro 60528), any thoughts about this company? I'm all about OEM but, I hate working with the stealership guys.

[Gary Lewis]

Thanks Gary,

Now that I think about it, the diaphragm I'm seeing cannot be an EGR, since there is no connection to the exhaust. However it does have another hose coming from the Valve cover which I would imagine addresses PCV. That causes me to what to simplify, and disconnect that system even more. In my first call to the autoparts store, they were frustrated in their attempts to the correct gasket for it. in the meantime I found a Felpro Part number in my search of the web (FelPro 60528), any thoughts about this company? I'm all about OEM but, I hate working with the stealership guys.

If your spacer looks like the one below, it is EGR. And the exhaust comes through ports in the intake manifold to a slot below the spacer. The valve opens to let exhaust gas into the intake below the carb and dilute the air/fuel mix with inert gas.

As for gaskets, Felpro is a very good brand and I should have mentioned them.

[FuzzFace2]

If your spacer looks like the one below, it is EGR. And the exhaust comes through ports in the intake manifold to a slot below the spacer. The valve opens to let exhaust gas into the intake below the carb and dilute the air/fuel mix with inert gas.

As for gaskets, Felpro is a very good brand and I should have mentioned them.

Gary did you forget the picture

Alex, any way to post up a picture or 2 of this plate?

if this plate is ALUM they have been known to get holes in them from the gases and cause a vacuum leak / poor running motor.

Dave ----

[Gary Lewis]

If your spacer looks like the one below, it is EGR. And the exhaust comes through ports in the intake manifold to a slot below the spacer. The valve opens to let exhaust gas into the intake below the carb and dilute the air/fuel mix with inert gas.

As for gaskets, Felpro is a very good brand and I should have mentioned them.

Gary did you forget the picture

Alex, any way to post up a picture or 2 of this plate?

if this plate is ALUM they have been known to get holes in them from the gases and cause a vacuum leak / poor running motor.

Dave ----

Yes, I did.

[85lebaront2]

If your spacer looks like the one below, it is EGR. And the exhaust comes through ports in the intake manifold to a slot below the spacer. The valve opens to let exhaust gas into the intake below the carb and dilute the air/fuel mix with inert gas.

As for gaskets, Felpro is a very good brand and I should have mentioned them.

Gee, what did I say quite a while ago on the damn EGR plate. I used to stock them at Preston in a Motorcraft source box, both 2 barrel and 4 barrel versions. The highly corrosive exhaust gases will eat right through the inside of the spacer into the throttle bores.

[Bulletproof250]

Gee, what did I say quite a while ago on the damn EGR plate. I used to stock them at Preston in a Motorcraft source box, both 2 barrel and 4 barrel versions. The highly corrosive exhaust gases will eat right through the inside of the spacer into the throttle bores.

Thanks for the info. I thought i had the fix, a Felpro 60528. Looked great but as I took it out of the package and matched it up the the spacer, I noticed that window dimensions are different. the window of the gasket seems about 1/4'" more towards the bores in the manifold. This does look possible to seal the window from the outside, but it's not great it would have 1/8" actually compressed to make the seal, and restricts the rest of the flow.

Reading what you guys have taken the time and provided, I must note one thing, The valve on the back of the spacer, looks like the "EGR Valve" you guys speak of and show, however the piping goes to a tube that connects directly the the PCV Valve.

If you guys are familiar with the correct gasket, I'm open to go to the stealership even.

https://lh3.googleusercontent.com/moAMABmAox5YXoOy_9jqDiunwU8XF1xCxbPwI-hrM4D-PcRqZSeIHL1_FSUvPpLcQAiSOIPv26sbCecXjeAr3vl4czed0Oiqmq5JEAzTBF8dWpJFk113RhByX8g2uNI2Z4Q4VxA7Pw=w2400

The bottom looks like this one:

https://www.ford-trucks.com/forums/attachment.php?attachmentid=188735&stc=1&d=1499378204

 

[Gary Lewis]

Thanks for the info. I thought i had the fix, a Felpro 60528. Looked great but as I took it out of the package and matched it up the the spacer, I noticed that window dimensions are different. the window of the gasket seems about 1/4'" more towards the bores in the manifold. This does look possible to seal the window from the outside, but it's not great it would have 1/8" actually compressed to make the seal, and restricts the rest of the flow.

Reading what you guys have taken the time and provided, I must note one thing, The valve on the back of the spacer, looks like the "EGR Valve" you guys speak of and show, however the piping goes to a tube that connects directly the the PCV Valve.

If you guys are familiar with the correct gasket, I'm open to go to the stealership even.

https://lh3.googleusercontent.com/moAMABmAox5YXoOy_9jqDiunwU8XF1xCxbPwI-hrM4D-PcRqZSeIHL1_FSUvPpLcQAiSOIPv26sbCecXjeAr3vl4czed0Oiqmq5JEAzTBF8dWpJFk113RhByX8g2uNI2Z4Q4VxA7Pw=w2400

The bottom looks like this one:

https://www.ford-trucks.com/forums/attachment.php?attachmentid=188735&stc=1&d=1499378204

The thing I've circled is for sure an EGR valve. It should not be plumbed to the PCV valve, but for now you should disconnect it and plug the end of the hose as well as where it was connected. I say that because if you put vacuum to a good EGR valve it will introduce exhaust gas at idle, and it is not supposed to do that. So we need to figure out if the gasket is bad or if someone mis-connected it and that's the problem.

And I've added arrows showing the flow here:

[Bulletproof250]

The thing I've circled is for sure an EGR valve. It should not be plumbed to the PCV valve, but for now you should disconnect it and plug the end of the hose as well as where it was connected. I say that because if you put vacuum to a good EGR valve it will introduce exhaust gas at idle, and it is not supposed to do that. So we need to figure out if the gasket is bad or if someone mis-connected it and that's the problem.

And I've added arrows showing the flow here:

Thanks for the "..circles and arrows..", I wished I had the part in front of me right now, as I'm feeling as though I have vastly overlooked a gaping hole in the EGR Valve where the exhaust tubing connected, since I did not disconnect anything from it except for the vacuum hose that you see in the image there. The front of the spacer is plumbed to the PCV valve right?.

Am I crazy?

...you don't need to answer the last part, but I am narrowing down the correct gasket, A nearby parts store provided me with a closer match which, by their documentation is a fit for a '82 351W configuration. Maybe this last part could be a clue of mis-matched/ replaced engine or carburetor component??