1985 F150 Vacuum Leak

Doug 845

Senior Member
I have a F150 with the 4.9 liter engine with a new 1 barrel carb. I have a vacuum leak at the base of it after installation. I went to order another gasket and now see that it mentions a spacer on the gasket description. Did these engines come with a spacer between the intake & carb? If so, where do I get a spacer? When I removed the old carb, I threw out the old gaskets / materials that were under the carb. The engine runs great with the new carb, but has a slight vacuum leak.
 
Thanks for the reply. I found both gaskets. The weird thing is that there is no spacer to be found anywhere. I called my local Ford dealer and he looked at a schematic and couldn't tell even if there ever was one for my F150 4.9L engine. I believe that only gaskets are needed, and even that I believe that I only need one since there is no spacer needed.
 
Thanks for the reply. I found both gaskets. The weird thing is that there is no spacer to be found anywhere. I called my local Ford dealer and he looked at a schematic and couldn't tell even if there ever was one for my F150 4.9L engine. I believe that only gaskets are needed, and even that I believe that I only need one since there is no spacer needed.

The gaskets go between the carb and EGR SPACER and then spacer to manifold. Sounds like someone pulled a not too careful EGR DELETE on the engine. I don't have this period TRUCK PARTS CATALOGING or I would pull out all the info for you.

The ILL I showed shows the spacer with attached EGR VALVE and A.I.R. hookup.

One good quality gasket should seal the carb base to the intake if both surfaces are good. Make sure the studs are not too long as this will not allow the carb base to be tightened sufficiently.
 
I have a 85 300 6 in my 56 F100. 1985 had a weird emissions set up with a electronic mixture solenoid and a early style of computer controlled advance. I switched mine to a late 70's style vacuum advance dura spark dist. and a 73-75 Carter YF carb. Mine had that goofy spacer you can't find. I had to make a gasket for the spacer to intake but just bought a gasket for the carb to spacer. Seems like I remember I removed the tube which threaded into the spacer (the other end went to a EGR valve) I was able to thread a pipe plug into the spaced which doesn't fit just right but seems to work OK. I'll try to get some pics. I think you will have to go to a salvage yard and hope you can find a 85 300 in a pickup or van. Good luck!!
 

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Sorry those pics weren't what I meant to get, I'll try again.
 

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I replaced the carb to spacer gasket with a NOS gasket I found online. Worked great. The vacuum is pretty steady @ 21. I was under the impression that a spacer was just a flat piece of metal about an inch thick, not something that the EGR valve bolted onto. Thanks to everyone for their help.
 
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