Distributor vacuum fitting for Motorcraft 4100

[knn]

Anyone know where to find the distributor vacuum fitting for a Motorcraft 4100 (4 barrel) carb?  I bought the carb and have rebuilt it, but it's missing the fitting so install is on hold.

 

[c9zx]

Anyone know where to find the distributor vacuum fitting for a Motorcraft 4100 (4 barrel) carb?  I bought the carb and have rebuilt it, but it's missing the fitting so install is on hold.

Are you looking for a threaded male end into the carb with a slip on hose on the other side, or male threaded (different sizes) on both ends? Chuck

 

[knn]

Anyone know where to find the distributor vacuum fitting for a Motorcraft 4100 (4 barrel) carb?  I bought the carb and have rebuilt it, but it's missing the fitting so install is on hold.

Are you looking for a threaded male end into the carb with a slip on hose on the other side, or male threaded (different sizes) on both ends? Chuck

So sorry, I never saw this response and have been away from the forum.  

I still haven't solved the problem.

I'm looking for a barb fitting that screws into the distributor vacuum port (so I can use a rubber hose) or the correct brass fitting so I can plumb in a hardline to the distributor.  

My car is a 71 Mach 1 w/ 351c.  I know the Motorcraft 4100 was never original on that car, but I'm hoping one of you guys with a 60s Mustang would know what I'm looking for.

Thanks so much,

Nick

 

[Hemikiller]

The 65-ish 4100 I have has an 1/8 NPT fitting with the original compression seat on the distributor side. I'd recommend an 1/8" NPT male to 1/8" or 3/16" tube to run the rubber vacuum hose.

https://www.summitracing.com/search/part-type/universal-fittings/fitting-category/npt-to-hose-barb/fitting-attachment-style-1/male-npt/fitting-size-1-application/1-8-in-npt/fitting-angle/straight?SortBy=DisplayPrice&SortOrder=Ascending&N=fitting-angle%3Astraight%2Bfitting-size-2-application%3A1-8-in-hose-barb_3-16-in-hose-barb

You should be able to find them at your local hardware store in the plumbing section.

 

[knn]

The  65-ish 4100 I have has an 1/8 NPT fitting with the original compression seat on the distributor side. I'd recommend an 1/8" NPT male to 1/8" or 3/16" tube to run the rubber vacuum hose.

https://www.summitracing.com/search/part-type/universal-fittings/fitting-category/npt-to-hose-barb/fitting-attachment-style-1/male-npt/fitting-size-1-application/1-8-in-npt/fitting-angle/straight?SortBy=DisplayPrice&SortOrder=Ascending&N=fitting-angle%3Astraight%2Bfitting-size-2-application%3A1-8-in-hose-barb_3-16-in-hose-barb

You should be able to find them at your local hardware store in the plumbing section.

Do you think it could be any other size?  I bought a 1/8" NPT male to 1/8" tube and it won't screw in.  Both sets of threads look fine, but the 1/8" NPT seems too big and a slightly different thread.

Thanks,

Nick

 

[Hemikiller]

The  65-ish 4100 I have has an 1/8 NPT fitting with the original compression seat on the distributor side. I'd recommend an 1/8" NPT male to 1/8" or 3/16" tube to run the rubber vacuum hose.

https://www.summitracing.com/search/part-type/universal-fittings/fitting-category/npt-to-hose-barb/fitting-attachment-style-1/male-npt/fitting-size-1-application/1-8-in-npt/fitting-angle/straight?SortBy=DisplayPrice&SortOrder=Ascending&N=fitting-angle%3Astraight%2Bfitting-size-2-application%3A1-8-in-hose-barb_3-16-in-hose-barb

You should be able to find them at your local hardware store in the plumbing section.

Do you think it could be any other size?  I bought a 1/8" NPT male to 1/8" tube and it won't screw in.  Both sets of threads look fine, but the 1/8" NPT seems too big and a slightly different thread.

Thanks,

Nick

At this point, I'd just get an 1/8"-27 NPT tap and make it work. The closest straight thread to it is 3/8"-24, you could try threading a bolt in and see if it threads better.

 

[knn]

The  65-ish 4100 I have has an 1/8 NPT fitting with the original compression seat on the distributor side. I'd recommend an 1/8" NPT male to 1/8" or 3/16" tube to run the rubber vacuum hose.

https://www.summitracing.com/search/part-type/universal-fittings/fitting-category/npt-to-hose-barb/fitting-attachment-style-1/male-npt/fitting-size-1-application/1-8-in-npt/fitting-angle/straight?SortBy=DisplayPrice&SortOrder=Ascending&N=fitting-angle%3Astraight%2Bfitting-size-2-application%3A1-8-in-hose-barb_3-16-in-hose-barb

You should be able to find them at your local hardware store in the plumbing section.

Do you think it could be any other size?  I bought a 1/8" NPT male to 1/8" tube and it won't screw in.  Both sets of threads look fine, but the 1/8" NPT seems too big and a slightly different thread.

Thanks,

Nick

At this point, I'd just get an 1/8"-27 NPT tap and make it work. The closest straight thread to it is 3/8"-24, you could try threading a bolt in and see if it threads better.

I may have to head down that path.  Here's what I found in another forum:

I don't think that the 65 should have a 1/8 pipe thread for the vacuum by the pictures of the carbs with adapters it looks like the male thread is 1/8 on them, the 65 should be a tube thread which they call a "brass threaded tube ftitting"it has a crush sleeve formed on the end to grab the tube it measures .370" dia. X 24 thread part number 181-3, 1/8" pipe is a taper thread .385-.395" at the big end x 27 thread.

 

[Hemikiller]

Do you think it could be any other size?  I bought a 1/8" NPT male to 1/8" tube and it won't screw in.  Both sets of threads look fine, but the 1/8" NPT seems too big and a slightly different thread.

Thanks,

Nick

At this point, I'd just get an 1/8"-27 NPT tap and make it work. The closest straight thread to it is 3/8"-24, you could try threading a bolt in and see if it threads better.

I may have to head down that path.  Here's what I found in another forum:

I don't think that the 65 should have a 1/8 pipe thread for the vacuum by the pictures of the carbs with adapters it looks like the male thread is 1/8 on them, the 65 should be a tube thread which they call a "brass threaded tube ftitting"it has a crush sleeve formed on the end to grab the tube it measures .370" dia. X 24 thread part number 181-3, 1/8" pipe is a taper thread .385-.395" at the big end x 27 thread.

Agree with that post and the thread they posted is simply 3/8-24. The crush fittings are available as part of the reproduction vacuum advance tube that's available, but they aren't made for a 351C.

 

[knn]

At this point, I'd just get an 1/8"-27 NPT tap and make it work. The closest straight thread to it is 3/8"-24, you could try threading a bolt in and see if it threads better.

I may have to head down that path.  Here's what I found in another forum:

I don't think that the 65 should have a 1/8 pipe thread for the vacuum by the pictures of the carbs with adapters it looks like the male thread is 1/8 on them, the 65 should be a tube thread which they call a "brass threaded tube ftitting"it has a crush sleeve formed on the end to grab the tube it measures .370" dia. X 24 thread part number 181-3, 1/8" pipe is a taper thread .385-.395" at the big end x 27 thread.

Agree with that post and the thread they posted is simply 3/8-24. The crush fittings are available as part of the reproduction vacuum advance tube that's available, but they aren't made for a 351C.

Yep.  We've heard so many war stories about trying to get 4300 and 4300-D tuned right that we decided to go 4100. It's not stock, but hopefully, it will work for us.

I think the older carbs had a better solution (3/16 tube x 1/8 NPT adapter), but I suspect Ford may have changed that to reduce costs and number of parts.  If you have a new carb as I do, I think the best solution is a buy the distributor hard line for an older Mustang and just cut the end off.  These are readily available, here's the CJ link, https://www.cjponyparts.com/classic-tube-distributor-vacuum-line-original-steel-289-1965-1966/p/MUA1003O/

Thanks all,

Nick