Clutch Master Cylinder Line Adaptor

[mstrader77]

I'm working on a 1967 D100. The port threads on the new clutch master cylinder appear to be 1/4 npt. I don't have the original line. I thought an npt to inverted flare adaptor would be easy to source, but it's proving almost impossible. Did the original line or master use an adaptor? I can make it work, but want to make sure I'm not over complicating it. Thanks, Mark

[Wildergarten]

Did the original line or master use an adaptor?
Yes. I have seen both straight and 90° 1/4"NPT X 1/4" Inverted Flare fittings in that position.
Personally, I prefer the 90° fitting. To find one, look to a local company that makes up hydraulic hoses for heavy equipment and they'll probably be able to help you.

[mstrader77]

Thanks for the info. I just wanted to make sure I wasn't missing something obvious. I would think a master cylinder would come with the adaptor if they are so elusive to source. After 4 hours in Napa, Autozone, Orielly's, and finally Advanced Auto yesterday, I found a 1/4" npt to 1/4" flare fitting. I ordered a stainless braided hose (which I would prefer not to use) with an adapter, but its 1/8" npt. I'll probably use a reducer bushing and the stainless hose/adapter. I prefer factory appearing parts, but also a simple install, so the stainless hose will probably end up in the truck. I installed an A833 transmission, so my slave is directly under the master by a little over a foot or so, so there's not a lot of length for hard line plus a rubber hose section without it looking cobbled together. Thanks again for the info.

[mstrader77]

I contacted the manufacturer of the clutch master cylinder and they confirmed the port size is 1/4" npt, NOT 1/2"-20. They are updating their website with the correct information.

[Kaegi]

here is the part number for the correct clutch hose and the hose for the MC on the 4x4s and the D300 and up trucks

Dorman No. H79366

I think will need a male1/4 inv fl coupler to make it work

[mstrader77]

Thanks for the number. I had seen that hose, but it is too short for my setup. I wanted to secure the hard line to the frame and run a hose from there. This required about a 12" hose. I ended up installing a stainless braided hose from the master to the slave. 24" worked well. I used a -3 line. Normal clutch application feels adequate, but quick releasing feels like there is resistance to flow. I may have to change to a -4. It won't be on the road anytime soon, so the current setup will do for now.