I just bought a 1987 744 gle with aged hoses. Does anyone know how many feet of each size hose I need to replace all of the vacuum lines? I searched but could not find it here.

 

Sorry I do not know off hand but I know it is pretty much all the same size.

 

I did my new 940 last weekend (engine bay only so far) I brought 6 feet and lots left.

 

Cool. Which ID did you use? Was it just right, or would you use a little bigger/smaller if you were to do it over?

 

Actually I don't know the size. I had a nipple out cleaning the breather box and took it down to Papco and I just test fitted until I got something I liked. I looked at it today and there is no ID on it, just black hose. Same size fits almost everywhere.

 

On my 1991 the factory vacuum hoses are marked 4.2mm. Most replacement hoses that i've found are 4mm. They stretch pretty easily.

Cheers, bt

 

I got all the hose from Advance Auto Parts, so they carry not-metric hose. The Dorman vacuum fitting packages give metric equivalents to the inch sizes. I measured the actual fitting diameters using an inexpensive, what's the word, caliper? micrometer? that I got at Harbor Freight and the lengths with a tape measure. I rounded up a tad in lengths, best too long and trim then too short.

1. brake booster vacuum line: 3/8" ID x 12.25 " length
2. fuel pressure regulator to throttle body: 5MM (3/16") ID x 11" length
3. flame trap nipple to throttle body: 5MM (3/16") ID x 9.25" length
4. flame trap to intake hose: 16MM (5/8") x 11.5" length
5. intake hose to sensor? 3/4" ID x 18.25" length
6. sensor? to intake manifold: 3/4" ID x 11" length
7. intake manifold to vacuum tank in front bumper: 3/8" ID x 7 feet length (this hose tees to hvac control system, and has the hvac check valve in it).
8. throttle body to evap canister, small: 3.5MM (1/8") ID x 40.25" length (on my car, at least, this was a 1/8" OD hard line with replaceable rubber ends - I reused the line and bought new ends: 1/8 ID x 1/8 ID 90 deg elbow to throttle body and 1/8 ID to 3/16 ID straight to canister)
9. throttle body to evap canister large: 7/32" ID x 41.5" length. The 7/32" works but was a tad tight at the throttle body, 5/16" was too loose. Next time I'll try harder to find 1/4" ID.

I decided not to replace # 4, 5, or 6. They were in good shape and had significant bends built in, and would be difficult to replace with off the shelf hose. I'll try hose clamps to make sure they're vacuum tight. There also is a third vacuum line going from the evap canister to disappear down the frame rail toward the back. The main line is a hard line, with a rubber end connection that was in good shape, so I left it alone, too.

 

And after doing all the above, I now find one of our friends at brickboard pointed me to the vaccum hose FAQ section I had missed until now:

http://www.brickboard.com/FAQ/700-90...oseReplacement

So, you can go domestic at the FLAPS like I did, or use the brickboard FAQ and buy metric by mailorder.

Hopefully the combination of info here will be useful to another newbie like me...

 

Glad all is good now with it.