I'll give new vacuum line a whirl first. My thought had been it was hard plastic because of the pressure, but if it was done for cheapness, I'll gladly go soft.

The original lines are plastic but regular vacuum line will work fine.

Still a quandry...
 

Unfortunately I have not found any vacuum lines that will do to replace this Cub Cadet hard line. The line is about an eighth inch OD, so I've been looking for a soft vacuum line that would fit over it tightly.

I cannot just replace the line with soft line because the CC fitting is designed for the hard line to insert into it, and you can't do that with a soft line. I could mess with the basis of the fitting to see if I could jury-rig a standard fitting, but am taking a real risk because some of those parts are no longer available.

I have found some gas line that fits over the existing hard line and will try that once the engine is running, hopefully in a few days. However, if there is any substantial vacuum involved, I'm afraid it will collapse. This is the vacuum that moves the idler pulley to engage the PTO and mower.

I have run into online complaints by many about hard plastic vacuum lines from moderately old cars - Ford products frequently - because they can't find the lines either today.

30" of vacuum is the ultimate and perfect vacuum. It is un-attainable without being in a lab and having the ultimate equipment.

That being said, there is no way that some small engine manufacturer is going to create so much vacuum that it will collapse a standard "vacuum hose".

:ThumbsUp:

Look up the factory parts on Parts tree or the Cub site and order them if you are concerned about the ability of a non factory part doing the job. Wish I had a better answer for you but I don't and I'm not trying to be a smart A$$.

Do you have any of the original line? If you do, just cut a couple inches off and push it into the new hose on both ends. On my GT3100 they use regular fuel line and it works okay. On my 3165 they have a barbed fitting on the intake that will take regular hose.
If all else fails call Rich Patton at the top of the page. I bet he can hook you up.:beerchug:

McMaster has lots of tube. They have an 1/8" od nylon tube rated for vacuum, only 28", not 30". :biggrin2: It works with push to connect fittings which I'm guessing is what your describing; so it's a pretty stiff line. You can even get it in yellow. :beerchug:

www.mcmaster.com/#5548k61/=ycvuse

Bill

So..... get 1/8" vacuum line. I don't know where your getting that this engine makes huge amounts of vacuum. It doesn't make any more than any other engine. Should be pulling around 10"-14"Hg at any given time. (That's an approximate number.) It's really, really simple. Get some vacuum line, and attach it. Don't make this harder than it is.

AMEN! ----18"maybe downhill, closed throttle, with a tail wind on a exceptional day :biggrin2:

All good info.... Thanks. As I mentioned, I'm planning to use some of the old line at each end to insert into new tubing. My only concern is that the only new tubing I've found so far that fits is clear fuel line, and I'm not sure how good it will be with a vacuum. If it doesn't work I'll try to find some conventional vac line that's close in size and see what I can do to make it fit.

I would have ordered new vac line from Cub Cadet or one of the parts suppliers, but I cannot find it listed anywhere on any site. It's odd that CC would use this very specific hard plastic vac line on a bunch of 1990s models and not have it available for purchase. Mine can't be the only unit that has broken the line.