Stens TruBlue Short term test results.

[KE4AVB]

Got in touch with Stens technical department on the sizing problem. I am not the only one that is having an issue with the line fitting my application. I was on the phone with them nearly a 1/2 hour. They wanted as many make and models that currently I had in the shop that I could give then. All I had left to get actual numbers from was 4 blowers. It took a while to get it through them that these Poulans (Weedeater, Poulan Pro, Poulan Wildthing, and Craftsman) were the same 25cc unit just in different colors. The technician also keep mentioning about fuel grommets and I finally (I think I did) got it through to him that these tanks use fiction fit and not grommets. I even offered to send a sample their line and the Tygon line that it was supposedly to replace.

He said the line he had in front of him measured correctly. He thought I crushing the line in my caliper so I remeasured the line by my Tygon in jaws first and at the same time place their line in beside the Tygon. Their line just fell through the jaws opening. The only thing could we come up with is that line I got was mislabeled. That is possible and could explain why others are having the same problem.

As for the line test, After 3 weeks in my fuel mixture the line is still stable after the initial color change and slight softening. So appear to be a good line to use; just wish the size was as advertised.

[KE4AVB]

Well I thought I would post an update with results of my tests.

The Stens True Blue failed my tests. I started the test around Oct 1, 2015. As today Nov 19, 2015 the results are not good. This was a side by side comparison to Tygon F-4040a.

• First the line changed color; no big deal.
• Line soften some in fuel mix but stay stable while completely submerged and didn't swell or shrink.
• The problem arise when removed from the fuel submergence it shrunk by 1/64 in diameter and has gotten very stiff. Initial size 11/64 end result 5/32. Doesn't looks like much but this small size it very to see on side by side comparison of new to used.
• While Tygon F-4040a line only had slight color change probably from the fuel dye with no shrinkage, swelling, hardening or softening.
  

From this I gather that the line would not suitable for in tank use where the fuel must able to move around during use and the tanks are stored dry after use.

Now I have seen the Tygon F-4040a exhibit shrinkage, swelling, hardening and softening but it have been usually over several years of use. Nothing like the True Blue did in my short term tests.