John's Build

[DesertFox4]

Very nice John!

I also have one of Ron's radiators on my project. Phil had one made a few years back and never used it so it now resides on my 7SS. Ron makes beautiful aluminum radiators.

FWIW- when I replaces all my hoses last summer on the model 4, they were all still in very good condition. That was with 12 years and 900 hours of use.
Those silcone hoses should last forever.

[David47]

John, hi, my name is David Evans and I'm from Melbourne Australia. I'll be getting my Kitfox kit some time in the new year. In the meantime I've been following your build thread for couple of weeks. Mightily impressed with the way you're going about it. I have to thank you for giving me the inspiration to get stuck in to it and think laterally. Like Av8r3400, I just know that if you take the finished product to Oshkosh, you'll romp it in !. In the meantime, I'll be following your build and I'll also be posting when I start mine.

Cheers and keep up the excellent work.

Dave Evans

[jrevens]

Thank you Dave, Steve and Larry! It's really a gift to be able to participate in a forum like this. Sharing ideas has always been a joyful thing for me from the very beginning when I started to build my first homebuilt airplane, in 1975. My son was 6 months old then... he was 15 when I test flew it. I'm slow.

Dave, I look forward to following your progress! Good for you!

[cap01]

nice work john. wondering what silicon hose you used? i have a high time ul that the hoses should be replace and also a new engine on the way that i could change them while its easy.

[efwd]

Hey John, Im slower. I started an RV4 15 years ago and the boy was born. Never made it past the finished empennage. Wing parts still in box. LOL
Eh, Im having a great time with this one and the boys are helping when girls and video games have them too busy. So, nice job keeping it going while raising kids. And Thank You much for your posts and help.
Eddie

[jrevens]

nice work john. wondering what silicon hose you used? i have a high time ul that the hoses should be replace and also a new engine on the way that i could change them while its easy.

Hi Chuck,

I used hose, both straight & formed from several different suppliers. There is an awful lot of silicone hose available out there now, and the quality & selection seems to be better than it was only a few years ago. It's pretty tough stuff now, and you can get it meeting SAE & other standards. I saw a post on another site where it was stated that the writer didn't think that silicone was a good choice for an engine compartment, since there was a lot of oil & gas that it could be exposed to. Tell that to the race car builders. The fact is that you can even get silicone hose with a liner that is used as fuel line. I think the writer also missed the fact that the EPDM hose used by Rotax is not very compatible or recommended for use with oil or gas - to my knowledge. I've purchased it from 3 different suppliers (the first one is in Australia, where I bought some 11 mm fuel resistant hose for the 2 short sections on the carburetor balance tube) -

http://www.siliconedirect.com.au


http://www.siliconehose.com/
http://www.verociousmotorsports.com/...e-and-Fittings

I know there has been a lot of discussion about the 17mm ID distribution & return hoses to & from the heads. I wonder if Rotax chose that size to be able to corner the replacement market... it's very hard to find, and Rotax's prices for those small pieces of hose seem out of line to me. With silicone hose, I believe 5/8" ID should be perfectly fine, & what I used is compliant enough to stretch & conform nicely to the bulbed fittings on the heads & return tank - that's a single-ply "heater hose" rated at 5.4 bar. The combined cross sectional area of four 5/8" hoses is still considerably greater than that of the 1" ID hose that feeds & returns coolant to them. I've also found that the 5/8" hose I used curves nicely to replace the formed hose on the top/return of the rear head on the right side, without any appreciable restrictive deformation. 6' of the hose (black or blue color) that I used cost a little less than $23. This is a little bit of an experiment on my part, and I hesitate to recommend it to anyone else... proceed at your own risk.

[cap01]

john , thanks for the info and links. we have been doing some talking about the silicon hose and the question of the oil resistance did come up.

[jrevens]

You're welcome, Chuck.
A couple more points... silicone tubing has been used for fuel line for years by model builders. I have seen silicone that has been exposed to fuel & oil for many years that is just as supple as it was when new. I'm not an expert on this subject, but I read a long time ago that silicone rubber is not so much attacked by hydrocarbons as it is permeated by the smaller molecules. It's perfect for water & antifreeze, but fuel or oil can weep through it. The stuff just doesn't age like most other rubber materials. It also has a higher temperature rating.

[jrevens]

I sent in my paperwork for the registration to the FAA yesterday - a small step, but a good feeling. I've got a ways to go yet, but decided it was smart to register & pay $5 for a few years at a time instead of paying $10 every year to reserve my N number.

[N213RV]

Be advised that with registration comes the taxman looking for his share....