Rubber Fuel Hose..., "Do not use as fuel injection hose" ?? Options

[Cap'n Krusty]

QUOTE (Tobra @ Feb 11 2006, 11:33 AM)

7.5 mm? I had always thought the D and L jet setups used 7 mm ID hoses. Also, the 914 does not have a single piece of the cloth braided fuel line, it is smooth with the reinforcement inside the rubber, which I sort of like better than the cloth covered stuff that was on the VW, since you can see the rubber with some facility.

It's smooth because it's all been replaced. The vacuum hoses, however, should all be the braided variety. The Cap'n

[Cap'n Krusty]

QUOTE (yarin @ Feb 12 2006, 11:48 AM)

So the pelican tech article is wrong? They used 5/16" rubber hose in the system. Should I not bother with the 5/16" SS lines i bought? Can I expect leaks? Thanks

PP isn't always the best reference source. Look at their valve adjustment article! Trust me, 33 years on 914s, and I've managed to learn enough about fuel lines that I've NEVER had a fuel related fire on a customer's 914 or 911. None of my own, either! The Cap'n

[Cap'n Krusty]

QUOTE (lapuwali @ Feb 12 2006, 12:50 PM)

5/16" = 0.3125" 7.5mm = 0.2952" So, 5/16" is 17 thou bigger, or just less than 0.5mm bigger.  5/16" is a better match for 8mm (only 2 thou smaller). I would've sworn the feed and return lines were different sizes on the 914, and one is 8mm.

Trust me, the .5mm makes a difference, as does the material from which the hoses are made. The 2 sizes are 7(or 7.5)mm, and 9mm. The 9mm is stepped down to the smaller size by an adapter hose going into the filter on the earlier cars. On the cars with the pump in the front, the filter is a bit larger on the inlet side, and the hose from the tank is a direct fit. I believe the 7mm hose has been supplanted by the 7.5mm, which fits without subjecting it to the strains involved with installing the smaller size in the metal fittings. German hose tends to have far less elasticity then the softer generic American fuel line. Even the standards for vacuum line make it much more difficult to install. The Cap'n

[yarin]

Summit doesn't sell 7 or 7.5mm fuel hose. Pelican only sells 7 or 8mm hose. I'm starting from scratch converting carbs to MS and replacing the tunnel lines so i'd rather do it right the first time.

I have a stock fuel pump, engine compartment mount. '73 2.0 injectors and fuel rail. What is the correct diameter fuel injection hose to use? 7mm or 7.5mm? I take it the Cap'n doesn't like 5/16".

I was considering making my own fuel rails for use with stock injectors. Tap the block and stick some 5/16" barbed nipples on them. Good idea?

Thanks.