Fuel Rails

Which end is the right end.

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Just a quick one this week. We spent ages trying to get a spark, and having taken it all apart, plugged everything back in twice and swapped a few bits over with a convenient donor (Ermy got worried when we approached her with spanners, last time we did that she was off the road for a while) we don’t really know why but it worked now. We had a spark. Moving swiftly on….

It wasn’t starting, ultimately because the fuel lines were the wrong way round.

I had followed advice on the internet, which was that the inlet for the fuel rail was “at the front”. Now I don’t know about you but on a fuel rail it isnt immediately obvious what is a front and a back, and I assumed front to be the front of the car. I also assumed the regulator was at the front, so that it regulated the fuel to the injectors.

Yep, we’re stupid, it’s not. We had thus pressurised the wrong end and no fuel was getting in. So, here is a diagram of the fuel rail including labels on which end is which.


The little space ship bit is the regulator. This is the output end of the fuel rail and sits the front of the car when installed. The fuel goes in at the bulkhead end and comes out at the front end.

The car doesn’t seem any worse for wear as a result of this problematic plumbing, but we have it all running now and after nearly a year, managed to get the body out into the sun.


Welcome to Twits with Spanner. A blog following two chaps as they attempt to build an Exocet kit car with bits from a donor MX5, spanners and lots of hope. Read more about us