23 January 2012

21st January 2012 - Air in the diesel supply

Twizzle and I were in transit to the Monday bank holiday ramble about Salisbury Plain with the Series 2 club when Trigger started to lose power while cutting across the back of Bulford ranges.

After pulling over to take a quick look the problem could be seen as soon as the hood was lifted. With some foresight all the fuel lines were run in clear 8mm hose so lumps etc. could easily be seen - and there was a tell tale stream of bubbles hitting the injection pump inlet. Not good.

So we limped home and had to take the Defender on an outing instead, much to the other leafers dismay (ended up recovering one ;) .

The source of the issue was found later in the day. I fitted manual ex-mil fuel selectors fitted (at great expense) to both the dual tank supply and returns during the rebuild. The problem is the supply selector - even fitted a new cork seal before it was bolted in but it is sucking in air. Now I had been warned that this 'may' happen but believing that even then this 'won't happen to me' I carried on and went for what I believed was the KISS principle ;) Now they don't wanna work too well on dieso and SVO!

Both of these military selectors work fine on petrol systems and I have overhauled and fitted new switches so they should fetch +£50 on 'the bay'. This will go towards the new Pevekoil fuel selector valves I have just had landed on the dining room table. These will be switched via a fused supply from an DPST switch on the dash which can also select the relevant fuel sender. This also gets around the usual issue on the microswitches with them seizing if not used for a while! Cost for a pair of valves and a few fittings was £90. A quality looking component but I am a bit concerned over the bore size/restriction through the valve. One port is only 4mm dia. and my current pipework is 6mm ID.


Initially the fuel system will be rigged up to the dieso tank and the changeover carried out gradually. I am finding grabbing enough time on one chunk is a bit strained at the moment ;)