DJ254 - New DHC - fuel changeover tap

Fossil
Posts: 380
Joined: Sat Feb 13, 2016 5:08 pm
Location: Helensburgh, Argyll

Re: DJ254 - New DHC - fuel changeover tap

Post by Fossil » Tue Aug 29, 2017 6:24 pm

I bought corks from John Nash also. I hadn't anticipated the difficulty of removing the rigid fuel pipes from the valve body before I started the job, so the decision to remove the outlet pipe first was made on the hoof. I didn't drain the fuel tank, I think I used shallow aluminium oven roasting pans to collect the fuel that poured out and connected the two inlet pipes together with a length of fuel hose once the valve was removed, so of course the valve had to be disconnected from the chassis and the operating cable first. After some thought and care surprisingly little fuel was spilled, so it wasn't as dangerous an exercise as it sounds (although not within COSHH regulations), and much care was taken to avoid causing sparks of course. I tried not to inhale too much as well in order not to dissolve my liver cells in petrol vapour.

Cheers

Geoff

qantasqf1
Posts: 90
Joined: Mon Mar 07, 2016 10:13 pm

Re: DJ254 - New DHC - fuel changeover tap

Post by qantasqf1 » Wed Aug 30, 2017 7:32 pm

Just one detail that I don't think has been mentioned. There may be a tiny grub screw that's threaded in the plunger near the clevis end and it locks the long central screw that holds the seals and spacers in place. It's there to prevent the long plunger screw from turning: if it did turn it would reduce the seal between the 2 cork seals and the body so it would leak fuel. Release this grub screw a couple of turns before unscrewing the plunger's central spindle or its threads will be damaged. Finally, there should be a hole in the end of the brass body. When you fit the plunger to the body you can leave the long central screw fairly loose: this makes it easy to fit because the cork seals aren't compressed so there's no risk of damaging them. When the plunger is home a small electrical screwdriver can be fitted through this hole and the central screw can be tightened by it until the (now compressed) seals give the best 'feel'.
Steve

Salmons
Posts: 334
Joined: Thu Feb 11, 2016 7:56 am

Re: DJ254 - New DHC - fuel changeover tap

Post by Salmons » Wed Aug 30, 2017 9:17 pm

The grub screw is visible on my photographs.
Dennis

qantasqf1
Posts: 90
Joined: Mon Mar 07, 2016 10:13 pm

Re: DJ254 - New DHC - fuel changeover tap

Post by qantasqf1 » Thu Aug 31, 2017 8:54 am

I think you may be referring to the screw that limits the travel of the plunger and guides it. That's not what I was referring to - the grub screw is tiny affair and can go unnoticed. It's threaded into the plunger itself, not the body.

Beat Weibel
Posts: 100
Joined: Sat Feb 27, 2016 4:13 pm
Location: Switzerland

Re: DJ254 - New DHC - fuel changeover tap

Post by Beat Weibel » Sun Jul 08, 2018 4:24 pm

Finally, I managed to do the job. That's how the interior looks like with old corks.
BR and many thanks for your help
Beat
Pic 1.JPG

Beat Weibel
Posts: 100
Joined: Sat Feb 27, 2016 4:13 pm
Location: Switzerland

Re: DJ254 - New DHC - fuel changeover tap

Post by Beat Weibel » Sun Jul 08, 2018 4:27 pm

Pic 2.JPG

Post Reply