Poor running - Fuel Tank Replcements

[hoops]

I have posted a couple of times on the Facebook group but thought I would post here to keep track a bit easier.

I bought my Dolomite 1850HL back in August, and ended up bringing it home on the back of a recovery truck as it started spluttering and cutting out not long after I filled up with fuel. Long story short I think when I brimmed the tank, it bought up a whole load of crud from the bottom of the tank.

Since then, I've had some electrical issues and it seemed to be running fine'ish other than not revving over 3,500rpm. Since then I have now replaced the following:

New Coil & Electronic Ignition via the SimonBBC kit
New Magencor HT Leads via the Club
New Distributor Cap (Rotor looks fine and is nice and clean)
New Spark Plugs
New Fuse Box
New Hazard & Indicator relays (not ignition related but now all working)
Checked wiring on the ignition switch and all seems fine, sprayed with contact cleaner and driven while wiggling the cables and no cutting out.

Broken earth cables on the back of the Tachometer and in the distributror (from vacuum advance to mounting plate) have been repaired.

Since then, the car now revs fine both under idle and under load past 3,500rpm, and will happily sit on the drive for 10-min. Take it out for a drive and a few minutes down the road it starts to splutter, not rev and then cut out. I can usually manage to get it going after trying for 20-30 seconds and pulling the choke cable out a few times, pumping the accelerator etc.

I have cleared out the carb float chambers a couple of times now, there was a fair few small bits of stuff in them both times, as well as replacing the fuel filter twice.

I can only think that the continued issue is the fuel supply and that a replacement tank might be the only option?

Are there any other solutions other than a new one via ChrisWhittor?
https://www.chriswitor.com/proddetail.php?prod=312385A

Unless there is anyone in the Oxfordshire/Swindon area who could double check I've not missed anything?

[Carledo]

I agree your problem is most likely related to fuel flow, I seem to recall this car was stood for some time before your purchase.

That being the case, I would carefully check all the solid fuel pipes for blockage/restriction, the bit that goes up over the axle is particularly prone to blockage with calcified crud when left standing. One I have here that looks perfect and I use for a pattern to make new ones, is so thoroughly blocked that 100psi of air pressure won't clear it and nothing is rigid enough to clear the blockage (which is, of course , right in the middle!) but flexible enough to go round the tight corners! Also, replace all the rubber fuel hoses (most emphatically including the 3 under the car) with new ethanol compatible R9 hose and take care to get a good known make like Gates Barricade, there are a lot of fakes out there!

Pay especial attention to the pipe in the bottom of the tank as i've seen these blocked solid with crud or only letting a trickle of fuel through, enough for idling, but not for sustained running at higher revs. I like to rod this out with an opened up wire coat hanger - assuming you can find one these days!

Take the tank sender out and examine the bottom of the tank for crud and corrosion, if it's too bad, then a replacement tank is the best option. If it looks clean and silver around the end of the pickup tube then the tank is probably OK and the pipes just need a clear out.

One more thing, check carefully that the fuel filler cap is of the vented design, a non vented cap will create a vacuum in the tank that stops the pump from pumping in quite short order! Some Triumph caps are made with the 3 prong fitting , but without vents as their tanks are separately vented.

I have the facilities here to bend up new copper fuel pipes if you need some, but, once made, they'd be impossible to post, you'd have to collect from South Shropshire WV16!

There really aren't any NEW tanks available except Chris Witor's Alloy offering, it's a lovely thing but i'd regard it as a last resort, purely on cost grounds! However the news is not all bad, there are still a few good used tanks in the world, I have a couple myself. I'm sure someone will part with one for a more sensible price. But check it out thoroughly first before changing the tank.

Steve

[hoops]

Thanks for the detailed reply, I have today cleaned out all the lines and carbs forward of the fuel filter and will give it another go tomorrow.

I managed to grab a quick video of the spluttering, it runs fine and then this kicks in.

https://www.youtube.com/watch?v=Hv6-2tuX4oE