Please help... he won't start :(

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radioactiveman
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Re: Please help... he won't start :(

Post by radioactiveman »

Thank you. I will keep an eye on that.

I wonder if this could be the root of all of my running troubles :-? Clearly the issue has got worse as the fuel is now very obviously leaking, hmmm. It’s doubly annoying considering how expensive it is :lol:

Should I take any other precautions before messing with the fuel system (such as removing the battery)?
Wearytraveller
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Re: Please help... he won't start :(

Post by Wearytraveller »

As mentioned, it probably is the cause- a punctured float or malfunctioning needle valve will cause the mixture to be overly rich, either constantly or intermittently and altering the mixture setting and idle speed will never compensate for it.

Yes a bit of a pain financially, but well worth doing. The 'stay up' floats and viton tipped needle valves are good items, I've had 13 years of heavy and hard use from these items with no sign of degredation or wear. Think of it as a sound investment for reliability!

Burlen fuel systems hold the manufacturing rights to new SU carbs and spares, they do a kit with float and needle jet/seat at a good price, it is out of stock at the moment but might be worth giving them a ring?
https://sucarb.co.uk/float-chambers-spa ... valve.html
Other places may have stock of these items if not, but I'm not sure if there are cheap and possibly suspect copies of these items out there, probably worth checking you're buying good stuff made by Burlen.

General advice is to disconnect the battery earth lead before working on the car (this is the safest one to disconnect, think about it, if the spanner then touches the battery clamp or body in the process, there is no short circuit). Granted, you won't be doing anything electrical or working near the battery, but it's a sensible precaution to get into the habit of, there is then no way you (or anyone else) can absently mindedly operate any switches/motors which may spark and ignite the petrol vapour. Other precautions- check and double check your work (did you tighten the hose clips properly?) And once all is fixed, pull over and check a few times that there are no leaks and all is well.

It's worth taking all this seriously. I once bought a set of 5 wire wheels for my MGB from ebay- they were advertised as a full set, with spare, but one damaged. On collection the damaged wheel was heat and smoke blackened. Chatting to the owner, it turned out the car they came from, having a pair of similar but larger SU carbs, had the same problem as yours with one overflowing. It suddenly started running roughly, and before the owner could pull over and switch off to investigate, it backfired through the carb setting the whole thing ablaze, only a few parts were worth salvaging afterwards.

Kind regards, Chris.
oliver90owner
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Re: Please help... he won't start :(

Post by oliver90owner »

they do a kit with float and needle jet/seat at a good price,

Over thirty quid for the single item likely required (if that, if it happens to be debris in the float valve or a leak around the float valve threads)? Both floats and float valves are usually very long-lived items, giving no trouble over decades of operation.

Do ascertain the fault before ordering unnecessary parts. It is the sensible way of doing things.

Also, does that thirty quid include shipping?

Avoiding electrical sparks, particularly with volatile flammable gases around, is always a sensible option for the uninitiated. Even sparks generated by, say, steel against steel can be a hazard. I once asked for some brass or aluminium measuring bushes for a cartridge reloader powder dispenser. The machinist had to make them twice because he ignored my specification (for non-ferrous metals) and made them in steel. There could have been as much as 400g of Nobel smokeless powder, just waiting for a spark to ignite it!

After reading the recent responses, I am now wodering if wearytraveller either works for the supplier or has shares in the company!🙂
Wearytraveller
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Re: Please help... he won't start :(

Post by Wearytraveller »

Not sure from the wording if you're suggesting I'm advising throwing money around without a structured fault finding process first, or reinforcing what I have already mentioned, sorry. But if as you say, you read my previous post (Sun Apr 24, 2022 7:38 pm) you'll note I gave instructions for checking the float and the needle valve/seat, and advice to replace either if found to be at fault. At no point did I suggest any purchase without testing, in fact the exact opposite.

The original poster gave a link to a float only for £28.70, I answered his question that it was the correct part. Further to this I supplied a link to a package including both but did not stipulate he needed both. I note ESM, a popular suppplier with members of this forum (no connection to the company and in fact I've never used them) sell the float only for £22.78 plus £3.54 postage. They don't list the needle valve and seat. By that reckoning £31.25 for both from Burlen looks a good call, although they don't list postage charges so the original poster would have to check. I also mentioned other suppliers may stock these items (but proceed with caution if non-genuine), anybody is welcome to shop around, never my intention to become a personal shopper! (Actually I'll be in the market for these parts soon, I have several spare carbs to overhaul then sell. A quick look around seems to show that all that seems to be available at the moment in the float line are Burlen's 'stay-up' floats, so they'll be profitting regardless of where you buy. There seems to be an aftermarket needle valve and seat available for about the same price as Burlen's, I know where I would put my money).

As Burlen are now effectively the SU carb company, their parts are generally regarded as the best available in the circles I move in at least, in my experience it is uncommon to find other dealers selling their parts for less although bargains may often be had with some time investment. There is a risk that non-Burlen parts lack quality control and I would not personally recommend such.

In the few posts I've made on here I've sung the praises of GKN propshaft parts, Gates fuel hose and Distributor Doctor ignition components. Along with Burlen SU bits, I've had excellent service and reliability from products from these companies, views shared by the majority of the classic car movement, and so I recommend to others. I never thought I'd have to give a disclaimer on the internet while offering advice to somebody obviously learning the ropes, but nope, I've never worked for anybody other than myself apart from a brief and enjoyable lottery funded stint at a museum, and as for shares, no real idea what they are or how it all works, and not fussed either, I put my money in old tat and try and stop it dissolving :lol:

Regards working with the fuel system, yes sparks from flicking a switch or steel on steel could be the cause of something nasty, and on the road a fuel leak under the bonnet won't be ignited by the manifold heat, but the resulting vapour may be set off by a stray spark from a badly maintained ignition system, or even flicking a switch on the dash if vapour finds its way into the cabin.

Scary error with the powder dispenser! Over the years I've seen a few bronze versions of common tools once used in explosive environments. My ultrasonic thickness tester is an 'intrinsically safe' model, as long as the operator remembers to change the batteries outside the danger zone :lol:

Kind regards, Chris.
radioactiveman
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Re: Please help... he won't start :(

Post by radioactiveman »

Again, my thanks for all the guidance and advice from everyone!

I come with an update... good news!

Over the weekend I replaced my fuel line and my current float setup with a ‘stay up’ float kit and a Viton needle/seat.

I also changed my oil and filter for good measure.

After this, the car started well and the choke was able to go all the way in after very little time at all. No fuel could be seen from the float area or the fuel line ends. I adjusted my idle so that the ignition light has just the hint of a glow.

I took him out for a brief jolly and all seemed well. No fuel smell and no drama. :D

AND not a jot or tittle of oil dripped from the sump whilst he was idling or on my return from my drive :tu1: :tu1:
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