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**20/07/21 Well, Well, Well ** Probably how not to restore a Herald!


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Somethings making duplicate posts Aidan youve managed 5

will drop a note to the mods

pete

 

do make sure any electronic unit does keep the output constant not just a dropper

the idea is to give the gauges a constant feed regardless of the charge or battery voltage variations you get in a drive.

 

Pete

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I can only see one post from Aidan but a load of duplicates from Casper, very weird.

 

Aidan that would make sense that they have replaced the bi-metallic strip with a solid state device, given how cheap the latter appear to be.

 

On the topic of earthing the speedo, I noticed last night that I have a black wire with no connector hanging freed from the loom behind the speedo.

 

Is this possibly the errant earth wire?

 

Karl

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Thanks for that Pete.

 

I have at least one other earth lead hanging loose behind the dash.

 

There were three at one point, but I worked out that one of them ought to be connected to the interior light fitting.

 

That should at least be an easy fix.

 

Karl

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Pete that is where a photo is worth a thousand words!

 

I managed to get the Herald started this afternoon, it's not a consistent starter, and doesn't want to idle particularly.

 

I've tried adjusting the idle speed and the mixture as per the workshop manual, but to no avail.

 

I think I might have to call in a professional to set the carb up properly.

 

Karl

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Take the slow running jet out and clean it , located half way up the carb body engine side

 

if the throttle is too open the idle circuit doesnt work and nothing will adjust

 

but if it fires with throttle open but dies at idle then suspect the slow run jet is blocked

They are a trunkated jet try not to poke the debris into the jet body

and it must seat in the carb body when screwed back in..

worth make sure all the small drillings in the top joint face and where they exit near the throttle plate

are clear.

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I'm having to start the car on full choke, and then push the choke back in immediately and then blip the throttle to keep it from stalling, which matches your description.

 

I checked all the other jets, and took the top off the carb to check the float chamber, all of which were clean and clear.

 

I would have checked the slow running jet if I'd known about.

 

Something for me to sort over the weekend.

 

Thanks

 

Karl

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In the body are some chambers that take air or fuel they terminate in the top face under the top cover and

exit as small holes near the throttle plate these control idle mixure and air flow and the vac take off

its easy with age these get blocked , if you are playing give them a blow though or a very careful prod with soft wire

 

some slow run jets are able to seperate , think webbers do , but yours will be a solid jet ofetn the crap stays inside it

 

make sure the choke flap is free, there is a small spring to allow air flow to let the flap open and chatter as

it cranks and fires,, give closed flap a poke with finger it should

open a little and self close

pete

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Thanks for the additional info.

This afternoon has been spent stripping down the carburettor and giving everything a good clean.

BlNy6W.jpg

Here we are with the top removed, and prior to removing various jets and cleaning them out with some of my airbrush cleaning brushes, which are bendy enough to go around the swan neck, but firm enough to dislodge any muck.

I can confirm the existence of both O-ring and ball bearing beneath the swan neck, and no I didn't lose them!

The slow running jet was removed, and had the tiniest sliver of muck hanging out of the nozzle, which was gently removed.

The jets then all got a blow through with air from my airbrush compressor, with the pressure set to 90.

With everything clean I reassembled the carb, and put it back on the manifold.

Truth time, would it start?

Yes!!!!

Not only that it kept running!

I had a play with the idle speed and the volume control screw, and it now idles beautifully.

Next challenge, take it out for a spin.

Fine up to about 35, then it starts to pop and bang and feel like it's running on 3 cylinders.

I need to check the plugs to see if aren't firing properly, if they are all OK, then I'm assuming a timing fault or the points.

Any advice gratefully received, as it has been invaluable to date.

Karl

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Its brilliant when the simple things solve a major hic up and diy has saved you being fleeced

 

you've had previous plug trouble, are these new or used, plugs life and soul of the engine

 

the oiling may be due to none starts or crap old contaminated fuel

 

someone in the past tops up with fuel from a can with oil in it and problems persist for ages

 

old trick cook the plugs blow lamp or oven and fit them hot .

 

but fit new so in known state , is better than trying plugs that only look like a plug but wont perform like one

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Pete, these plugs are new NGKs so should be OK.

 

One of the old ones I removed cracked in half on removal!

 

I gave all the plugs a good clean up with a soft wire brush after the run this afternoon, and 1 & 4 were muckier than 2 & 3.

 

Not sure what to make of that.

 

Karl

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Guess thats down to the manifold and the split airway in the head

have you done a compression test , tappets all got a gap? 0.010"

 

as this is a downdraft carb is the manifold drain tube ok , it should have a restricted jet like end

so a little air will be sucked in but it drains excess fuel from any flooding and poor starts on choke

including any perculation from the jetting when switched off .

 

the car sounds like it needs a good long cruise to clear it all out, if you get it to run that long

pete

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Tappets will be one of next stops alongside the timing.

 

The rocker cover hasn't been removed in a while as it is practically welded on, so it's anyone's guess when the tappets were last set.

 

I'll need to take the rocker cover off to check the timing, so might as well learn about checking tappets at the same time!

 

Thanks

 

Karl

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you dont really need to seal the gasket , some glue the thing and yes its cemented in place, thn ge tin cover and gasket face are not the best design

with little gasket location /retention abilities

if you put a alloy cover on your Easter wish list get a club   neoprene everlasting gasket to go with it and whilst removal is not a monthly check it will not leak and will pop off 

'just like that'  

 

im often in your area as sister lives in Bloxham,  if you get stuck   shout !!

 

maybe in the spring i can arrange some more training days   for any visitors  to sunny luton

 

pete

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Not had a chance to do anything major today, however I did exhume the 'old' plugs, well 3 of them at least as the 4th had broken in half!

These were then thoroughly cleaned, first with a wire brush, and then with cellulose thinners on a cotton bud and kitchen towel.

Here we are with 2 out of 3 cleaned.

knqdGi.jpg

You can see how mucky these were getting.

After clean up, these were re-installed, and one of the in situ plugs given the same clean up treatment.

Before firing up, I slackened off the mixture using the screw on the bottom left hand side of the carb, which should hopefully stop the fowling of the plugs.

I'm pleased to report that she started on the button!

Next up will be a replacement air filter, as the current one is very grubby, which probably doesn't help much either according to the Haynes manual.

If the weather is half decent tomorrow, I'll try taking her out for a spin.

Karl

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The mixture is only adjustable by the idle circuit, you cannot make any changes to the main normal running thats controlled by the jetting.

once you open the throttle plate a little the idle circuit ceases to operate, that why a fast idle will not give any changes in mixture adjustment to the tapered screw.

 

the choke flap on some you can alter the automacity spring to give more flap load or less , a sort of winter summer setting , normally wind the small spring over some ratchet teeth on the flap lever

The flap must be free to chatter open a bit as each piston sucks , it should open the flap when you rev up a bit

 

The mixture screw wants to be set to best idle amd then screwed in to drop the rpm by about 50

so you are just at the weak side of best , not the rich side of best

 

pete

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  • Bordfunker changed the title to **20/07/21 Well, Well, Well ** Probably how not to restore a Herald!

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