K-jet metering head strip down and rebuild thread

I am trying to strip the air flow metering section . As the flap pivots on a pin section I am trying to remove these so that I can strip the whole lot down. Either side of the outer frame are
A circlip - blanking disc - bearing - spring.. then what looks like a pin. This is what I am trying to slide out of each side. Or is it squashed in by the counterbalance weight which has a screw that is insanely TIGHT.
Has anyone EVER managed to undo this screw or take this piece apart?
Isaac, how is yours going?

 

Unless (like me) you're taking it apart to that extent simply because you enjoy tinkering / seeing how it works I'd recommend leaving well alone.

There's no real advantage going further than you already have as it can be cleaned just as well with the arm etc. still in situ.

One reason you might need to remove the arm is if the adjustment screw has rounded out / needs replaced.

Below are photos of a spare I disassembled and you're right the brass coloured screw that passes through the counter weight acts on the pin by squeezing it tight.

Rightly or wrongly I found a small amount of leverage in the arms gap (once the screw / counterweight where slackened off) opened it enough to get the pin out.

Be aware though, in my experience it's still a tight squeeze and it wont just fall or push out easily, plus getting it all to line up again later is a faff.

I went the distance with the spare as it's adjustment screw needed replaced, it's one of those jobs that you need two pairs of hands to do, in itself not difficult but everything wants to pop out and fights against you unless you get it just right... lots of patience needed.

Interesting that your air flow is the same part number as mine on the MK1 ( 049 133 356AA)

If you are able it'd be usefull if you record any other part numbers you find before reassembly, could identify cross over bits from other cars if spares are needed.

On that score, from what I can see there's quite a few common parts in these, the adjustment screw is a good example.

What appears to differentiate one complete unit from another (over and above the shape / dimensions of the coned intake) is the profile of that pivoting arm.

That little roller is what the plunger from the fuel meter rests on and the travel of it's arc differs from one application to another depending on where it's sited.

The pin in the second from last image and that contoured spring affair in the last image are further ways of adjusting the settings.

 

Unless (like me) you're taking it apart to that extent simply because you enjoy tinkering / seeing how it works I'd recommend leaving well alone.
Exactly that mate. I like the learning process and how it works. Also allows me to check all the components.
I intend on cleaning the outside/ may take it for media blasting so could really do with it apart.
That adjusting screw is a masterpiece.
Do you have a picture of the plug that is supposed to be on top of the tube for the adjusting screw. I am missing one, so may see what will fit.
Great news is that the seal kit for the fuel regulator that i ordered 2 days ago was delivered today. So I am making the most of my time

 

The pictures are a great help, thank you. I have managed to undo the worlds tightest screw, just need the pin out

 

Cut'n'paste from my Zender thread (what do you mean you haven't read it!) -


"The adjustment tube on the air-flow sensor body... never gave it much thought 'till started getting interested in K-jet. and now know there should be a 'plug' for it when not in use.

Anyhow turns out there's 2x types, not sure the reason for that but ones a blue bung affair in the style of that on a MK2 air flow meter. I'm guessing also like the MK2's it would need replacing every time it's removed because of the way it's pressed in and sacrificed when getting it out.

The other's like the one below with an handle.

Surprised me to find they're still available (source seems to be VW Classic Parts, so also some re-sellers).

https://www.ebay.co.uk/itm/133005229602

If you think £15.00 is steep, have a look out for the specialist Porsche sites flogging the exact same thing for two and three times the cost, amazing!

Kept thinking that it reminds me of something and eventual the penny dropped... the daubers you use to apply dye to leather (Google / eBay search 'Feibings wool dauber').

The tube inner diameter is 7mm which just so happens to be one of the sizes rubber cord seems to come in.

No need to explain what I've done just look at the piccies. The 'real' bung is probably bonded to the metal, I've just bent over and splayed out the dauber shaft so it doesn't pull off trying to get it out.

Rubber pipe was £3.00 and some pence posted for a metre (one of those things that'll go in the bits'n'bobs box to save the day again on other jobs), the dauber I had, but again if you buy in quantity cost buttons each."


Real deal in the first 3 x images...







My counterfeit design...










Only piccie I've found to date of a genuine one in place...

 

I keep forgetting you're a MK2... just speculating here, but perhaps the blue one is more correct to the later car?

Here it is on eBay -

https://www.ebay.co.uk/itm/13300523...rCs|ampid:PL_CLK|clp:2047675&epid=13012484941



The adjument tube it goes into on my air flow sensor is right up against the body of the fuel distributer, that lack of room might be why it's bunged by something that inserts into it rather than over the top as a cap would?

Hard to tell if the blue one is a bung or a cap - maybe relevant that it's the same colour as the bung on later digifant air flow meters, could be one's an evolution of the other?

 

I have read your Zender thread, a mass of information. My brain can only remember so much I like the pin and plug that you made. When this is back together I shall have to see what I can make

 

Just winding you up, you're probably the only one reads it... was trying to see what the 3 x numbers embossed on your air flow sensor plate are.

Looks like 5** ?

That would date it's manufacture to 1985 which suggests it's original to the car, if you can post the last two could work out the month too.

 

It looks like 551..
I've put more pictures of part numbers for you have a look at. I did take the pivot arm off to help me clean parts and the Allen screw as it was especially caked in grime and muck. So much so that an alien key couldn't fit in!! So I will source some type of bung
I am just looking at the hose from the airbox and can't work out its number to see if I can replace it. Be interesting if it is a mk1 part.
Mine is an 86 registered and the car looks like it was never tampered with in anyway, just left to ruin.

 

551 would be November '85.

Don't have the pipe handy, but probable any markings are long gone by now anyhow.

All the other numbers tally with mine, which makes sense if they're both 049 133 353AA... so in a sense it is a MK1 part, if only by virtue of it having been in use since at least 1983.

I know it's not always easy, specially working with lots of parts but if you're able photo's of you refurb'ing the fuel distributor would be as equally interesting / useful.

Did look into it in some detail, but that was months ago so need to refresh... who did you use for the kit, think there's more than one source now?

 

I gave the fuel regulator a coat of paint whilst doing other things. Salvox, the USA kit is what I purchased, I think that is what you had. I shall start splitting it very soon

 

Well I went for it this evening and opened up the fuel regulator/distributor. What is its proper name?
Lots of pictures taken and unfortunately this 8v is different to a 16v that I had watched on you tube.... I am stuck on how or if the centre fuel unit comes out. Looks like something from a star wars death star. So i shall have it tonight more obvious in the last 4 pictures (picture heavy)

 

Great 8v thread

 

As said, I need to refresh myself on what I read months ago so please double check everything first.

I'd an old Volvo fuel distributor to use as a guinea pig... despite looking OK on the outside, it was rotten inside with rust... maybe some of the commercial refurb. sites can bring them back from the dead but to the rest of us mere mortals apparently they're scrap if the inner surfaces aren't 100% blemish free.

Also high lighted that alot of the individual components had despite looking superficially the same very subtle differences, such as profiles.

Probably means there's not much that's interchangable.

I'd the reverse issue from you, I stuggled to get the plunger out of the top half.

The pics below should hopefully show whats hidden of the plunger below the line of the lower halfs surface face.

Unless there's something unusual, should pull out if you can overcome the resistance of the larger rubber 'O' ring.

I took the gauze filter off, it's a tight squeeze to slide on/off and those circlip affairs are a pig to take off/on. Big risk of crushing or ripping the filter.

 

Probably just not in your photos, so please ignore if you've aready done it.

Below those 4 x hex plug caps on the top side of the upper half are screw in plugs - handily the same 3mm hex as the adjustment screw on the air flow sensor.

From recollection they're factory set and help to regulate the flow or pressure to each injector (or something along those lines), anyhow there's 'O' rings that may need replaced. Mine were definitely hardened up.

You'll have to re-calibrate them if interfered with but there's instructions out there.





The primary pressure regulator in your piccies doesn't show the last piece at it's end, again ignore me if it's done but if not may still be at the bottom of the port it sits in?

Adding / removing or changing the width of the smaller shim / washer is also a way of regulating pressure if required. Nearly sure I've seen selections of sizes being remanufactured.



There's apparently another bit inside the primary pressure regulator, accessible via the hex socket in it's end - may even be third 'O' ring in your kit for it - but the Golf's (and the spare Volvo one) are so tight I'm not going to risk it.

 

Ha! Should've watched the vid. first, saved me a bit of typing!

Very useful, a good reference for double checking orientation / fit of parts on another distributor matches your own. In a 30-40 year old car you never know who's been there before you and no guarantee they did it right so you end up putting something back the wrong way for a second time.

 

Ha,I did find that as it fell out when I turned the body. I did take out 1 of the pressure regulator Allen screws, marking the no. Of turns and my seals were still okay. So I am leaving the others as my kit didnt come with seals for this. Couple of queries...
1. My centre plunger underneath seems very slow so I wondered if a replacement spring was available. Or does it have more oomph behind it when it has fuel and pressure? It is only a small thin spring I suppose.
2. Now I know you said don't take out the hinge pin on the aiarflap part..... i cant find one of the damned springs ! I have even been and emptied the dustbin, searching with a magnet. It's got to be somewhere
If nothing else, I feel happy that I have done the fuel rebuild part, quite satisfying. I just hope it works
I did find down the injector ports 4 x tiny cone shape filters that had a clean.. Although I didnt take the filter gauze out of the central piece. As you say it looks fragile
Thanks for your help with this

 

Definitely replacement springs available, noticed one seller on eBay had them in the last few days.

All vague now but yes I think you're right that the fuel pressure does assist the plunger to move downwards... only speculating, perhaps the spring dampens rebound as the arm continually rises and falls with the air flow?

Nearly sure there was no similar spring in the Volvo distributor, must hoke it out again and go through what's left.

There's just the one spring / two ball bearings / two discs / two 'O' rings and two circlips holding the pivot bar in place.

Never gave it much thought as to why 'till you mentioned it. Only thing I can think of is the air flow meter casting is thicker on one side than the other. Not sure if it's uneven to accomodate the spring or the spring is there to accomodate the uneveness, if you know what I mean? The spring goes into the longer of the two entrances, so perhaps is compensating / self regulating the bars position some how?

 

Having one spring has saved me a huge headache, thanks. I couldn't remember seeing a 2nd but assumed there would be one either side and I had misplaced it
Call off the search party.....

 

I've held off getting a refurb. kit 'till I'm 100% certain I know what I need, and they're all expensive no matter who you get them from so might help save me something.

This is an image from one that's been in my eBay watch list for a while, but it's starting to look more and more it's what I'm after.

Useful too to see what they think might need replaced (though probably covers more than one specific car and some are possibly redundant on the MK1 and 2 perhaps?).



You mention not changing filters at the injectors in an earlier post... had you done, are these what you mean?



I've yet to find those somewhere obvious on the MK1, may be a later MK2 thing... if not are they at the bottom of these ports on the top of the fuel distributor?

There's something lurking in there, but it's not that clear to the eye or in the images. I don't want to start prodding around and damage something unrelated just on the off chance there is something in there to change, would prefer to know for certain first.