1983 Golf MK1 1.8 DX GTI - Bosch Distributor Springs...

Discussion in '8-valve' started by Zender Z20, Dec 16, 2022.

  1. Zender Z20

    Zender Z20 Paid Member Paid Member

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    Thanks for trying, it's appreciated.

    I've now a (short) list of dizzies that have the same Hall sender as the one I was after, but none that also have the same vac. canister.

    I've tried taking the trigger wheel off a spare dizzy and it's no where near as easy as it's made to sound, specially on something that's 35-40 years old.

    If I'd an old one to sacrifice I'd keep going, but as I don't have that luxury I've not gone any further.

    Upshot is changing the cannister is simplicity by comparison and I think that's the way to go, but that's assuming your existing canister works or you can find another.

    The one I mentioned above might've been added to the list, but the centrifugal advance is an unknown and because you're using the shaft and its attached gubbins it'd need to be the same.

    The vac. canisters are another thing being re-manufactured and sold as covering a wide range of applications... no expert, but struggling to see how that can work as the specs. are quite different from engine to engine.
     
  2. rubjonny

    rubjonny Administrator Staff Member Admin

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    yeah the wheel isnt easy to shift, unless you have the proper tool. you'll probably end up bending it trying to remove. easier to pull the entire shaft if its all in bits
     
  3. Zender Z20

    Zender Z20 Paid Member Paid Member

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    Spent an hour or so cleaning a replacement distributor I've since got, it's not the original 026 905 205 H of the car which was proving difficult to track down (in the UK at any rate, more were being advertised overseas), but 026 905 206 A which showed up on RJ's chart as having the same Hall sender, though wrong vac. canister.

    With the exception of those unique dizzy numbers on the housing assembly and different vac. canister, they appear to be identical in every other way.

    All their various component pieces, inc. more numbers inside the housings themselves match up on both dizzies.

    A number I didn't notice before is the one in the second image below... it's pressed into the base plate assembly that carries the centrifugal weights / springs / arms etc. as a separate unit

    As the Hall sender parts are on a different plate above it, I'm guessing each was a standalone item as far as Bosch were concerned, hence them giving both a number of their own.

    It's looking increasing like the 3 digit number pressed into the trigger wheel is it's unique identifier, they match on this pair.

    As these appear to differ from application to application, it's an important (and easily seen) way of confirming you've a potential match to your existing trigger wheel.

    As RJ says above... the separate plastic / electrical Hall sender parts seem to be the same component regardless of which dizzy they're in, it's when they're combined with a particular trigger wheel that the different spec. occurs.

    I don't have more dizzies to compare to, but it wouldn't surprise me to find the number on the base plate identifies the spec. chart of the centrifugal advance, in the same way the number on the vac. canister differentiates one of those from another.

    Any lists I've seen so far unfortunately don't go that deep down in their detail to identify what particular centrifugal base plate is fitted, the best they do is quote the Hall sender assembly as one unit.

    Up to now I was assuming the Hall sender assembly number, in a roundabout way, also identified the centrifugal advance spec., but it's possible that's no longer the case if Hall sender and base plate can potentially be mixed and matched... I just can't confirm or deny it at the moment so something to be aware of.

    From what I've found on this admittedly small sample is it's entirely possible to make up a particular dizzy from the parts of others and keep to it's correct spec. at the same time.

    The crux will be finding out what the part numbers are to allow you to source which dizzie has what combination of components inside it and that doesn't look like it's going to be easy.


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  4. rubjonny

    rubjonny Administrator Staff Member Admin

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    Good info :) On a side note, 026905205A and H look to be the same apart from the fact A has a rev limiter arm and H has a solid arm plus the hall sensor plug is early vs late. it could be possible to extract the vac package from the A and drop into the H, at the same time swapping the early hall sensor for the late one to get you back to OE spec...
     
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  5. Zender Z20

    Zender Z20 Paid Member Paid Member

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    Yup... it can get very complicated, very quick when you start looking more deeply into them.

    You touched on it in an earlier post and it's right that something as simple as one small change, like moving from the oval Hall sender connection to the rectangular causes a change in the complete dizzy part number.

    The vac. cannister spec. charts you posted earlier... I was looking into how you could measure them.

    Primarily to check they're still working within spec. but maybe help to physically identify suitable ones that I can't get the written specs. for.

    Trouble is they seem to operate at such a low vacuum most regular gauges aren't accuate enough for them to register it.

    The differences are as small as 15 mmHg between different start / end points / different canisters so must be miniscule, yet they have to affect the engines correct running other wise why go to the trouble of manufacturing them?

    Big subject dizzies, maybe foolishly seems to get overlooked nowadays.
     
  6. Zender Z20

    Zender Z20 Paid Member Paid Member

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    Few weeks before we'd begun to think the electronic portion of the Hall sender was for want of a better word 'universal', and it was the trigger wheel that made the difference, found this replacement kit which has just arrived today... and sure enough the wheel has 063 stamped on it like the others that are listed as suitable for my dizzy.

    Comes with everything you'd need right down to the little 2mm dowel that stops the trigger wheel slipping on the main shaft.

    There's further numbers cast on most of the plastic parts that make up the Hall sender assembly and they just seem to identify the individual pieces ie. cover or connector for example, so again probably universal or semi-universal.

    One number that is on the new sender (probably because it hasn't had a chance to wear off maybe?) and not the others is 294.7216MS2

    Can't track that down at the moment either, pity as it might've help clinch it.

    Still can't confirm this unfortunately but if your Hall sender does pack up it's possible you might be able to get a replacement from a dizzy other than one the same as your own if you're also able to re-use your existing trigger wheel.

    Took apart the cheapie spare dizzy from he XR2 today, quite a bit different, specially the Hall sender side of things.

    Useful to do, though didn't bother with piccies... quite a few mickey mouse parts scavenged like screws, washers, centrifugal springs, that tiny dowel and such, but not much else unfortunately.



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  7. Cressa Paid Member Paid Member

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    I shall try and dig my my distributor out later and post you some pics. I wish I had your patience and attention to detail, as the info you show us is on another level.
     
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  8. Zender Z20

    Zender Z20 Paid Member Paid Member

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    This sort of mechanical stuff fascinates me, I'm continually being massively impressed by how decades ago they worked out reliable, accurate, and analogue ways of doing such complex tasks.

    Trouble is it's all 100% alien to me, never had any dealings with engines until about 2 years ago and even now it's still limited to the 2 x Golfs... to say I'm scratching the surface is an overstatement.

    Not many regrets in life, but one's not following a trade / profession that involved some sort of mechanics, have a great respect for anyone who has and envious of their knowledge and abilities.

    It's more that I'm time rich than have more patience than anyone else.

    Great site this for just rolling ideas and thoughts about, quite often I'm on the wrong track and need advice, but no shortage of that here plus no one seems to get too shirty when you ramble on - well not in public anyway.

    Good too that occasionally I get the chance to repay with something, even it is small.

    Hard info's difficult to get on these dizzies, relying on bits'n'pieces I find, so yes it would be good to see yours, specially since it's possibly one of the ones RJ has highlighted.
     
  9. Cressa Paid Member Paid Member

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    Couldn't find it today, which is slightly worrying but must be somewhere. I was even given a spare with the car but no idea if they are the same. I do know mine is a little worse for wear, broken at the plastic connector and extremely worn where the clamp fitted.
    I look forward to having the extra knowledge when I dig it out. I always prefer to refurb and dont fancy the price of a new Bosch, even if available. Then I see ones on Ebay for £40 and wonder what quality they really are....
     
  10. Zender Z20

    Zender Z20 Paid Member Paid Member

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    No experience of the repro. ones, but definitely seem very inexpensive.

    Would genuinely be interested in hearing more about them from some of the places selling them... still not convinced how they can claim they properly suit the range of different vehicles that they say they do?
     
  11. Zender Z20

    Zender Z20 Paid Member Paid Member

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    Small update - last week I emailed what appears to be one of the bigger companies who are selling the repro. dizzies and canisters in the UK.

    In fairness they are the only ones whose site goes as far as listing which particular canister suits which dizzie, even cross referencing to the correct VW and Bosch numbers.

    Simply asked them to provide the vacuum advance start and end pressures for their repro... a bit like asking someone what capacity engine's in a car, it's that rudimentary a question.

    Unfortunately no response so far, will update when they do.
     
  12. Zender Z20

    Zender Z20 Paid Member Paid Member

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    No reply from that outfit, not expecting one now so have to assume they either couldn't be arsed or just don't know (which is more worrying saying as they're selling them to unsuspecting punters).

    One for @rubjonny - the advance chart you posted before and shown again below.

    The vacuum advance part only, the mmHg figures for 026 905 205A are -

    'Begins' - 45 90 mmHg

    Presuming the figures below are for 'Ends' even though it doesn't say?

    If so they're 180 195 mmHg

    Is your reading of those numbers that they are denoting a range ie. 45 to 90 and 180 to 195?

    Reason I ask is I've got my hands on a vacuum gauge and if things are as they are starting to seem may just be able to get the specs. for unknown units simply through testing.

    vac. chart.jpg
     
  13. rubjonny

    rubjonny Administrator Staff Member Admin

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    if you look at the other charts they do say 'ends' for the lower column so pretty sure you're right yep

    presumably it begins at +0 degrees at the low end of the chart up to +17 at the max value, going by what it says under the rpm advance section...?
     
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  14. Zender Z20

    Zender Z20 Paid Member Paid Member

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    Cheers... would make sense that they are a vacuum range between which you're going to be in spec.

    The amounts involved are so low it'd be amazing if they could calibrate a simple diaphram to accurately get exactly 45 mmHg for example.

    The vacuums are only registering on the first portion of a regular gauge, in itself making it difficult to get a precise reading, but having a range to fall between more than compensates, makes it accurate / doable.

    Had a quick go off the cuff at it. Two of the three canisters I have (from VW dizzies listed in your chart) are coming up within the spec. ranges quoted.

    The last canister is from the XR2 guniea pig so it's specs. are unknown to check against, but it too is coming in around the same range as the VW's, infact it may even be so close to one of them as to be a good substitute.

    Want to sit down and properly check again before commiting to anything though.
     
  15. Zender Z20

    Zender Z20 Paid Member Paid Member

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    OK... checked the three vac. canisters over and over again and they're all giving pretty consistant readings.

    Just to make life more awkard than it needs to be the gauge I got reads in inches/Hg and kPa, while RJ's chart is in mmHg (I've just ignored Bar), so to save me converting everything everytime, I've hand written in the kPa specs. that you can see in the image below, ignore the rest.

    ... and the 2 x VW ones are both within the quoted ranges, though admittedly each is at the very top reaches for their end readings.

    A pity, but the XR2 canister just falls outside matching either of the VW's, though not all that far off for one of them (ironically the one that's of no use to me).

    Just goes to show that these canisters are definitely set up to work differently, hence them having a unique number and because the amounts they vary by are so small it's hard to see how the reproduction ones can claim to suit specific applications when they also claim to span so many different dizzys.


    Vac. Readings.jpg
     
  16. Zender Z20

    Zender Z20 Paid Member Paid Member

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  17. Cressa Paid Member Paid Member

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    Not yet mate. It is on my list, but had to put my time into finding a way to replace the brake vacuum T valve belonging to Mk1 parts, but obsolete.....
    I will have a better look this weekend, but am on nights too. Zzzzzzz
     

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  18. Zender Z20

    Zender Z20 Paid Member Paid Member

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    No worries, used to do nights off and on for years... Don't envy you!
     
  19. Cressa Paid Member Paid Member

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    I don't enjoy them unless we are busy. Had a look for the distributor again today, but no joy. This is messing with my head
     
  20. Zender Z20

    Zender Z20 Paid Member Paid Member

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    Haven't let this go, still been plugging away!

    Picked up a cheap VW tool for taking the trigger wheels off, bit nerve wracking first time saying as I can't afford to damage anything and it just looks like it'd bend the metal.

    Thankfully not as the wheel itself isn't pressed on in the way a bearing would be. Yes, it's a tight enough fit but took surprisingly little effort to pull it up once started, think the years of grime had semi-stuck it in place.

    I can see how Bentey / Haynes etc. say it can be removed by using 2 x screwdrivers to prise it off (but rather you than me though).

    I'd the shafts and innards already out of the distributor housing so can't say this for certain, but it's likely the tool will take the wheel off even they're not, the legs can swivel and adjust so should slip into the gaps.

    Bits are laid out below, the tiny little dowel doesn't need to be removed before the wheel, it stays in situ in the shafts groove as the rest rises up.

    The tool is VW 3163, this one cost me €20 but as usual there's folk out there who think they're gold plated and charging accordingly.

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