timeing

[tomas.geoghegan]

Hi Can i have a bit of advice please.
I messed about with the distribitor and set the timeing by sound of engine.
i drove Ok for along time. when my car went for its mot i asked the garage to set my timeing up with a strobe to get it dead right. after that is now running like a dream could not be happier . But when i start it from cold it pops and bangs a little bit until it gets a little warmer then perfect! ( is that normal ?
Thanks Tom Moggie Geoghegan

[bmcecosse]

How would they set it 'with a strobe' - what would they set it to? The original settings quoted in manuals etc were only ever guide lines - and today's petrol is a very different beast anyway. The only way to set it now is to keep advancing until you hear a little pinking - and then retard it slightly....... It is however well worth while checking if the vacuum advance unit is working as it should........

[tomas.geoghegan]

Thanks BMC
Do you turn the dissy clockwise for advance and anticlockwise for retard?
And how do i know if the vacuume advance unit is working?
Many Thanks
Tom Geoghegan

[bmcecosse]

Clockwise to advance - tiny bit at a time. For vacuum - take the cap off - disconnect the pipe at the carb and suck it. You should be able to pull a vacuum, and the dizzy top plate should move and relax as you release the vacuum. If no vacuum - or no movement - then the vacuum advance is u/s.

[tomas.geoghegan]

Thanks again for top advice.
Will have ago at it tomorrow.
And will keep you posted.
Best Regards Tom

[tomas.geoghegan]

Hi BMC
Could you help Please.
Iv checked the vacume unit by sucking the pipe and there is no movemant or vacume atall.
Do i order a new vacume unit ? is it seperate from the distributor? and is it easy to fit?
Thanks
Regards Tom

[bmcecosse]

So - I ask again - how on earth did the so called 'garage' set this up if the vacuum unit isn't working?? Yes - the vacuum unit is easily enough changed - need to know what type of dizzy you have - 25D or 45D ? Unless it has been upgraded - it will be a 25D. It won't cost much more to get a complete NEW dizzy from simonbbc or accuspark. They sell them with points or with electronic upgrade. Personally I would go with points. If buying a NEW dizzy -the 45D type is the later design and that's what i would get.
This one is suitable http://www.simonbbc.com/distributors/4c ... istributor
or this one if you want to go electronic - car needs to be -ve earth! http://www.simonbbc.com/distributors/4c ... ermax-mini

[Neil MG]

You can get a new vacuum unit from the usual suppliers (£16.95 plut VAT and delivery from ESM). It's not difficult to fit, but very fiddly to do in situ. The most difficult part is removing and refitting (without losing!) the small clip next to the fine adjustment nut.

[tomas.geoghegan]

Thanks Neil For Your Friendly Advice.
But I think i will go for a New Distributer.
Best Regards Tom
Thanks Again

[Alec]

Hello Tom,

BMCE and I have had a few discussions about distributors on this forum, and again I have to disagree.
From the website link quoted:-

Here is our Lucas type 45D4 points distributor which replaces 25D distributors and fits:

Land Rovers 2.25 & 2.5
Sprite
Mini 850 1,000 1100 cc
Austin 1300 etc
MG MGB & MGB GT
Maxi
Allegro

My point is , yes they will fit but the specifications for such a range of vehicles quoted will be vastly different.
I would suggest asking for the specification, a Minor distributor should have a vacuum module with 8 degrees total advance and a mechanical advance of 18 degrees.

Alec

[bmcecosse]

18 degrees mechanical is far too much. That would be 36 degrees total assuming absolutely NO static advance. Even highly modified A series only need 36 degrees total advance - 15 degrees dizzy advance would be more likely - allowing ~ 2 to 4 degrees static advance to fine tune it for 'not quite pinking'....... Most old dizzies I have opened up have 11 or sometimes 13 degrees advance stamped on the bob weight - easily increased of course by taking a little off the nose with a hacksaw! But indeed - it would be interesting to know what advance these new dizzies come with - they 'may' tailor them to the different applications, although (like Alec) I rather doubt it!

[tomas.geoghegan]

Hi Alec Thanks for your take on this.
I have ordered a new ORIGINAL 25d points disributer not the later 45D (for a straight forward fit.
I notice on the vacume unit there is a adjuster nut. What would i adjust that Too?
Thanks Tom

[tomas.geoghegan]

THANKS BMC FOR GREAT ADVICE THOUGH
A NEW DISSY IS ON ITS WAY
CHEERS TOM

[tomas.geoghegan]

Hi Bmc Im asking the same question about these garages
Thay evan fed me a line that they had trouble finding the strobe .Yeh Right.!
Its so had to find a garage that really knows what they are doing. these days. And Understands old vehicles. Thave cost me a fortune over the last few years But unfortunately need that MOT
Best regards Tom

[Alec]

Hello BMCe,

that is the workshop manual figure. You refer to tuned Minis, but bear in mind the better head shape will probably give a quicker combustion time, higher specification engines don't necessarily require more advance, often the reverse is true.

Alec

[Neil MG]

The adjusting nut should be set to the middle position initially and then you set the timing by turning the distributor. Fine adjustments can then be made with the adjusting nut.

If your car is running well then it might be helpful to note the static timing so you can set the new distributor to the same setting, or a degree or two advanced of that setting. If you get it right you might be able to get it to pink and back it off slightly with the adjusting nut. If not or if you start to get to the end of adjustment then turn the distributor slightly.

[tomas.geoghegan]

Thanks Neil Very Handy information.
Best Regards Tom

[bmcecosse]

I've never found a dizzy with 18 degrees advance ! The current dizzy setting is absolutely useless - since it was 'set' with a knackered vacuum unit - and so will be horribly advanced to compensate...........
36 degrees total advance is pretty much the ideal total advance for a highly modified A series...... I've never heard of a more normal engine being set much above 30 degrees total. Higher compression requires more advance .......

[Alec]

Hello BMCE,

there is no argument that the distributor is below it's best, and needs work or replacement. All I am saying that the one fits all approach doesn't give the best result.
Having done a little cross referencing, Holden sell new distributors for the Morris Minor , and list three different versions (8 or 9 for the Mini incidentally) but the specification of an early one gives 17 degrees mechanical advance from my specification list but the later agrees with your 11 - 13. The last of the three is too new for my list so I don't know what timing that has.
However there is more to the curve than advance figures as the early one's test data is to run up to 3,200 rpm which the Minor engine will not reach. I'm sure Morris had a good reason at the time to install a distributor with that curve.

Alec

[kennatt]

did you check that the pipe was secure ie when you sucked on it did you get a vacuum,or did it just suck air,could be just split ends on the connectors