15 replies to this topic

[Steve-O 2014]

Replaced the points and set the gap with feeler gauges but checked the dwell and it was no where near the angle the haynes manual says anyone know why?

 

Im using a Clarke Meter with the red probe on the neg terminal of the coil and the black lead on a earth point.

 

Adjusting the gap to 0.010 gets it to a dwell of 49 Deg but the manual states a gap of 0.014 - 0.016

 

What should I go with? Dwell or Feeler Gauge settings? 

 

Thanks

[Dr s]

Dwell, that's a measure of how much of the time the points are opened and closed.

Setting the gap is just a crude way of trying to set this.

[KernowCooper]

Dwell is the time the points are closed, I suspect you have a small amount of wear in your shaft bushing in the distributor, if you set the dwell then if the points heal wears in the points gap will close up from your 10thou and you may have trouble starting. If you have a bit of play then now is the ideal time to convert to electronic ignition, which wont be effected by a small amount of play in the bushing. Less than £30 and 2 problems sorted.

[Steve-O 2014]

Going to get the britpart kit ordered and keep the points as spares, Does dwell need set at all on these kits?

 

I thought going below 0.010 to get the dwell perfect was getting to be a small gap

 

Oh the haynes manual mentioned sliding contacts being 57 deg dwell and non sliding contacts 54 deg does the 45d use sliding contacts? 

 

At least I learned how to set points today, never done that before

[KernowCooper]

No dwell to set on electronic Steve, just fit mate full install guide in the FAQs Electrical if that helps

[Ethel]

Sliding contacts were on the 59 (A+ engines), it's the little white plastic fork bit that fits round the pin on the baseplate.

[carbon]

Steve,

 

If you need to get the car back on the road for tomorrow morning I would go with setting the points gap with feeler gauges.

 

Also if you have not altered the distributor position then the 15 thou gap should keep the ignition timing close to what had before. If you close up the points gap from 15 thou to 10 thou this will have the effect of retarding the ignition timing slightly, all other things being equal.

[Steve-O 2014]

Thanks its ok, i dont need it on the road as insurance ran out today, i just wanted to get it running again before removing the engine to replace seals etc. Also going to rewire a few things i think while engine is out

[Rog46]

When points wear you usually get a pimple on one with a matching pit on the other. If you then try to set using a feeler gauge you get a gap bigger than measured.

You can only set points accurately using feeler gauge if they are new. At any other time the Dwell meter is much more accurate. I always use a dwell meter!

[KernowCooper]

Only thing is setting the dwell angle is to ensure that you dont have a lot of play in the distributor shaft bushing, otherwise the result could be difficult starting or failure to start, something worth checking when lubricating the shaft mechanism

Edited by KernowCooper, 25 January 2015 - 10:51 PM.

[dklawson]

With Lucas distributors you are always setting the points with feeler gauges, you are only "checking" the dwell after the adjustment.  The material transfer Rog46 mentioned requires you to "dress" used points before setting their gap.  They used to sell points files just for that purpose.  You would remove the points, file the tips flat, then set the gap.

 

By comparison, during the 1960s and 1970s General Motors cars with Delco distributors had a "window" on the side of the distributor cap.  You would connect your dwell meter, start the engine, slide the window "up" on the dizzy cap and use a hex key through the window to change the points gap (and therefore the dwell) with the engine running.  It was GREAT.  I wish there had been a way to incorporate that easily onto Lucas distributors.

[KernowCooper]

Lucas did a distributor which was fitted to some Rover V8s which had a allen key dwell adjustment in the side, important to get it right on a V8

[dklawson]

If the Rover V8 is the one I think you are talking about (introduced in the mid-1960s), that was a Buick/GM design so it would have had the Delco distributor I mentioned above.

[KernowCooper]

Had me thinking then Doug, dug my Lucas books out and sure enough Lucas did make one here in the UK for the Rover P5/P6 MGB V8 and others before it went electronic, the Distributor Doctor has some old stock new ones here for sale http://www.distribut...stributors.html

 

with external dwell

 

I suspect its the same with the V8s like the Mini which used a Lucas and for a period used the Ducellier, and they had a backup the Delco

Edited by KernowCooper, 26 January 2015 - 09:40 PM.

[dklawson]

Unrelated but similarly... there was a period during the early 1970s when the TR6 production line was dealing with a shortage of Lucas alternators.  Those cars were outfitted with Delco alternators which can confuse mechanics who are not used to seeing anything but Lucas installed.

 

Regardless, while that Lucas distributor with dynamic dwell adjustment may look cool (trim and sleek compared to Delco)... I wonder how easy it is to find replacement points and condensers for it as opposed to the Delco unit?