Distributor movement

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bloodysalmon
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Location: Kirkby-in-Ashfield, Notts, UK

Distributor movement

Post by bloodysalmon » Fri Jul 12, 2019 11:29 pm

My Distributor shows a slight movement, probably only ->2% max in the rotation. Its fixed in the shaft so no up or down movement just rotational - is this something we would expect? If not where is the movement coming from ... any ideas?
Doesnt appear to be affecting the distributor working as the tension is taken up in the shaft rotation too.
Chris Blood
TC1472,TC2686,TC4245,D-type D0407

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Steve Simmons
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Re: Distributor movement

Post by Steve Simmons » Fri Jul 12, 2019 11:33 pm

Are we talking about the body, the micrometer or the cam? The body should be rock solid on the shaft. The micrometers are notorious for developing play in the joints, which can be cured (for a while) by brazing or soldering. The cam does rotate against the springs, which is what gives the timing advance. With some force you can twist the cam quite a bit. But it shouldn't have "play". If it does, I would open it to see where the play is. There are several pivot points that suffer wear over time. I guess the main thing is that the timing remains stable.
1949 TC8975 / XPAG 9609
http://www.mgnuts.com

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bloodysalmon
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Location: Kirkby-in-Ashfield, Notts, UK

Re: Distributor movement

Post by bloodysalmon » Sat Jul 13, 2019 12:40 am

i believe its not the micrometer nor the cam, its the body. The locating pin underneath the distributor has a shoulder to ensure no/little rotational movement but there is some. Should there be a washer with this location pin so it traps the shaft in place perhaps?
Chris Blood
TC1472,TC2686,TC4245,D-type D0407

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Steve Simmons
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Re: Distributor movement

Post by Steve Simmons » Sat Jul 13, 2019 8:20 am

I had that happen on a couple distributors in the past. You definitely don't want the body moving because it can greatly affect timing each time it moves! Once I had to wire mine in place while on an extended tour, until I got the car home where I could deal with it.

Since it needed a rebuild anyway, I had it repaired while it was there. I don't recall exactly what he did but I believe he pinned it in place. I never had a problem again. The guy is here in California so probably not much good to you, but Distributor Doctor over there in the UK is really good. I'm sure he could fix it up.
1949 TC8975 / XPAG 9609
http://www.mgnuts.com

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bloodysalmon
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Re: Distributor movement

Post by bloodysalmon » Sat Jul 13, 2019 9:36 am

yes, good advice Steve, wire it will be for now ... I just want to get this 'oily-rag' TC on the road, so perhaps another refurbishment job to be done another day
Chris Blood
TC1472,TC2686,TC4245,D-type D0407

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