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airlifter
06-27-2013, 03:23 PM
When I built the engine on my TR6 I had the dist. rebuilt also. The car has been running fine until today when I noticed a misfire on acceleration. I drove the car about 100 miles and the miss became increasing worse. When I got home I checked the timing and the timing mark was moving around as before. Not as much, but still moving. I have about 1000 miles on the engine since the rebuild.

Any ideas or thoughts?

TR3driver
06-27-2013, 03:50 PM
Sounds like maybe someone forgot to lube the dizzy shaft and the dry bushing wore out quickly. Try grabbing the shaft and moving it from side to side. If you can feel it move, the bushing (and/or shaft) is worn.

You could also check the timing chain, and centrifugal advance mechanism, but my guess would be the bushing.

airlifter
06-27-2013, 04:35 PM
Sounds like maybe someone forgot to lube the dizzy shaft and the dry bushing wore out quickly. Try grabbing the shaft and moving it from side to side. If you can feel it move, the bushing (and/or shaft) is worn.

You could also check the timing chain, and centrifugal advance mechanism, but my guess would be the bushing.



I did oil the dizzy. Maybe not often enough. I put on a new timing chain and gears during rebuild.


I will check for play in the shaft. Thanks

Geo Hahn
06-27-2013, 07:59 PM
Some rebuilders do not replace the bushing -- not sure how they can call it rebuilt if they don't -- but I had one explain to me that he 'doesn't like to do that'. As a work-around some rebuilders use a Pertronix so a worn bushing is less of an issue.

Do you know if yours got a new bushing?

airlifter
06-28-2013, 07:25 AM
Some rebuilders do not replace the bushing -- not sure how they can call it rebuilt if they don't -- but I had one explain to me that he 'doesn't like to do that'. As a work-around some rebuilders use a Pertronix so a worn bushing is less of an issue.

Do you know if yours got a new bushing?
Not sure. I have a Pertonix that I removed earlier. I might try that until I get a new bushing.

thanks

airlifter
06-28-2013, 07:37 PM
The car sat all winter and did not lube the dizzy before I started driving thus summer. Senior moment.

dklawson
06-29-2013, 06:30 AM
What part of the dizzy are you talking about lubing when taking the car out of of winter storage? Are you talking about the cam that opens the points, the center hole where the pivoting cam action happens, the breaker plate, or the bushings? Can you oil the bushings on a fully assembled dizzy?

Geo Hahn
06-29-2013, 09:44 AM
Isn't the prescribed 'drop of oil' on that felt pad under the rotor supposed to find its way down to the bushing?

I also use a tiny bit of assembly lube on the cam as modern (red plastic) points seem to lose their gap more quickly if the cam is run dry.

TR3driver
06-29-2013, 12:21 PM
Isn't the prescribed 'drop of oil' on that felt pad under the rotor supposed to find its way down to the bushing?
I don't think so. It lubricates the joint between the shaft & the point cam, plus maybe the advance mechanism to some extent, but not likely to get all the way down to the bushing. IIRC there is even a nylon thrust surface in the body that would effectively act as an oil seal for the top of the bushing.

I believe the bushing is Oilite, and should be soaked in oil before installation (although newer ones may come already soaked).

airlifter
06-30-2013, 01:25 PM
When I installed the dizzy, i did lubricate the shaft etc. would't this take care of the bushing?

poolboy
06-30-2013, 02:00 PM
You mentioned swapping distributors earlier..have you ?

airlifter
06-30-2013, 05:55 PM
You mentioned swapping distributors earlier..have you ?

I changed the distributor whe I rebuilt the engine. The car has been running great until a couple of days ago.

poolboy
06-30-2013, 06:28 PM
What I meant was did you swap out distributors since the problem began ...because there seems to be speculation that the problem is with the current distributor ?
..............
Remember when you said this ?
"Not sure. I have a Pertonix that I removed earlier. I might try that until I get a new bushing."

airlifter
07-01-2013, 09:07 PM
I have not changed the distributor since the problem started. I don't have a spare.

poolboy
07-01-2013, 09:17 PM
Oh so you were talking about a removed Pertronix Ignitor..not a removed Pertronix distributor..

airlifter
07-02-2013, 04:57 AM
Oh so you were talking about a removed Pertronix Ignitor..not a removed Pertronix distributor..

That is correct. I guess I wasn't clear about that.

thanks

Geo Hahn
07-02-2013, 09:26 AM
When I built the engine on my TR6 I had the dist. rebuilt also...

My prior point was that some distributor rebuilders install Pertronix units instead of going to the trouble of replacing a worn bushing. If this was the case with your distributor then your return to points may be part of the problem you are experiencing.

Of course, this doesn't account for the fact that it seemed to run well until recently.