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QUESTION ??? 25-D distrbutor

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PAUL161

PAUL161

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I have two 25-D dizzies on the shelf. One has .004 side movement on the cam lobe and the other has 005.5 side movement. Checked with a dial micrometer. What is the maximum allowable side play on the shaft? I know ideally it's zero, but how far can they go without effecting the ignition. /ubbthreads/images/graemlins/crazyeyes.gif PJ <font color="purple"> </font>
 
Re: Question on the 25-D distrbutor

IMHO that is preaty small. Remember it is turning only one way and with that small a variance will preaty much stay stable.

However that said, lets see what the experts say.
 
Re: Question on the 25-D distrbutor

Thanks Jack. I think I'm going to rebuild the .004. The one on the 72 is questionable.PJ
 
Re: Question on the 25-D distrbutor

The problem I had with my 25-d4 was that the wear didn't seem consistent on each firing point. I could see a few variations while running the car with a timing light hooked up. It also had uneven wear on the cam where the points block rubs. It was an old unit that had been neglected, much like the rest of the car when I first got it.
 
Re: Question on the 25-D distrbutor

All or most of these little cars have been neglected at one time or another. The only way to correct this is one peice at a time, and clean, check and replace as required.

Yep I know and the other factor is as your budget will allow.

Don't forget all thse distributors have a small peice of cotton batting and a drop of oil in the top center of the cam. This is what lubes the bearing so don't forget that drop of oil every 3K when you do the other stuff.
 
Re: Question on the 25-D distrbutor

If every owner had done all the maintenance necessary to our LBC's, we wouldn't have anythin g to do but drive them! & I enjoy the tinkering as much as the driving!
 
Re: Question on the 25-D distrbutor

The little felt pad in the center of the cam lobes was used on a lot of cars for years, but did you ever take one apart and find any oil on any of them? Very rare. You know what they say; Out of site, out of mind. /ubbthreads/images/graemlins/rolleyes.gif PJ
 
Re: Question on the 25-D distrbutor

Mine, wave, hehe.
 
Re: Question on the 25-D distrbutor

And mine.Though my neighbour looked at me quite blankly when I put that drop of oil in there. /ubbthreads/images/graemlins/savewave.gif

Stuart. /ubbthreads/images/graemlins/cheers.gif
 
Re: Question on the 25-D distrbutor

Just goes to show ya who knows what.

Good on ya.
 
Re: Question on the 25-D distrbutor

So, you put the oil in the top of the cam where the screw is? Sounds like I didn't know it either.
 
Re: Question on the 25-D distrbutor

Thats the spot, is supose to be a small amount of cotton wicking on top of the screw to keep the oil in there. Just one drop will do. Any kind.
 
Re: Question on the 25-D distrbutor

[ QUOTE ]
Thats the spot, is supose to be a small amount of cotton wicking on top of the screw to keep the oil in there. Just one drop will do. Any kind.

[/ QUOTE ]

Learn something new everyday. It was missing in my 25-D4. I'll have to check and see if it's there in the new Pertronix dizzy.
 
Re: Question on the 25-D distrbutor

Care and feeding is most important.
 
Re: Question on the 25-D distrbutor

...Only if you want to "advance." /ubbthreads/images/graemlins/jester.gif
 
Re: Question on the 25-D distrbutor

Put the rebuilt,[new points,condenser,roter,wires], dizzy in last night. the one with .004 cam side movement. The engine idles better, smoother. The old dizzy has .011 play in the cam lobes. You could almost hear it rattle! The distributor was definitely the problem with it not idling the way it should. /ubbthreads/images/graemlins/thumbsup.gif /ubbthreads/images/graemlins/thumbsup.gif PJ
 
Re: Question on the 25-D distrbutor

[ QUOTE ]
Put the rebuilt,[new points,condenser,roter,wires], dizzy in last night. the one with .004 cam side movement. The engine idles better, smoother. The old dizzy has .011 play in the cam lobes. You could almost hear it rattle! The distributor was definitely the problem with it not idling the way it should. /ubbthreads/images/graemlins/thumbsup.gif /ubbthreads/images/graemlins/thumbsup.gif PJ

[/ QUOTE ]

After I got the weights free, mine rattled in a big way. I never measured the play at the end of the cam, but it was visible. Car ran fine this morning until some dirt went through the gas or something. Hopefully, that's taken care of now.
 
Re: Question on the 25-D distrbutor

The amount of vertical (end to end) play in the cam assembly is around .003-.005" on a new distributor, so in that range is good.
Horizontal or side play in the assembly should be imperceptible, not to be confused with shaft run-out which is actually a bend in the main shaft.

Did the 25D distributors ever come with a felt pad under the rotor? I can't say I've seen a 25D with one installed in the last 7 or 8 years.
Jeff
 
Re: Question on the 25-D distrbutor

Only thing I can say for sure is that the Bugeye MK I and the MK II did for sure.
 
Re: Question on the 25-D distrbutor

I would bet that most all of them did Jeff. I used to restore antique cars a few years back and most all the old distributors that I found had a felt pad in them. I never found one, that I can remember, with oil in it though. /ubbthreads/images/graemlins/rolleyes.gif PJ
 
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