Author Topic: Time to Get Into the Motor - Part 2 (Update)  (Read 15658 times)

chetbrz

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Re: Time to Get Into the Motor - Part 2 (Update)
« Reply #15 on: February 01, 2015, 03:15:29 PM »
Guys, I know and understand the concept of backlash and that things can't be so tight that they'll bind.  My main question with what I found, along with the photos and videos previously posted, is it showing too much play?  It seems too much to me, but I'm not 100% sure.

Ted

Ted,

No one is ever 100% sure.  If it seems like the assembly has to much play and you can do something to lessen it then do try it and see if it helps.  Troubleshooting a problem is the same as solving a mystery and this is done by eliminating suspects.  Your distributor assembly is just one suspect.   If the assembly is not capable of skipping a tooth and going out of time than you need to move on to your next logical suspect.  I think the problem you are having is you can't seem to definitively say whether the assembly is good or bad.  Without that determination you can't move forward in the troubleshooting process.  I don't believe anyone can remotely make that determination for you. 

Fix what appears to be a problem, after all even if it isn't causing a problem making something a little better is never a bad thing.  Eliminating a suspect is always good.

Chet...
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frankp

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Re: Time to Get Into the Motor - Part 2 (Update)
« Reply #16 on: February 01, 2015, 04:35:22 PM »
Ted,

Try a thin, flat blade screwdriver to pry off the cap.  Seems to me, if you have discovered a position where these gears "lock," it should be corrected.  Obviously, just opinion.

My reasoning why this is not a camshaft gear issue:  If the crankshaft and camshaft gears are not in their correct alignment, both valves for a given piston will not be closed when the piston reaches TDC.  I know these engines are very forgiving, but my opinion is, even if it were to start,  it would run rough and have no power.  Perhaps like running with spark advanced continuously.  Further, if after out of time, it may be corrected by re-positioning the distributor, then this assembly is suspect.  (The neck bone is connected to the thigh bone, but not directly.)  Shooting holes in my reasoning is entirely acceptable.

frank
frank p

racertb

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Re: Time to Get Into the Motor - Part 2 (Update)
« Reply #17 on: February 01, 2015, 06:08:00 PM »
Thanks guys, got the end cap off...very easy... should have tried before I asked :)

One thing I did this time to simulate the operation more realistically was to install the advance/retard bracket on the housing and then put the distributor in. Now, I'm not experiencing the lock up when I was turning the shaft drive while pushing it in.  The drive turns freely whether I'm pushing it in or pulling out on it.  The play is still there, however, just no lock up or binding.

I did observe the two gears turning together and there is a little play, but it's hard to say if that's the issue.   I made a video and will post tonight or tomorrow.

Frank, I agree with you and some others.  I really don't think it could be the cam gear if I can keep getting the car to start and keep it running if at least for a while.

Now, time to go watch the Superbowl...

Crazydave

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Re: Time to Get Into the Motor - Part 2 (Update)
« Reply #18 on: February 07, 2015, 10:40:52 PM »
I measured the mirrored spare believed to be from a 28. They are of the same design and operate the exact same way, tolerances should be the same. I pushed the mounting surface tight against my workbench, then pulled the shaft out and used a straight edge to mark. Then pushed it in, marked again, then measured. It came out to about 1/32nd of an inch. Very little movement. I also took pictures of how far the gear traveled in the housing, visually it reflected the measurement and collar movement. This base turns freely and does not have the weathered damage, I have seen on others. What does the inside of the housing look like? How far does the drive gear walk when you are pushing and pulling the shaft? I would take the shaft out and make sure the roll pin is holding it where it needs to be. See my attached pictures, hope it helps.

Pulled tight out

Pushed tight in. If you look close ypu can see the difference.

racertb

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Re: Time to Get Into the Motor - Part 2 (Update)
« Reply #19 on: February 08, 2015, 02:54:07 PM »
Dave:

I attached some photos and a couple videos earlier.  To answer your question, the back and forth play while moving the drive is about 1/16".  If I were to pull out on the drive to take up the slack and put a shim between the housing and retaining collar, the gear lines up perfectly like in your photos.  Without the shim, I can visualize the drive moving back and forth.   By taking up the slack with the shim, the gear will be perpendicular to the distributor gear.   The drive still turns freely.  The distributor also has some axial/vertical play of about 1/16" as well.  I'm thinking of not touching the distributor at this point.

On a side note, it was mentioned earlier on that it looks like my housing was once repaired or modified.  The housing itself is good, but I just noticed that someone added a brass or bronze sleeve where the drive itself rotates.  A zerk fitting for grease was also added to the housing right where the drive is. I think some added grease will also take up some slack.

Ted

O

chetbrz

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Re: Time to Get Into the Motor - Part 2 (Update)
« Reply #20 on: February 08, 2015, 07:07:10 PM »

On a side note, it was mentioned earlier on that it looks like my housing was once repaired or modified.  The housing itself is good, but I just noticed that someone added a brass or bronze sleeve where the drive itself rotates.  A zerk fitting for grease was also added to the housing right where the drive is. I think some added grease will also take up some slack.

Ted,

It sounds to me that the brass sleeve was installed to fix an oblonged drive shaft hole.  Brass was probably used so as not to cause anymore wear to the steal drive shaft. The brass sleeve has probably gone the way of the original drive hole.   May be time to check the concentricity of the hole the drive shaft turns in.   Is the shaft removable without damaging the assembly ?

Chet...
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racertb

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Re: Time to Get Into the Motor - Part 2 (Update)
« Reply #21 on: February 08, 2015, 07:41:36 PM »
Chet,

I've had the shaft out with no problem and it looks fine to the naked eye.  The sleeve looks good too.  It all fits together nicely and turns freely without any other movement other than the play I mentioned before.  I shot some grease in the zerk fitting and the drive turns silky smooth.  I put a "machine bearing" on it - just a thin washer that fits around the drive between the retaining collar and housing - that takes up 95% of the slack.  I'm guessing with that and the grease that I've got it dialed in enough to give it a go.  Again, going to hold off on the slight play of the distributor for now.

I might wait to see what Dave's findings are first with his aluminum drive; also thinking about calling Tom at Antique Auto Parts Cellar and ask him about tolerances since he apparently makes a brass replacement housing with the drive. 

I can only hope that I am on the right track... either way, this is definitely a learning experience :)

Ted

29plycoop

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Re: Time to Get Into the Motor - Part 2 (Update)
« Reply #22 on: February 10, 2015, 01:11:54 AM »
Keep in mind the two gears should run together at the center of both gears. Any shims added should be to keep this alignment. If there is truly 1/16 end play that should be reduced to about .010 with very little side play between the gears. The side play of both gears can be checked by turning the rotor back and forth with light pressure. A small amount is OK. Any large amount will have to be adjusted. Hope this helps. - Rich
« Last Edit: February 10, 2015, 03:47:07 PM by 29plycoop »
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Crazydave

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Re: Time to Get Into the Motor - Part 2 (Update)
« Reply #23 on: February 12, 2015, 12:12:31 PM »

I might wait to see what Dave's findings are first with his aluminum drive; also thinking about calling Tom at Antique Auto Parts Cellar and ask him about tolerances since he apparently makes a brass replacement housing with the drive. 

I can only hope that I am on the right track... either way, this is definitely a learning experience :)

Ted

Ted,

The aluminum housing was built by referencing the 28 housing I posted pictures of and Franks 29 spare. It will be as tight, or tighter as the pictures I posted above. It how ever is not perfect, and needs a few tweaks to make it right.  I have not any issues, but run time has been limited. I will plan on taking it apart soon and checking for wear inside. 

racertb

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Re: Time to Get Into the Motor - Part 2 (Update)
« Reply #24 on: February 12, 2015, 07:38:49 PM »
Thanks Dave, just let me know when you can.   I appreciate your help.

Ted

Crazydave

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Re: Time to Get Into the Motor - Part 2 (Update)
« Reply #25 on: February 20, 2015, 01:35:21 PM »
When I first started hunting for parts and information I booked marked a page with information about someone who makes reproductions. (Antique Auto Parts Cellar)

I have now noticed it was Rich (29plycoop) who posted the info on smokstak (Time stamp April 2009)

Rich have you bought one of their reproductions? And if so do you have any pictures of it?

29plycoop

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Re: Time to Get Into the Motor - Part 2 (Update)
« Reply #26 on: February 22, 2015, 06:03:30 PM »
I purchased a set of gears for my distributor drive from Antique Auto Parts.  I reproduced the distributor housing out of aluminum and it worked very well. Just a note, the gears they sell must be installed as a set as they are not the exact same grind as the originals, but work very well. They do sell the complete housing and gears and have heard they also work very well. That is why they sell the housing and gears as an assembly so they have the right backlash. Good luck - Rich
« Last Edit: February 22, 2015, 06:21:08 PM by 29plycoop »
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Crazydave

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Re: Time to Get Into the Motor - Part 2 (Update)
« Reply #27 on: February 25, 2015, 08:36:18 PM »
Ted,

I have little vertical play in my distributor, maybe 1/32nd. In the attached pictures I tired to snap the gap.

All the way down


All the way up


My Housing



Crazydave

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Re: Time to Get Into the Motor - Part 2 (Update)
« Reply #28 on: February 25, 2015, 08:41:28 PM »
Here I have some pictures of the cam drive, and shaft driven by it. Notice the offset on both.





racertb

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Re: Time to Get Into the Motor - Part 2 (Update)
« Reply #29 on: February 25, 2015, 09:12:48 PM »
Thank you Dave!  This will be a great guide