Eagle Eye - Meep's new name!

[cr8crshr]

You're in cow town right? not too far from me.

Yep sure am JB. I will get pics up later for those interested. MeepMeep...That bushing should not be loose in the block. That is the purpose of the burnishing tool. It seats the bushing against the block hole it resides in causing it not to spin or turn. The distributor shaft spins inside the bushing while the bushing remains tightly against its hole. I bet dollars to doughnuts that that is the cause of JB's first failures and the wearing down of the bronze tooth gear. I hope I am wrong but in my experience that process is always over looked and results in similar failings such as JB's. I could be wrong too but when it comes to re-building engines especially MOPARS, I follow the FSM and the MOPAR specific build books to the letter. I have never had a failure such as this by doing the burnishing step...cr8crshr/Tuck

 

[bigmanjbmopar]

I don't think that's what he meant, I was standing by him when he installed it and his homemade install tool worked perfectly. and there was no way it could have been loose. I think he is saying after rechecking the new gear in the new bushing all is well I felt it myself and it was nice and snug no slop at all unlike before the old one you could feel the side to side movement on the gear shaft inside the bushing.

I will say this, I installed the first bushing myself in the bare block I think it was the first thing I did after getting it back from the machine shop and I did not burnish it. just carefully tapped it in evenly and it was snug. The looseness we are talking about is on the inside of the old bushing as if the shaft was warped and wobbling around the bushing elongated.

But hey I am for sure an ameture builder so I could be completely wrong and on the verge of blowing my motor lol well that's not really funny but this is why I asked for some tuning help from experienced eagle eyes! I think Meeps true name should be the Professor, sharp as a scientist and experienced. Unless all those old parts hanging off his shop walls are failed build attempts? WHAT!? LMAO J/K

 

[cr8crshr]

I don't think that's what he meant, I was standing by him when he installed it and his homemade install tool worked perfectly. and there was no way it could have been loose. I think he is saying after rechecking the new gear in the new bushing all is well I felt it myself and it was nice and snug no slop at all unlike before the old one you could feel the side to side movement on the gear shaft inside the bushing.

I will say this, I installed the first bushing myself in the bare block I think it was the first thing I did after getting it back from the machine shop and I did not burnish it. just carefully tapped it in evenly and it was snug. The looseness we are talking about is on the inside of the old bushing as if the shaft was warped and wobbling around the bushing elongated.

But hey I am for sure an ameture builder so I could be completely wrong and on the verge of blowing my motor lol well that's not really funny but this is why I asked for some tuning help from experienced eagle eyes! I think Meeps true name should be the Professor, sharp as a scientist and experienced. Unless all those old parts hanging off his shop walls are failed build attempts? WHAT!? LMAO J/K

OK JB got it. Glad it was snug and not able to move. As stated, the burnishing actually expands the bushing hole that the oil pump shaft slips into and the gear then rides on top of it. And, until you get the distributor back in there will be an ever so slight side to side play between the bushing and the shaft. After re-looking at the before pics of that bronze gear on the underside it appeared to me that the bushing was some how causing that galling on the bottom surface. And the only way for that to happen was for the bushing to be loose. Or the gear teeth failing caused its pieces to rub down the underside as they wore off. But glad you are satisfied with Meep Meep's fix...cr8crshr/Tuck

 

[Meep-Meep]

Bigman has it correct in post 22. The bushing fit tight in the block and the old bushing required a slide hammer to remove. The failure of the original bushing is due to a flawed oil pump drive. The hole in the top of the bronze gear that the distributor shaft fits into (slot) was too tight. .485" vs. .515" on my replacement shaft. The distributor shaft is pretty much 1/2" dead on. That interference fit between the distributor shaft and the old gear is what prevented the distributor housing to sit flat against the block. And when the hold down was tightened it just jammed the dist. shaft hard against the gear, which jammed the gear against the thrust surface of the bushing. The wearing out of the bushing hole is likely due to the distributor shaft not being perfectly centered when jammed and running in an elliptical orbit. It is imperative that the distributor shaft only have contact to the oil pump drive through that slot and have just a little play at that. No other influence other than rotational is allowed.

In addition, the oil pump drive gear runs against the thrust face of that bushing but there is no real load except what happens due to the direction of rotation of the 90 deg gear arrangement. Also think about how that gear arrangement works. The action produces a lot of scuffing of the teeth, so when the resistance to rotation is too high the teeth will wear quickly.

 

[cr8crshr]

Bigman has it correct in post 22. The bushing fit tight in the block and the old bushing required a slide hammer to remove. The failure of the original bushing is due to a flawed oil pump drive. The hole in the top of the bronze gear that the distributor shaft fits into (slot) was too tight. .485" vs. .515" on my replacement shaft. The distributor shaft is pretty much 1/2" dead on. That interference fit between the distributor shaft and the old gear is what prevented the distributor housing to sit flat against the block. And when the hold down was tightened it just jammed the dist. shaft hard against the gear, which jammed the gear against the thrust surface of the bushing. The wearing out of the bushing hole is likely due to the distributor shaft not being perfectly centered when jammed and running in an elliptical orbit. It is imperative that the distributor shaft only have contact to the oil pump drive through that slot and have just a little play at that. No other influence other than rotational is allowed.

In addition, the oil pump drive gear runs against the thrust face of that bushing but there is no real load except what happens due to the direction of rotation of the 90 deg gear arrangement. Also think about how that gear arrangement works. The action produces a lot of scuffing of the teeth, so when the resistance to rotation is too high the teeth will wear quickly.

Thanks Meep Meep for the further clarification. I have attached pics of the Miller Tools I have and are used for the bushing. The first pics are the removal tool, and the second is the burnishing tool. These really make the job a whole lot easier when removing and installing the bushing. Notice the cutting threads on the removal tool as they bite into the busing and then when you tighten the nut down on the collar disc it pulls the old one out real nicely. No more hammering on a rod from the bottom to get it out. I suppose a slid hammer will do just as well too. Notice especially the install tool as some times the hole of the bushing where the shaft slips through is really tight. With this tool it will open it up so the shaft slides in really nice and tight. Hope this helps...cr8crshr/Tuck:headbang:

 

[Meep-Meep]

Thanks for posting pics of the factory tools. It's interesting that the removal tool I made is strikingly similar in function. Only difference is I cut the thread with a 1/4" pipe tap then use an adapter on the end of my slide hammer to pull the bushing. The Miller tool is much more elegant than what I cobbled up in an hour or so using parts from an old high vacuum valve and an 833 4 spd tranny. My installation tool is an old distributor drive with the gear teeth cut off in a lathe that I really made into an oil pump primer.

 

[bigmanjbmopar]

Yeah what he said! lol Nice write up very informative pinned for future generations of builders

 

[cr8crshr]

Thanks for posting pics of the factory tools. It's interesting that the removal tool I made is strikingly similar in function. Only difference is I cut the thread with a 1/4" pipe tap then use an adapter on the end of my slide hammer to pull the bushing. The Miller tool is much more elegant than what I cobbled up in an hour or so using parts from an old high vacuum valve and an 833 4 spd tranny. My installation tool is an old distributor drive with the gear teeth cut off in a lathe that I really made into an oil pump primer.

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My engineering skills are limited when it comes to making my tools Meep Meep. That being said, with innovations such as yours that is how these Specialty Tools come about. Nice work there. Hopefully this thread can be 'archived" somehow as it has been a most informative one. Others here will most likely need this type of info at some point...Thanks a Bunch...cr8crshr/Tuck