new case, distributor drive issues

[rodjr]

So i have a new as41 case for a build, and i am going over some early test fitting. I have a dvda, converted to svda distributor that was rebuilt by tasb as well as a known good dvda, and 2 different drive gears. No matter what combination i use it is very difficult to engage the distributor into gear and once i do it is pretty difficult (you need a good whole hand grip on the rotor) to turn the dizzy shaft through about 90 deg of the rotation. Both turn smoothly until they engage each other.

If i pull the gear up and try to bring the distibutor and gear down into the case together, the distibutor will wedge in the hole and you can clearly see it is not perpendicular to the mating surface on the case. I am concerned i may not have a straight hole in the case? Any thoughts?

[kreemoweet]

Seems unlikely someone made a curved hole in the case. Are those drive pinions aftermarket?
The drive dogs should move freely perpendicular to the pinion slot direction (on their securing pins). There should be some small clearance between dogs and slot.
Sounds like slot offset on pinions is incorrect, or you are dealing with burred/damaged parts.
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[rodjr]

Both drive gears and both dizzy's are oem vw, both work fine when installed in a used german as41 case.

[krs.br79]

[HRVW]

I had a similar situation at one time so I just used a honer fitted with some FINE emory sand paper...used a drill for a couple of secs...cleaned and tested the drive gear until it turned smoothly when oiled. Installed a dist for a final test

EDIT: A froze dist drive gear will EAT the BRASS gear as the picture shows. Steel is stronger then Brass.

[rodjr]

I will definitely get it fixed 100% before assembling, hoping things will clearance themselves, is not my style.
I did discover the pin in one of the drive gears is not driven in far enough and displaces the retaining ring on one side when the gear is forced over. I will address this in the morning and see if it helps, at least with that dizzy.

[kreemoweet]

It's not unusual for the dist. bore on a new case to need a little work to make the drive gear slide in and rotate freely, as the fit is quite snug. However, the OP says each
pinion installs and spins freely in the case, it is only when the distributor is inserted that things bind up. The distributor has no moving contact with the bore.
Therefore, one would suppose the problem is with the mesh of the dist. drive dogs and pinion gear. I would be checking for dist. shaft runout, or a drive dog that has
been distorted from the sometimes very large forces needed to remove the drive dog pin.
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'68 bug: seized by the authorities
'71 kombi: not yet seized by the authorities

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[esde]

Is it difficult to turn through the full 360 degrees of rotation? Given the slotted drive I would think the binding would be relieved every 180. Maybe find a straight edge that will fit down the bore to see if it is straight, though it's hard to imagine it isn't. But maybe? I would suspect the bore for the end of the drive, where the washers sit, could be off center from the distributor bore. But you say the problem is visible as you insert the distributor..
Quite a puzzle, but apparently it is the case.
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[mark tucker]

make sure the dist drive(the part pined to the dist shaft) is free and floating, if it's still or riged it will not center and cause tight spots. some aftermarket dist have this issue as do some old rusted,funkey,gynkey,wonkey&just plain stuck ones will do. but what i read hear is it seems the case was machined wonkey.....if so....send it back. it could just be the top cut or it could be the hole....top isant realy an issue but the hole out of aline can realy effthings up.

[MURZI]

My thoughts..... If I just spent 800 bucks on a case some one would be making it right. Only labor I would be doing is boxing it up to ship back. Any mods you do will be on you.
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[rodjr]

Well, success. I have been on this for the last 5 hours but spins very nice now. Really it was a combination of factors. The pins in both my dizzy drive dogs were not centered well so the pins would force the retaining ring out when the dog shifted to one side. I am sure this is why they did not like to come down through the upper hole together. Burs on the case and the top of at least one of the drive gears. I took the case to a buddy of mine that's a machinist and he made a bushing for the dizzy hole and ran a reamer into the lower hole for the drive gear. Seamed to only remove a tiny touch of super fine shaving from entry of the hole, at the base of the chamfer,but that did it, dizzy spins as good installed as it does loose in my hand. Thanks for all the help!