Learn Me Shimming Distributors, Gear Wear Patterns, etc.

I have a Ford Lima 2.3 Turbo which eats distributor gears.  Stock, fancy bronze, etc. doesn't seem to matter, eventually things loosen up in there to the point that it develops a bit of a miss, and if you keep running it it will strip the distributor drive gear in general.  It has a stock oil pump, and on this engine the distributor is not driven by the camshaft, although the arrangement looks similar.

I am hoping that this is something I can correct by shimming the distributor- but I don't know anything about how to do that properly, or determine whether it is required.  Am I just looking for a little play?  Radial play?  Axial play?  Rotational?  Should I just follow a guide for ring and pinion wear patterns?  Should I just keep feeding it another $60 gear before every event?

Any answers appreciated, including just links to good articles about how to correct this.  

EDIS 4...

In reply to RossD :

This thing also drives the oil pump, so even a standalone wouldn't fix it. 

Had the same problem when I started dirt track racing a 2.3 with high volume oil pump. Went to the Ford performance catalog for their gear. Never had a problem after that (7 years)

Did you pre-soak the bronze gear in oil before installation? 

In reply to outasite :

No- is it supposed to be soaked?  I gave it a good coating of grease when installing, and it was fine for the last couple months.

In reply to ¯\_(ツ)_/¯ :

Yes, just like bronze pilot bushings. They a porous and absorb the oil. which will lubricate the gear in use.

Axial play should only be enough for oil clearance when all parts are fully warmed up. Looking at it cold (as you must) I would target .004- .006 inch. Radial clearance as provided by the distributor no more than .003 cold, it will grow with temp. I am unsure which way the axial will change with heat. Is it possible that the oil pump is miss aligned in a way that it is negating the axial clearance that you can measure at the bottom of the distributor? Or is the bottom of the distributor not perpendicular to the axis? Thus loading the gear after installation. Stock oil pump should not overload the gear. Also less than perfect fore-aft location of the gear on the crankshaft could be causative. Back in my F2000 days we never saw this failure. All the parts were 25 years newer then.... 

Looking at it, I think the main issue may be that I need a spacer- it seems like the gear is being pushed in to the point of binding when the distributor clamp is tightened.  Going to attempt shimming.

This issue has been consistent across several oil pumps, drive gears, distributor gears, and distributors.  The distributor that was in there has crazy radial play now, so I'm going to swap my spare and see if that temporarily fixes it.

Are you missing a washer/shim between the gear and the housing?

I have 4 distributors here and none have a washer or shim there.

Swapping to my spare distributor fixed the problem completely, so it was either a worn gear (unlikely, looks pretty good still) or the radial play (.050"+, most likely our culprit) berkeleying things up.  I'm going to order shims to see if I can correct the problem.

Shimming won't do anything for gear wear. How much oil pressure has the engine? 

In reply to ChasH :

My current theory is that bad alignment is leading to radial play in the distributor shaft, which then leads to gear wear.  Bad theory?

Engine makes 40-60psi oil pressure until it gets good and hot and the oil cooler thermostat opens, at which point it's more like 20-40psi.

A worn bushing in the distributor body could cause misalignment. Shimming won't correct that or any other radial play. Axial location of askew gear isn't critical, which is one reason this type of gear is used here and why shimming isn't going to change anything.  How does the other gear look? 

Does it have a stock aux shaft or is it an aftermarket billet shaft ala Esslinger?  Billet has to use a bronze gear, and it is a wear item and it's probably best to use theirs.  Is the aux shaft thrust correct?  If the aux shaft thrust isn't properly set and/or the aux shaft is moving fore and aft, the distributor gear is going to take a beating.  A properly mated OEM aux shaft and gear should last indefinitely as long they are lubricated properly with an oil that has good high pressure lubrication characteristics.  You might try finding a good mated set, aux shaft and distributor, from a donor engine and install both.  Don't take the gear off the donor distributor and put it on your old one, use the donor distributor.  Junkyards are full of 2.3 Ford fours.  Look for Rangers.

It's a billet Esslinger aux shaft, and a bronze gear.  Before that, I used a known good (many miles, driven by me) OEM shaft and gear from a different engine-this engine chewed them up in a few hundred miles.

What I'm suggesting is that the alignment this engine puts everything in might kill distributor bushings quickly, which then results in play, which then causes gear issues.  Thoughts?

I think I would check with Esslinger and see if they have information on what to check to make sure everything is aligned properly.  It is their shaft and gear, and they have been doing these engines for a long time.  Maybe send them a couple of failed gears for analysis?

It seems you have a bad block or a bad jackshaft. If I had to guess which was bad, I think I'd choose the jack shaft. In any case. you'll likely get a better response from Esslinger than Ford.