225 Delco Distributor Gear Failure...

I recently had a dizzy gear failure while warming up several weeks ago. Didn’t think much of it as it was a used delco that I used for a pertronics conversion from the prestolite that was in it. Pulled the dizzy and put a new gear on the shaft and freshend up the dizzy while it was out. While I had it down I also updated the oil pump with the taller gears and spacer and changed the relief valve spring to bring the pressures up a bit at hot idle when I installed the delco dizzy the first time. I did have the wrong spring in it as it had 100+ psi at cold idle. All went back together with proper clearances, oil pump and dizzy.
Now, less than 30min of run time each time I have ate another gear up.

My question is, with the higher pressure the pump is working to produce now, could this have caused premature wear on the dizzy gear with the extra force ? The spring I have in it is way too high and I will pull and replace to get the pressures down lower with the next gear swap.

 

Yes. Even ta performance does not recommend hv pumps. Did you follow correct procedure for shimming the gears / cover ? It may be binding / setup too tight.
I carry 20 lbs hot idle on a stock pump with a good cover.

 

Yes, it was shimmed and set up properly and pinned in place with the exception of the pressure relief springs, I had a job change and moved across the country so it was left like it was to just move it on and off the trailer. It would only hold 4psi at hot idle before hand and peak at 20psi.
I have an old dizzy shaft without the gear and the pump shaft turns fairly easy with minimal resistance.

 

Unless the block has had the passages reamed a HV pump won't do much for you. The #1 cam bearing is notorious for wearing out ( TA sells a modified one) Does your distributor have play up/down ?

 

I broke a dizzy gear in a 2.3L ranger by running 20W-50 oil on a cold day..

 

First, there is a difference between a high volume pump and a high pressure pump.
A HV pump pushes more volume at a specific pressure. High pressure pumps push the same volume of oil at higher pressure. What this means is a HV pump set at 40PSI will move more oil at that pressure that a stock or HP pump.
HV pumps set at stock PSI will exert the same pressure on the drive gear as a stock pump because the bypass will open at the same pressure. What it will do is move more oil at lower RPM's, maintaining pressure better.
So, you have a stock pump pushing 20PSI at idle, running up to 40PSI@1500RPM. Installing a HV pump set at 40PSI will (can) give you 40PSI at idle as well as 1500RPM because it is moving more oil (volume) at lower RPM's. The bypass will still open at 40PSI giving you "stock" oil pressure through out your RPM range.
Many HV pumps, such as the Melling HV pump comes with a selection of bypass springs that can increase pressure as well as volume. These springs can increase the pressure on the drive gears because you are increasing the oil pressure as well as the volume.
I've been running a Melling HV pump for 30 years with no issues. I love it because my style of wheeling involves idling over obstacles, many times with the RPM's dropping below 400. The HV pump helps keep the pressure up during these ultra low RPM sections, insuring the bearings don't starve under load.

 

Fair points but low psi points to a worn cover or loose tolerances. No pump will make up for that. As the sending port is in the first passage between pump and cam bearing, has no real reference on what's going on in the rest of the engine.

 

Can you get a look down at the driving teeth down the distributor hole? How do they look? If my oil pressure was that low, I would pull the pan and look at the rods and mains. I suspect there is too much clearance, as well as the front cam bearing most likely being worn out. I have been lucky with covers but others have had covers that were worn out. May be time for a rebuild. After the rebuild, I would run stock gears with the clearances being tightened up.

 

My post wasn't to dispute low pressure can be caused by excessive clearances. It was to point out that a pump moving larger volumes of oil with a pressure regulated at 40PSI won't create any more stress on the drive than a stock pump set at the same pressure.
It was also to point out a couple of reasons for the upgrade. Engines that see abnormally low RPM's can benefit from added volume, which equates to higher oil pressures in those situations, and the engine needs no additional modifications to reap the benefits.

As to answer the OP:
Yes, if you are running 100PSI you run the risk of gear or roll pin failure.
The fact you have lost two gears, one on the stock pump and one with the HV pump makes me question the drive gear more than the pump.

 

With the dizzy pulled the drive gear on the cam is toast as well. So apart it all comes. Anyone have a part # for the cam side drive gear? I can pick up the dizzy gear at most Box stores but not finding much on the internal gear...
looks like I’ll be calling TAperfomance for it if I can’t find anything elsewhere...

 

Bumping the motor over to TDC before pulling the dizzy I had no play and then lots of play pointing to the gears, once pulled, both the cam gear and dizzy gear were toast

 

That is unusual to loose the gear on the cam. This also points to a severely worn #1 cam bearing. This area relys on spray / splash oiling. Deeper inspection of overall engine health is in order.