Oil pump failure

[cobra132]

On the last lap of sundays race I noted a small puff of blue smoke from my valve cover vents. Oil pressure was zero and I shut down. The oil pump gears shattered into about 25 pieces.(see attachment) The only engine damage appears to be 2 cam bearings that got fried. These will get repaired. I am going to replace the pump as the housing was also broken and change to billet gears. I am told the down side of using billet gears is that they ride on the crank and will wear it over time, but at least that should be a gradual process. Any comments? FMR :(

[Todd Covini]

Hey Frank!
Welcome to the website and thanks for the update on your car!
I think Matt White is going to be your Mod-Motor advisor on this one since he's been thru his motor before and is a fellow VT guy.

Get that AI car ready for duty because you're leading the AI points heading into Round 2!!! Last year a mod-motored rookie made a great run for the Championship and now you're off doing the same.

Let us know if you need anything during the rebuild!

-=- Todd Covini

[marshall_mosty]

Frank,
Looks like you need forged gears in the pump to go with the other forged internal parts.

I'm glad the bits and pieces didn't do more damage.

[oz98cobra]

Hi Frank,

I'm guessing that is the stock pump right?

We are at the point right now of deciding which way to go regarding the oil pump for our DOHC AI motor - rebuild the stock pump with billet gears - or replace it with the FRPP pump? The Ford Racing pump is what is used on the Cammer 5.0 in the Grand Am cars, and I haven't heard of any failures there?

[cobra132]

I think the FRP pump is the same as the cobra pump (HO). I don't know if it uses billet gears or not. These failures are unusual but there are numerous reports on the various mustang forums. I am going to replace mine with a HO pump with billet gears. FMR 8)

[oz98cobra]

That's the best bet as the FRPP pump does not have forged gears.

Looks like SHM and VT are currently out of stock - let me know if you find a source for these

[cobra132]

Scott at VT told me he has 75 gear sets ordered. Check back with him in 2 or 3 weeks @ 519-245-1164. FMR

[AI#97]

I know Daron and Frank have solved their search for the pump gear but here is the skivvy on why they are failing and I wanted it to be here for future generations who might be doing a search.

The Mod motor from ford moves a ton of oil and typically will see oil pressures ranging from 85-120lbs at idle when cold and will see a static oil pressure of 45-60 when the oil reaches 230 degrees. They need this oil pressure to feed the lash adjusters and the two/four sets of cam bearings. Ford did a VERY good job in designing the oiling scheme on these motors....however, they failed to inform their owners that the oil level should be checked every 500 miles or even less on the Cobra Motors. They generate a lot of vacuum and pass oil at light speed.

The history of these failures is actually VERY long and has been narrowed to cavatation of the pump due to lack of oil in the pan to be pumped. Billet and Cryo'd gears aren't totally necessary if you keep the pickup bathed in oil. Typically what has been the case is that these motors consume copious amounts of oil and begin to run low. Lazy owners who started this trend were letting their levels get down to 3 quarts and voila, you end up with a failure.

The nature of the failure is cavatation where the pump temporarily runs "dry" and then "hammers" and is shocked with a fresh load of oil at a high pressure after the pan is replenished. Cast gears are the most vulnerable but I had a stock pump setup in my car for 22k miles of DE and AX duty most of which had the great Canton pan which actually holds 7.5 quarts. Tack on the two large filters and some length of hose, and running the car a little high on oil keeps about 9 quarts total for the engine.

Basically, it's not what the gears are made of which is important, but rather keeping the oil flow constant. If you can, the best solution is the FRPP High volume pump with a set of billet gears along with the Canton pan and windage tray which are a must.

Tech update has been updated!!!

THX