3.4 Distributor gear failure

[Kreb]

At the end of a track day, at about 5500 RPM in 4th, my engine died. Ultimately I found that several teeth were missing off of the distributor gear. Has this happened to anyone else? Does anyone have an idea why it may have happened? The shaft turns freely.

[TurboZ24]

Um. The reasons for cam gear failure could be poor lubrication, excessive oil pressures, or material the cam is made from (if it's a billet cam).

[RednBlack]

Distributor shaft isn't oiled in the conventional method, under pressure. Really doesn't need much oil. Probably something under the cap interfered and sheared the pin and the teeth.

Your link didn't work for me. What kind of 3.4 has a distributor?

[TurboZ24]

Well, it isn't pressure lubricated, but one of the oil galleries passes directly through the drive gear "hole". I usually add a slight groove too the end of the distributor drive plug or distributor too add a little additional lubrication. I also run a bronze/aluminum alloy gear since my cam has a billet steel drive gear on it. My cam will eat a stock cast drive gear (and will not even scratch the cam gear).

[OldSkoolGP]

I think he's referrng to the oil pump drive since it used to be a distributor drive as well. But it that sheared while you were driving and your motor died, you have a locked up motor because you had no oil pump. That would be a bad situation.

[Kreb]

I fixed my website link. The engine is a Camaro donor that I've used an old S-10 ignition (with MSD).

Usually there's a lot of oil down there. Once I forgot to tighten the distributor bolt and oil was coming out.

The engine isn't seized up, but I'm not sure if the oil pump is turning. Were that to seize it might take the distributor with it I imagine.

Tonight I'll check the oil pump and check the oil for shavings.

I hope that the 3.4 can handle the stress of track days and auto-x's. I don't want to have to open up the motor every couple of months

[Kreb]

The oil pump shaft is twisted. Looks like something too large to flow got into the gears, starting a chain reaction.

Now I've got to find all the pieces, change the cam and the oil pump.

Oh boy

[gpse3400]

If it makes you feel any better my oil pump drive on my Camaro committed suicide due to the HV oil pump I had installed. The load that pump put on it was great enough to strip the gear.

[RednBlack]

The oil pump shaft is twisted. Looks like something too large to flow got into the gears, starting a chain reaction.

Now I've got to find all the pieces, change the cam and the oil pump.

Oh boy

I would for sure find out what caused the pump to lock up. Valve train, cylinders, something trashed, and it all washes down. Oil pan sump will hold more pieces, probably too large to get through the screen.

Oil Pumps Suck! (Get pics)

BTW, nice car!

[Kreb]

Just wanted to give you an update. I dropped the pan and found chunks 'o metal. Some were cast pieces from the distributor gear, but there were also little pieces of light gauge metal, like a stamped collar of some sort came apart. The other big discovery was that the oil intake tube/strainer had dropped off of the pump, allowing one of those chunks to enter the gears. The pump gears jammed, the shaft pretzeled and the distributor gear sheared.

The engine still turns, so I'm going to pull off some bearing caps and the intake manifold and see what I've got. I'm hoping everything's salvageable, but am afraid that there are still going to be chunks floating around the engine trying to do mischief.

One useful thing that I've taken from this saga is: weld your oil intake onto the pump! It's supposed to be a press fit, but in my case the fit is very loose. In high performance applications this is an obvious weak link. I'd probably still be driving if that tube had stayed attached.