Elysian

No oil pressure.

A few days ago I backed out of the driveway, dumped the clutch and tried to put on a nice show for the neighbors. I definitely left some rubber on the road, but for inscrutable reasons, all the gauges on my dash cluster immediately went dead. My first thought was an electrical problem. I turned the car off and back on. All gauges were working except for oil pressure. I’d happily ignore an SES light, low coolant, etc., but not low oil pressure. So I parked the car. I checked my oil. It was a bit low, but far from empty, and there are no leaks. Not trusting the digital gauge on the dash, I replaced the oil pressure sensor on the back on the intake and installed a mechanical Autometer oil pressure gauge at the same time. There is indeed no oil pressure; not a drop getting to the gauge or the top of the motor.

Right now I suspect a broken oil pump drive, but haven’t confirmed yet. As you might imagine, I’m not excited about pulling the intake just to check. Before I start tearing the motor apart, I was hoping for some advice/suggestions about what others think might be wrong. Thanks,

~Luke~

mrmint69

I have heard the oil pump pick up can come out and cause no oil pressure. The screen at the bottom of the oil pick up tube can become blocked. Does not sound like that would be it, since it happened instantly. I would check the oil pump for sure. Did the engine start to tick, when it happened till you shut it down?

Elysian

Ticking? Nothing out of the ordinary. It has a big cam, so it tends to sound like a sewing machine anyway. In any case, I didn't let it run very long after I lost pressure...

RamAir95TA

It's either pull the intake manifold now or later, unfortunately. Honestly it sounds like a stripped drive gear.

faster01nu

I had the same thing happen. I pulled the intake to find two red shop rags in the valley of the motor!!! they where in there for a long time, disintegrated, and eventually clogged my oil pick up tube! Previouse owner must have had intake gaskets done and left them in there. Only had 87K on the clock when it went!

SSinister11x

My oil pressure gauge seems to read pretty low. After it warms up the needle is between the 2 bottem lines on the stock oil pressure gauge.. is that normal or do I have an issue as well? When I give it gas the pressure will climb up to a little bit above half way mark.

RamAir95TA

If the "check gauges" light isn't on your oil pressure is fine. By your explanation it sounds good to me.

Elysian

Assuming it's a stripped drive gear, is there an after-market replacement better than the stock unit? If so, where, how much, etc.?

RamAir95TA

It really depends on the type of cam/cam gear you have. I have always had good luck with the stock one. Some people prefer to press on a hardened gear. But from my experience there is no "best choice" for everyone.

I've been running my STOCK (17 year old) drive gear with two different cams including my current build with a HV oil pump.

Elysian

Apparently Herron Performance makes a billet aluminum oil pump drive, but they expect you to re-use some of the stock components.

Herron Performance - LT1 Billet Oil Pump Drive

A search online shows a few people replacing the stock drive gear with a bronze one.

Lt1 oil pump drive with new gear - LS1TECH

Any idea where to get this gear?

cnorton

I think I bought a bronze gear from either Comp Cams or Crane Cams. Perhaps the best option would be the "composite" gear from Comp Cams. Before ordering, be sure to verify the diameter of the shaft that goes through the center of the gear. There's more than one size available.

Elysian

Stock gear. Bronze gear. "Composite" gear. For me this is about longevity. This motor is daily driven. Probably has 35K miles on it. Assuming the oil pump drive is the culprit for my oiling woes, I would like to replace the entire unit with something I don't have to think about for the life of the motor (I like permanent solutions). What are the pros/cons of the stock gear? Bronze gear? Composite gear? If it makes any difference, I run a custom Comp cam...

cnorton

The decision is usually based on the material of the camshaft. I used a bronze gear because my camshaft was ground on a steel billet with serious spring pressures (upwards of 700# on the seat). The composite gear is also reported to be compatible with either a regular cam or a steel billet cam. If your cam is ground on a stock core, either a composite gear or a stock gear would work. If you're not sure, call Comp Cams and ask for Chris Padgitt. I've been going to him for ordering advice for almost 20 years. He'll be able to tell you what will work and what won't.

If your breakage is related to the body of the pump drive itself rather than the gear, it's an entirely different issue. I've seen some pump drive housings that have broken due to improper tightening or over-tightening. I've never seen the aluminum drive housing that you referenced in your earlier post but certainly an aluminum housing would be more durable than a stock one. Having said that, I ran a stock drive with a bronze gear on my Super Stock LT1 for dozens of runs in excess of 8000 RPM with no problems. If yours is broken, look for a logical explanation because, if they're installed correctly and torqued to spec, they should last virtually for the life of the car.

I'm still guessing that you'll find the oil pump pickup laying loose in the bottom of the pan.

Elysian

That would be a (relatively) more convenient problem. Anyway. Thanks for the input. Much appreciated.